1
|
Almohaywi M, Sugita BM, Centa A, Fonseca AS, Antunes VC, Fadda P, Mannion CM, Abijo T, Goldberg SL, Campbell MC, Copeland RL, Kanaan Y, Cavalli LR. Deregulated miRNA Expression in Triple-Negative Breast Cancer of Ancestral Genomic-Characterized Latina Patients. Int J Mol Sci 2023; 24:13046. [PMID: 37685851 PMCID: PMC10487916 DOI: 10.3390/ijms241713046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/03/2023] [Accepted: 08/05/2023] [Indexed: 09/10/2023] Open
Abstract
Among patients with triple-negative breast cancer (TNBC), several studies have suggested that deregulated microRNA (miRNA) expression may be associated with a more aggressive phenotype. Although tumor molecular signatures may be race- and/or ethnicity-specific, there is limited information on the molecular profiles in women with TNBC of Hispanic and Latin American ancestry. We simultaneously profiled TNBC biopsies for the genome-wide copy number and miRNA global expression from 28 Latina women and identified a panel of 28 miRNAs associated with copy number alterations (CNAs). Four selected miRNAs (miR-141-3p, miR-150-5p, miR-182-5p, and miR-661) were validated in a subset of tumor and adjacent non-tumor tissue samples, with miR-182-5p being the most discriminatory among tissue groups (AUC value > 0.8). MiR-141-3p up-regulation was associated with increased cancer recurrence; miR-661 down-regulation with larger tumor size; and down-regulation of miR-150-5p with larger tumor size, high p53 expression, increased cancer recurrence, presence of distant metastasis, and deceased status. This study reinforces the importance of integration analysis of CNAs and miRNAs in TNBC, allowing for the identification of interactions among molecular mechanisms. Additionally, this study emphasizes the significance of considering the patients ancestral background when examining TNBC, as it can influence the relationship between intrinsic tumor molecular characteristics and clinical manifestations of the disease.
Collapse
Affiliation(s)
- Maram Almohaywi
- Microbiology Department, Howard University Cancer Center, Howard University, Washington, DC 20059, USA
| | - Bruna M. Sugita
- Research Institute Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba 80250-060, PR, Brazil
| | - Ariana Centa
- Research Institute Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba 80250-060, PR, Brazil
| | - Aline S. Fonseca
- Research Institute Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba 80250-060, PR, Brazil
| | - Valquiria C. Antunes
- Research Institute Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba 80250-060, PR, Brazil
| | - Paolo Fadda
- Genomics Shared Resource, Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA
| | - Ciaran M. Mannion
- Department of Pathology, Hackensack University Medical Center, Hackensack, NJ 07701, USA
| | - Tomilowo Abijo
- National Institute of Diabetes and Kidney Diseases, National Institute of Health, Bethesda, MD 20814, USA
| | - Stuart L. Goldberg
- John Theurer Cancer Center, Hackensack Meridian School of Medicine, Hackensack, NJ 07701, USA
- COTA, Inc., New York, NY 10014, USA
| | - Michael C. Campbell
- Department of Biological Sciences Human and Evolutionary Biology Section, University of Southern California, Los Angeles, CA 90089, USA
| | - Robert L. Copeland
- Pharmacology Department, Howard University Cancer Center, Howard University, Washington, DC 20059, USA
| | - Yasmine Kanaan
- Microbiology Department, Howard University Cancer Center, Howard University, Washington, DC 20059, USA
| | - Luciane R. Cavalli
- Research Institute Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba 80250-060, PR, Brazil
- Oncology Department, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20007, USA
| |
Collapse
|
2
|
Zhang C, Verma A, Feng Y, Melo MCR, McQuillan M, Hansen M, Lucas A, Park J, Ranciaro A, Thompson S, Rubel MA, Campbell MC, Beggs W, Hirbo J, Wata Mpoloka S, George Mokone G, Nyambo T, Wolde Meskel D, Belay G, Fokunang C, Njamnshi AK, Omar SA, Williams SM, Rader DJ, Ritchie MD, de la Fuente-Nunez C, Sirugo G, Tishkoff SA. Impact of natural selection on global patterns of genetic variation and association with clinical phenotypes at genes involved in SARS-CoV-2 infection. Proc Natl Acad Sci U S A 2022; 119:e2123000119. [PMID: 35580180 PMCID: PMC9173769 DOI: 10.1073/pnas.2123000119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 03/29/2022] [Indexed: 01/09/2023] Open
Abstract
Human genomic diversity has been shaped by both ancient and ongoing challenges from viruses. The current coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a devastating impact on population health. However, genetic diversity and evolutionary forces impacting host genes related to SARS-CoV-2 infection are not well understood. We investigated global patterns of genetic variation and signatures of natural selection at host genes relevant to SARS-CoV-2 infection (angiotensin converting enzyme 2 [ACE2], transmembrane protease serine 2 [TMPRSS2], dipeptidyl peptidase 4 [DPP4], and lymphocyte antigen 6 complex locus E [LY6E]). We analyzed data from 2,012 ethnically diverse Africans and 15,977 individuals of European and African ancestry with electronic health records and integrated with global data from the 1000 Genomes Project. At ACE2, we identified 41 nonsynonymous variants that were rare in most populations, several of which impact protein function. However, three nonsynonymous variants (rs138390800, rs147311723, and rs145437639) were common among central African hunter-gatherers from Cameroon (minor allele frequency 0.083 to 0.164) and are on haplotypes that exhibit signatures of positive selection. We identify signatures of selection impacting variation at regulatory regions influencing ACE2 expression in multiple African populations. At TMPRSS2, we identified 13 amino acid changes that are adaptive and specific to the human lineage compared with the chimpanzee genome. Genetic variants that are targets of natural selection are associated with clinical phenotypes common in patients with COVID-19. Our study provides insights into global variation at host genes related to SARS-CoV-2 infection, which have been shaped by natural selection in some populations, possibly due to prior viral infections.
Collapse
Affiliation(s)
- Chao Zhang
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Anurag Verma
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Division of Translational Medicine and Human Genetics, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104
| | - Yuanqing Feng
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Marcelo C. R. Melo
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104
- Penn Institute for Computational Science, University of Pennsylvania, Philadelphia, PA 19104
| | - Michael McQuillan
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Matthew Hansen
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Anastasia Lucas
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Joseph Park
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Alessia Ranciaro
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Simon Thompson
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Meagan A. Rubel
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Michael C. Campbell
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089
| | - William Beggs
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Jibril Hirbo
- Department of Medicine, Vanderbilt University, Nashville, TN 37232
| | | | | | | | - Thomas Nyambo
- Department of Biochemistry, Kampala International University in Tanzania, Dar es Salaam, Tanzania
| | - Dawit Wolde Meskel
- Department of Microbial Cellular and Molecular Biology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Gurja Belay
- Department of Microbial Cellular and Molecular Biology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Charles Fokunang
- Department of Pharmacotoxicology and Pharmacokinetics, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon
| | - Alfred K. Njamnshi
- Department of Neurology, Central Hospital Yaoundé, Yaoundé, Cameroon
- Brain Research Africa Initiative, Neuroscience Laboratory, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon
| | - Sabah A. Omar
- Center for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Scott M. Williams
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH 44106
| | - Daniel J. Rader
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Marylyn D. Ritchie
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Cesar de la Fuente-Nunez
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104
- Penn Institute for Computational Science, University of Pennsylvania, Philadelphia, PA 19104
| | - Giorgio Sirugo
- Division of Translational Medicine and Human Genetics, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104
| | - Sarah A. Tishkoff
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104
- Center for Global Genomics and Health Equity, University of Pennsylvania, Philadelphia, PA 19104
| |
Collapse
|
3
|
Zhang C, Verma A, Feng Y, Melo MCR, McQuillan M, Hansen M, Lucas A, Park J, Ranciaro A, Thompson S, Rubel MA, Campbell MC, Beggs W, Hirbo J, Mpoloka SW, Mokone GG, Nyambo T, Meskel DW, Belay G, Fokunang C, Njamnshi AK, Omar SA, Williams SM, Rader D, Ritchie MD, de la Fuente Nunez C, Sirugo G, Tishkoff S. Impact of natural selection on global patterns of genetic variation, and association with clinical phenotypes, at genes involved in SARS-CoV-2 infection. medRxiv 2021:2021.06.28.21259529. [PMID: 34230933 PMCID: PMC8259910 DOI: 10.1101/2021.06.28.21259529] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
We investigated global patterns of genetic variation and signatures of natural selection at host genes relevant to SARS-CoV-2 infection (ACE2, TMPRSS2, DPP4, and LY6E). We analyzed novel data from 2,012 ethnically diverse Africans and 15,997 individuals of European and African ancestry with electronic health records, and integrated with global data from the 1000GP. At ACE2, we identified 41 non-synonymous variants that were rare in most populations, several of which impact protein function. However, three non-synonymous variants were common among Central African hunter-gatherers from Cameroon and are on haplotypes that exhibit signatures of positive selection. We identify strong signatures of selection impacting variation at regulatory regions influencing ACE2 expression in multiple African populations. At TMPRSS2, we identified 13 amino acid changes that are adaptive and specific to the human lineage. Genetic variants that are targets of natural selection are associated with clinical phenotypes common in patients with COVID-19.
Collapse
Affiliation(s)
- Chao Zhang
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Anurag Verma
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yuanqing Feng
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marcelo C. R. Melo
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, Penn Institute for Computational Science, and Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael McQuillan
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Matthew Hansen
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Anastasia Lucas
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Joseph Park
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alessia Ranciaro
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Simon Thompson
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Meghan A. Rubel
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | - William Beggs
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | | | | | | | | - Thomas Nyambo
- Department of Biochemistry, Kampala International University in Tanzania, Dar es Salaam, Tanzania
| | - Dawit Wolde Meskel
- Addis Ababa University Department of Microbial Cellular and Molecular Biology, Addis Ababa, Ethiopia
| | - Gurja Belay
- Addis Ababa University Department of Microbial Cellular and Molecular Biology, Addis Ababa, Ethiopia
| | - Charles Fokunang
- Department of Pharmacotoxicology and Pharmacokinetics, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon
| | - Alfred K. Njamnshi
- Department of Neurology, Central Hospital Yaoundé; Brain Research Africa Initiative (BRAIN), Neuroscience Lab, Faculty of Medicine and Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon
| | - Sabah A. Omar
- Center for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | | | - Daniel Rader
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marylyn D. Ritchie
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Cesar de la Fuente Nunez
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, Penn Institute for Computational Science, and Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Giorgio Sirugo
- Division of Translational Medicine and Human Genetics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104
| | - Sarah Tishkoff
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|
4
|
Turkistani S, Sugita BM, Fadda P, Marchi R, Afsari A, Naab T, Apprey V, Copeland RL, Campbell MC, Cavalli LR, Kanaan Y. A panel of miRNAs as prognostic markers for African-American patients with triple negative breast cancer. BMC Cancer 2021; 21:861. [PMID: 34315420 PMCID: PMC8317413 DOI: 10.1186/s12885-021-08573-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 04/29/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND To investigate the global expression profile of miRNAs, their impact on cellular signaling pathways, and their association with poor prognostic parameters in African-American (AA) patients with triple negative breast cancer (TNBC). METHODS Twenty-five samples of AA TNBC patients were profiled for global miRNA expression and stratified considering three clinical-pathological parameters: tumor size, lymph node (LN), and recurrence (REC) status. Differential miRNA expression analysis was performed for each parameter, and their discriminatory power was determined by Receiver Operating Characteristic (ROC) curve analysis. KMplotter was assessed to determine the association of the miRNAs with survival, and functional enrichment analysis to determine the main affected pathways and miRNA/mRNA target interactions. RESULTS A panel of eight, 23 and 27 miRNAs were associated with tumor size, LN, and REC status, respectively. Combined ROC analysis of two (miR-2117, and miR-378c), seven (let-7f-5p, miR-1255b-5p, miR-1268b, miR-200c-3p, miR-520d, miR-527, and miR-518a-5p), and three (miR-1200, miR-1249-3p, and miR-1271-3p) miRNAs showed a robust discriminatory power based on tumor size (AUC = 0.917), LN (AUC = 0.945) and REC (AUC = 0.981) status, respectively. Enrichment pathway analysis revealed their involvement in proteoglycans and glycan and cancer-associated pathways. Eight miRNAs with deregulated expressions in patients with large tumor size, positive LN metastasis, and recurrence were significantly associated with lower survival rates. Finally, the construction of miRNA/mRNA networks based in experimentally validated mRNA targets, revealed nodes of critical cancer genes, such as AKT1, BCL2, CDKN1A, EZR and PTEN. CONCLUSIONS Altogether, our data indicate that miRNA deregulated expression is a relevant biological factor that can be associated with the poor prognosis in TNBC of AA patients, by conferring to their TNBC cells aggressive phenotypes that are reflected in the clinical characteristics evaluated in this study.
Collapse
Affiliation(s)
- Safaa Turkistani
- grid.257127.40000 0001 0547 4545Department of Microbiology, Howard University Cancer Center, Howard University, Washington DC, USA
| | - Bruna M. Sugita
- Research Institute Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba, PR Brazil
| | - Paolo Fadda
- grid.261331.40000 0001 2285 7943Genomics Shared Resource, Comprehensive Cancer Center, The Ohio State University, Columbus, OH USA
| | - Rafael Marchi
- Research Institute Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba, PR Brazil
| | - Ali Afsari
- grid.411399.70000 0004 0427 2775Department of Pathology, Howard University Hospital, Washington DC, USA
| | - Tammey Naab
- grid.411399.70000 0004 0427 2775Department of Pathology, Howard University Hospital, Washington DC, USA
| | - Victor Apprey
- grid.257127.40000 0001 0547 4545Department of Community and Family Medicine, Howard University, Washington DC, USA
| | - Robert L. Copeland
- grid.257127.40000 0001 0547 4545Department of Pharmacology, College of Medicine and Cancer Center, Howard University, Washington DC, USA
| | - Michael C. Campbell
- grid.257127.40000 0001 0547 4545Department of Biology, Howard University, Washington DC, USA
| | - Luciane R. Cavalli
- Research Institute Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba, PR Brazil ,grid.213910.80000 0001 1955 1644Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington DC, USA
| | - Yasmine Kanaan
- grid.257127.40000 0001 0547 4545Department of Microbiology, Howard University Cancer Center, Howard University, Washington DC, USA
| |
Collapse
|
5
|
Musa TH, Ahmad T, Wana MN, Li W, Musa HH, Sharun K, Tiwari R, Dhama K, Chaicumpa W, Campbell MC, Wei P. The epidemiology, diagnosis and management of scrub typhus disease in China. Hum Vaccin Immunother 2021; 17:3795-3805. [PMID: 34124995 DOI: 10.1080/21645515.2021.1934355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Thirty-nine years ago, scrub typhus (ST), a disease, was not among the China's notifiable diseases. However, ST has reemerged to become a growing public health issue in the southwest part of China. The major factors contributing to an increased incidence and prevalence of this disease include rapid globalization, urbanization, expansion of humans into previously uninhabited areas, and climate change. The clinical manifestation of ST also consists of high fever, headache, weakness, myalgia, rash, and an eschar. In severe cases, complications (e.g. multi-organ failure, jaundice, acute renal failure, pneumonitis, myocarditis, and even death) can occur. The diagnosis of ST is mainly based on serological identification by indirect immunofluorescence assay and other molecular methods. Furthermore, several groups of antibiotics (e.g. tetracycline, chloramphenicol, macrolides, and rifampicin) are currently effective in treating this disease. This fact suggests the need for robust early diagnostic techniques, increased surveillance, and prompt treatment, and develop future vaccine.
Collapse
Affiliation(s)
- Taha Hussein Musa
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing, China.,Biomedical Research Institute (BRI), Darfur College, Nyala, Sudan
| | - Tauseef Ahmad
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing, China
| | - Mohammed Nasiru Wana
- Department of Biological Sciences, Faculty of Science, Abubakar Tafawa Balewa University, Bauchi, Nigeria
| | - Wei Li
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing, China
| | - Hassan Hussein Musa
- Faculty of Medical Laboratory Sciences, University of Khartoum, Khartoum, Sudan
| | - Khan Sharun
- Division of Surgery, ICAR-Indian Veterinary Research Institute, Bareilly, India
| | - Ruchi Tiwari
- Department of Veterinary Microbiology and Immunology, College of Veterinary Sciences, UP Deen Dayal Upadhayaya Pashu Chikitsa Vigyan Vishwavidyalay Evum Go-Anusandhan Sansthan (DUVASU), Mathura, India
| | - Kuldeep Dhama
- Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly, India
| | - Wanpen Chaicumpa
- Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | | | - Pingmin Wei
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing, China
| |
Collapse
|
6
|
Campbell MC, Ranciaro A. Human adaptation, demography and cattle domestication: an overview of the complexity of lactase persistence in Africa. Hum Mol Genet 2021; 30:R98-R109. [PMID: 33847744 DOI: 10.1093/hmg/ddab027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/13/2021] [Accepted: 01/13/2021] [Indexed: 01/30/2023] Open
Abstract
Lactase persistence (LP) is a genetically-determined trait that is prevalent in African, European and Arab populations with a tradition of animal herding and milk consumption. To date, genetic analyses have identified several common variants that are associated with LP. Furthermore, data have indicated that these functional alleles likely have been maintained in pastoralist populations due to the action of recent selection, exemplifying the ongoing evolution of anatomically modern humans. Additionally, demographic history has also played a role in the geographic distribution of LP and associated alleles in Africa. In particular, the migration of ancestral herders and their subsequent admixture with local populations were integral to the spread of LP alleles and the culture of pastoralism across the continent. The timing of these demographic events was often correlated with known major environmental changes and/or the ability of domesticated cattle to resist/avoid infectious diseases. This review summarizes recent advances in our understanding of the genetic basis and evolutionary history of LP, as well as the factors that influenced the origin and spread of pastoralism in Africa.
Collapse
Affiliation(s)
- Michael C Campbell
- Department of Biology, Howard University, EE Just Hall Biology Building, 415 College Street NW, Washington, DC 20059, USA
| | - Alessia Ranciaro
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, 415 Curie Boulevard, Philadelphia, PA 19104, USA
| |
Collapse
|
7
|
Musa HH, Musa TH, Musa IH, Musa IH, Ranciaro A, Campbell MC. Addressing Africa's pandemic puzzle: Perspectives on COVID-19 transmission and mortality in sub-Saharan Africa. Int J Infect Dis 2021; 102:483-488. [PMID: 33010461 PMCID: PMC7526606 DOI: 10.1016/j.ijid.2020.09.1456] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 09/21/2020] [Indexed: 12/12/2022] Open
Abstract
To date, SARS-CoV-2 (the virus that causes COVID-19) has spread to almost every region of the world, infecting millions and resulting in the deaths of hundreds of thousands of people. Although it was predicted that Africa would suffer a massive loss of life due to this pandemic, the number of COVID-19 cases has been relatively low across the continent. Researchers have speculated that several factors may be responsible for this outcome in Africa, including the extensive experience that countries have with infectious diseases and the young median age of their populations. However, it is still important for African countries to adopt aggressive and bold approaches against COVID-19, in case the nature of the pandemic changes. This short review will summarize the status of the outbreak in Africa and propose possible reasons for current trends, as well as discuss interventions aimed at preventing a rapid increase in the number of COVID-19 cases in the future.
Collapse
Affiliation(s)
- Hassan H Musa
- Biomedical Research Institute, Darfur College, Nyala, Sudan; Faculty of Medical Laboratory Sciences, University of Khartoum, Sudan
| | - Taha H Musa
- Biomedical Research Institute, Darfur College, Nyala, Sudan; School of Medicine, Darfur College, Nyala, Sudan
| | | | - Ibrahim H Musa
- Biomedical Research Institute, Darfur College, Nyala, Sudan
| | - Alessia Ranciaro
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | |
Collapse
|
8
|
Eastwood PR, Barnes M, MacKay SG, Wheatley JR, Lewis R, Campbell MC, Jones AC, Palme CE, Petelle B, Meslier N, Bertolus C, Denoncin K, Attali V, Gagnadoux F, Launois SH. 0665 Bilateral Hypoglossal Nerve Stimulation for Treatment of Obstructive Sleep Apnea. Sleep 2020. [DOI: 10.1093/sleep/zsaa056.661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
Hypoglossal Nerve Stimulation (HGNS) decreases obstructive sleep apnea (OSA) severity by contracting the tongue and decreasing upper airway collapsibility. This study assessed the safety and effectiveness of a new implantable device that delivers bilateral HGNS: the Genio™ system.
Methods
The BLAST OSA study (BiLAteral Hypoglossal Nerve Stimulation for Treatment of Obstructive Sleep Apnea), was a prospective, open-label, non-randomized, single arm treatment study conducted at eight centres in three countries (Australia, France, UK). Primary outcomes were the incidence of device-related Serious Adverse Events (SAEs) and change in the Apnea-Hypopnea Index (AHI). The secondary outcome was change in the 4% Oxygen Desaturation Index (ODI). Additional outcomes included measures of sleepiness, quality of life, snoring, and device use. Participants were eligible if: 21-75 years old; BMI ≤ 32 kg/m2; obstructive AHI 20-60 events/hr and combined central and mixed AHI < 10 events/hr; no positional OSA; no Complete Concentric Collapse of the soft palate during Drug Induced Sleep Endoscopy; and failed to tolerate or accept Positive Airway Pressure treatments.
Results
27 participants were implanted (63% male, aged 55.9±12.0 years, BMI 27.4±3.0 kg/m2). 22 completed the protocol. At 6 months, AHI decreased from 23.7±12.2 to 12.9±10.1 events/hr [p<0.001]; and ODI decreased from 19.1±11.2 to 9.8±6.9 events/hr [p<0.001]. Daytime sleepiness (ESS, p=0.011) and sleep-related quality of life (FOSQ-10, p=0.016) both significantly improved. 91% of participants reported using their device >5 days per week, and 77% used it >5 hours per night. The number of bed partners reporting disruptive snoring decreased from 96% to 35%. No device-related SAE occurred.
Conclusion
In a targeted population of individuals with moderate-to-severe OSA, the Genio system reduced OSA severity and sleepiness, improved quality of life, and was associated with high adherence and an acceptable safety profile.
Support
This study trial was funded by Nyxoah S.A. This trial was registered with ClinicalTrials.gov, number NCT03048604.
Collapse
Affiliation(s)
- P R Eastwood
- University of Western Australia, Centre for Sleep Science, Perth, AUSTRALIA
| | - M Barnes
- Institute for Breathing and Sleep, Austin Hospital, Melbourne, AUSTRALIA
| | - S G MacKay
- Illawara ENT Head & Neck Clinic, Woollongong, AUSTRALIA
| | - J R Wheatley
- Depatment of Respiratory and Sleep Medicine, Westmead Hospital, Sydney, AUSTRALIA
| | - R Lewis
- Department of Otolaryngology, Head & Neck Surgery, Royal Perth Hosptital, Perth, AUSTRALIA
| | - M C Campbell
- Institute for Breathing and Sleep, Austin Hospital, Melbourne, AUSTRALIA
| | - A C Jones
- Illawarra ENG Head & Neck Clinic, Woollongong, AUSTRALIA
| | - C E Palme
- University of Sydney at Westmead Hospital, Sydney, AUSTRALIA
| | - B Petelle
- Service ORL Chirurgie de la Face et du Cou, Hopital Tenon, Paris, FRANCE
| | - N Meslier
- Department of Respiratory and Sleep Medicine, University Hospital of Angers, Angers, FRANCE
| | - C Bertolus
- AP-HP, Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Paris, FRANCE
| | - K Denoncin
- Nyxoah, S.A., Mont-Saint-Guibert, BELGIUM
| | - V Attali
- Sorbonne Universite, INSERM, UMRS 1158, Neurophysiologie Respiratoire Experimentale et Clinique, Paris, FRANCE
| | - F Gagnadoux
- Department of Respiratory and Sleep Medicine, University of Angers, Angers, FRANCE
| | - S H Launois
- Unite de Somnologie et Fonction Respiratoire, Hospital St Antoine, Paris, FRANCE
| |
Collapse
|
9
|
Campbell MC, Ashong B, Teng S, Harvey J, Cross CN. Correction to: Multiple selective sweeps of ancient polymorphisms in and around LTα located in the MHC class III region on chromosome 6. BMC Evol Biol 2019; 19:225. [PMID: 31842744 PMCID: PMC6912931 DOI: 10.1186/s12862-019-1557-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
After publication of our article [1] we were notified that a few duplicate sentences were included on Figure 3 and Figure 4 legends.
Collapse
Affiliation(s)
- Michael C. Campbell
- 0000 0001 0547 4545grid.257127.4Department of Biology, College of Arts and Sciences, Howard University, Washington, DC, 20059 USA
| | - Bryan Ashong
- 0000 0001 0547 4545grid.257127.4Department of Biology, College of Arts and Sciences, Howard University, Washington, DC, 20059 USA
| | - Shaolei Teng
- 0000 0001 0547 4545grid.257127.4Department of Biology, College of Arts and Sciences, Howard University, Washington, DC, 20059 USA
| | - Jayla Harvey
- 0000 0001 0547 4545grid.257127.4Department of Biology, College of Arts and Sciences, Howard University, Washington, DC, 20059 USA
| | - Christopher N. Cross
- 0000 0001 0547 4545grid.257127.4Department of Anatomy, College of Medicine, Howard University, Washington, DC, 20059 USA
| |
Collapse
|
10
|
Campbell MC. Recurrent Use of Implantable Buprenorphine. Prim Care Companion CNS Disord 2019; 21. [DOI: 10.4088/pcc.19l02434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
|
11
|
Campbell MC, Ashong B, Teng S, Harvey J, Cross CN. Multiple selective sweeps of ancient polymorphisms in and around LTα located in the MHC class III region on chromosome 6. BMC Evol Biol 2019; 19:218. [PMID: 31791241 PMCID: PMC6889576 DOI: 10.1186/s12862-019-1516-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 09/20/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Lymphotoxin-α (LTα), located in the Major Histocompatibility Complex (MHC) class III region on chromosome 6, encodes a cytotoxic protein that mediates a variety of antiviral responses among other biological functions. Furthermore, several genotypes at this gene have been implicated in the onset of a number of complex diseases, including myocardial infarction, autoimmunity, and various types of cancer. However, little is known about levels of nucleotide variation and linkage disequilibrium (LD) in and near LTα, which could also influence phenotypic variance. To address this gap in knowledge, we examined sequence variation across ~ 10 kilobases (kbs), encompassing LTα and the upstream region, in 2039 individuals from the 1000 Genomes Project originating from 21 global populations. RESULTS Here, we observed striking patterns of diversity, including an excess of intermediate-frequency alleles, the maintenance of multiple common haplotypes and a deep coalescence time for variation (dating > 1.0 million years ago), in global populations. While these results are generally consistent with a model of balancing selection, we also uncovered a signature of positive selection in the form of long-range LD on chromosomes with derived alleles primarily in Eurasian populations. To reconcile these findings, which appear to support different models of selection, we argue that selective sweeps (particularly, soft sweeps) of multiple derived alleles in and/or near LTα occurred in non-Africans after their ancestors left Africa. Furthermore, these targets of selection were predicted to alter transcription factor binding site affinity and protein stability, suggesting they play a role in gene function. Additionally, our data also showed that a subset of these functional adaptive variants are present in archaic hominin genomes. CONCLUSIONS Overall, this study identified candidate functional alleles in a biologically-relevant genomic region, and offers new insights into the evolutionary origins of these loci in modern human populations.
Collapse
Affiliation(s)
- Michael C. Campbell
- Department of Biology, College of Arts and Sciences, Howard University, Washington, DC 20059 USA
| | - Bryan Ashong
- Department of Biology, College of Arts and Sciences, Howard University, Washington, DC 20059 USA
| | - Shaolei Teng
- Department of Biology, College of Arts and Sciences, Howard University, Washington, DC 20059 USA
| | - Jayla Harvey
- Department of Biology, College of Arts and Sciences, Howard University, Washington, DC 20059 USA
| | - Christopher N. Cross
- Department of Anatomy, College of Medicine, Howard University, Washington, DC 20059 USA
| |
Collapse
|
12
|
Hansen MEB, Rubel MA, Bailey AG, Ranciaro A, Thompson SR, Campbell MC, Beggs W, Dave JR, Mokone GG, Mpoloka SW, Nyambo T, Abnet C, Chanock SJ, Bushman FD, Tishkoff SA. Population structure of human gut bacteria in a diverse cohort from rural Tanzania and Botswana. Genome Biol 2019; 20:16. [PMID: 30665461 PMCID: PMC6341659 DOI: 10.1186/s13059-018-1616-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 12/20/2018] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Gut microbiota from individuals in rural, non-industrialized societies differ from those in individuals from industrialized societies. Here, we use 16S rRNA sequencing to survey the gut bacteria of seven non-industrialized populations from Tanzania and Botswana. These include populations practicing traditional hunter-gatherer, pastoralist, and agropastoralist subsistence lifestyles and a comparative urban cohort from the greater Philadelphia region. RESULTS We find that bacterial diversity per individual and within-population phylogenetic dissimilarity differs between Botswanan and Tanzanian populations, with Tanzania generally having higher diversity per individual and lower dissimilarity between individuals. Among subsistence groups, the gut bacteria of hunter-gatherers are phylogenetically distinct from both agropastoralists and pastoralists, but that of agropastoralists and pastoralists were not significantly different from each other. Nearly half of the Bantu-speaking agropastoralists from Botswana have gut bacteria that are very similar to the Philadelphian cohort. Based on imputed metagenomic content, US samples have a relative enrichment of genes found in pathways for degradation of several common industrial pollutants. Within two African populations, we find evidence that bacterial composition correlates with the genetic relatedness between individuals. CONCLUSIONS Across the cohort, similarity in bacterial presence/absence compositions between people increases with both geographic proximity and genetic relatedness, while abundance weighted bacterial composition varies more significantly with geographic proximity than with genetic relatedness.
Collapse
Affiliation(s)
- Matthew E B Hansen
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Meagan A Rubel
- Department of Anthropology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Aubrey G Bailey
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Present address: Kuopio Center for Gene and Cell Therapy, Microkatu 1, 70210, Kuopio, Finland
| | - Alessia Ranciaro
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Simon R Thompson
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Present address: Genomics England, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Michael C Campbell
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Present address: Department of Biology, Howard University, 415 College St. NW, Washington, DC, USA
| | - William Beggs
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Jaanki R Dave
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- The Geisinger Commonwealth Medical College, Scranton, PA, 18509, USA
| | - Gaonyadiwe G Mokone
- Department of Biomedical Sciences, University of Botswana School of Medicine, Gaborone, Botswana
| | | | - Thomas Nyambo
- Department of Biochemistry, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Christian Abnet
- Cancer Genomics Research Laboratory, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Stephen J Chanock
- Cancer Genomics Research Laboratory, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Frederic D Bushman
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Sarah A Tishkoff
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| |
Collapse
|
13
|
Zhao ZM, Campbell MC, Li N, Lee DSW, Zhang Z, Townsend JP. Detection of Regional Variation in Selection Intensity within Protein-Coding Genes Using DNA Sequence Polymorphism and Divergence. Mol Biol Evol 2018; 34:3006-3022. [PMID: 28962009 DOI: 10.1093/molbev/msx213] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Numerous approaches have been developed to infer natural selection based on the comparison of polymorphism within species and divergence between species. These methods are especially powerful for the detection of uniform selection operating across a gene. However, empirical analyses have demonstrated that regions of protein-coding genes exhibiting clusters of amino acid substitutions are subject to different levels of selection relative to other regions of the same gene. To quantify this heterogeneity of selection within coding sequences, we developed Model Averaged Site Selection via Poisson Random Field (MASS-PRF). MASS-PRF identifies an ensemble of intragenic clustering models for polymorphic and divergent sites. This ensemble of models is used within the Poisson Random Field framework to estimate selection intensity on a site-by-site basis. Using simulations, we demonstrate that MASS-PRF has high power to detect clusters of amino acid variants in small genic regions, can reliably estimate the probability of a variant occurring at each nucleotide site in sequence data and is robust to historical demographic trends and recombination. We applied MASS-PRF to human gene polymorphism derived from the 1,000 Genomes Project and divergence data from the common chimpanzee. On the basis of this analysis, we discovered striking regional variation in selection intensity, indicative of positive or negative selection, in well-defined domains of genes that have previously been associated with neurological processing, immunity, and reproduction. We suggest that amino acid-altering substitutions within these regions likely are or have been selectively advantageous in the human lineage, playing important roles in protein function.
Collapse
Affiliation(s)
- Zi-Ming Zhao
- Department of Biostatistics, Yale University, New Haven, CT
| | - Michael C Campbell
- Department of Biostatistics, Yale University, New Haven, CT.,Department of Biology, Howard University, Washington, DC
| | - Ning Li
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT
| | - Daniel S W Lee
- Department of Biostatistics, Yale University, New Haven, CT
| | - Zhang Zhang
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Jeffrey P Townsend
- Department of Biostatistics, Yale University, New Haven, CT.,Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT.,Program in Computational Biology and Bioinformatics, Yale University, New Haven, CT
| |
Collapse
|
14
|
Crawford NG, Kelly DE, Hansen MEB, Beltrame MH, Fan S, Bowman SL, Jewett E, Ranciaro A, Thompson S, Lo Y, Pfeifer SP, Jensen JD, Campbell MC, Beggs W, Hormozdiari F, Mpoloka SW, Mokone GG, Nyambo T, Meskel DW, Belay G, Haut J, Rothschild H, Zon L, Zhou Y, Kovacs MA, Xu M, Zhang T, Bishop K, Sinclair J, Rivas C, Elliot E, Choi J, Li SA, Hicks B, Burgess S, Abnet C, Watkins-Chow DE, Oceana E, Song YS, Eskin E, Brown KM, Marks MS, Loftus SK, Pavan WJ, Yeager M, Chanock S, Tishkoff SA. Loci associated with skin pigmentation identified in African populations. Science 2017; 358:eaan8433. [PMID: 29025994 PMCID: PMC5759959 DOI: 10.1126/science.aan8433] [Citation(s) in RCA: 191] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Accepted: 10/03/2017] [Indexed: 12/13/2022]
Abstract
Despite the wide range of skin pigmentation in humans, little is known about its genetic basis in global populations. Examining ethnically diverse African genomes, we identify variants in or near SLC24A5, MFSD12, DDB1, TMEM138, OCA2, and HERC2 that are significantly associated with skin pigmentation. Genetic evidence indicates that the light pigmentation variant at SLC24A5 was introduced into East Africa by gene flow from non-Africans. At all other loci, variants associated with dark pigmentation in Africans are identical by descent in South Asian and Australo-Melanesian populations. Functional analyses indicate that MFSD12 encodes a lysosomal protein that affects melanogenesis in zebrafish and mice, and that mutations in melanocyte-specific regulatory regions near DDB1/TMEM138 correlate with expression of ultraviolet response genes under selection in Eurasians.
Collapse
Affiliation(s)
- Nicholas G Crawford
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Derek E Kelly
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Genomics and Computational Biology Graduate Program, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Matthew E B Hansen
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marcia H Beltrame
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Shaohua Fan
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Shanna L Bowman
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, PA 19104, USA
- Department of Pathology and Laboratory Medicine and Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ethan Jewett
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA 94704, USA
- Department of Statistics, University of California, Berkeley, Berkeley, CA 94704, USA
| | - Alessia Ranciaro
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Simon Thompson
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yancy Lo
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Susanne P Pfeifer
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Jeffrey D Jensen
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Michael C Campbell
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Biology, Howard University, Washington, DC 20059, USA
| | - William Beggs
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Farhad Hormozdiari
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | | | - Gaonyadiwe George Mokone
- Department of Biomedical Sciences, University of Botswana School of Medicine, Gaborone, Botswana
| | - Thomas Nyambo
- Department of Biochemistry, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | | | - Gurja Belay
- Department of Biology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Jake Haut
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Harriet Rothschild
- Stem Cell Program, Division of Hematology and Oncology, Pediatric Hematology Program, Boston Children's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Leonard Zon
- Stem Cell Program, Division of Hematology and Oncology, Pediatric Hematology Program, Boston Children's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
- Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Yi Zhou
- Stem Cell Program, Division of Hematology and Oncology, Pediatric Hematology Program, Boston Children's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
- Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Michael A Kovacs
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mai Xu
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tongwu Zhang
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kevin Bishop
- Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jason Sinclair
- Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Cecilia Rivas
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Eugene Elliot
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jiyeon Choi
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shengchao A Li
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20892, USA
- Frederick National Laboratory for Cancer Research, Leidos Biomedical Research Inc., Frederick, MD 21701, USA
| | - Belynda Hicks
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20892, USA
- Frederick National Laboratory for Cancer Research, Leidos Biomedical Research Inc., Frederick, MD 21701, USA
| | - Shawn Burgess
- Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Christian Abnet
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20892, USA
| | - Dawn E Watkins-Chow
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Elena Oceana
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Yun S Song
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA 94704, USA
- Department of Statistics, University of California, Berkeley, Berkeley, CA 94704, USA
- Chan Zuckerberg Biohub, San Francisco, CA 94158, USA
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Mathematics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Eleazar Eskin
- Department of Computer Science and Department of Human Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Kevin M Brown
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Michael S Marks
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, PA 19104, USA
- Department of Pathology and Laboratory Medicine and Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Stacie K Loftus
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - William J Pavan
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Meredith Yeager
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20892, USA
- Frederick National Laboratory for Cancer Research, Leidos Biomedical Research Inc., Frederick, MD 21701, USA
| | - Stephen Chanock
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20892, USA
| | - Sarah A Tishkoff
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|
15
|
Campbell MC, Hirbo JB, Townsend JP, Tishkoff SA. The peopling of the African continent and the diaspora into the new world. Curr Opin Genet Dev 2015; 29:120-32. [PMID: 25461616 DOI: 10.1016/j.gde.2014.09.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 09/03/2014] [Accepted: 09/05/2014] [Indexed: 12/22/2022]
Abstract
Africa is the birthplace of anatomically modern humans, and is the geographic origin of human migration across the globe within the last 100,000 years. The history of African populations has consisted of a number of demographic events that have influenced patterns of genetic and phenotypic variation across the continent. With the increasing amount of genomic data and corresponding developments in computational methods, researchers are able to explore long-standing evolutionary questions, expanding our understanding of human history within and outside of Africa. This review will summarize some of the recent findings regarding African demographic history, including the African Diaspora, and will briefly explore their implications for disease susceptibility in populations of African descent.
Collapse
|
16
|
Rawlings-Goss RA, Campbell MC, Tishkoff SA. Global population-specific variation in miRNA associated with cancer risk and clinical biomarkers. BMC Med Genomics 2014; 7:53. [PMID: 25169894 PMCID: PMC4159108 DOI: 10.1186/1755-8794-7-53] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 08/12/2014] [Indexed: 12/30/2022] Open
Abstract
Background MiRNA expression profiling is being actively investigated as a clinical biomarker and diagnostic tool to detect multiple cancer types and stages as well as other complex diseases. Initial investigations, however, have not comprehensively taken into account genetic variability affecting miRNA expression and/or function in populations of different ethnic backgrounds. Therefore, more complete surveys of miRNA genetic variability are needed to assess global patterns of miRNA variation within and between diverse human populations and their effect on clinically relevant miRNA genes. Methods Genetic variation in 1524 miRNA genes was examined using whole genome sequencing (60x coverage) in a panel of 69 unrelated individuals from 14 global populations, including European, Asian and African populations. Results We identified 33 previously undescribed miRNA variants, and 31 miRNA containing variants that are globally population-differentiated in frequency between African and non-African populations (PD-miRNA). The top 1% of PD-miRNA were significantly enriched for regulation of genes involved in glucose/insulin metabolism and cell division (p < 10−7), most significantly the mitosis pathway, which is strongly linked to cancer onset. Overall, we identify 7 PD-miRNAs that are currently implicated as cancer biomarkers or diagnostics: hsa-mir-202, hsa-mir-423, hsa-mir-196a-2, hsa-mir-520h, hsa-mir-647, hsa-mir-943, and hsa-mir-1908. Notably, hsa-mir-202, a potential breast cancer biomarker, was found to show significantly high allele frequency differentiation at SNP rs12355840, which is known to affect miRNA expression levels in vivo and subsequently breast cancer mortality. Conclusion MiRNA expression profiles represent a promising new category of disease biomarkers. However, population specific genetic variation can affect the prevalence and baseline expression of these miRNAs in diverse populations. Consequently, miRNA genetic and expression level variation among ethnic groups may be contributing in part to health disparities observed in multiple forms of cancer, specifically breast cancer, and will be an essential consideration when assessing the utility of miRNA biomarkers for the clinic.
Collapse
|
17
|
Campbell MC, Ranciaro A, Zinshteyn D, Rawlings-Goss R, Hirbo J, Thompson S, Woldemeskel D, Froment A, Omar SA, Bodo JM, Nyambo T, Belay G, Drayna D, Breslin PAS, Tishkoff SA. Limited evidence for adaptive evolution and functional effect of allelic variation at rs702424 in the promoter of the TAS2R16 bitter taste receptor gene in Africa. J Hum Genet 2014; 59:349-52. [PMID: 24785689 PMCID: PMC4075171 DOI: 10.1038/jhg.2014.29] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/03/2014] [Accepted: 04/07/2014] [Indexed: 11/09/2022]
Abstract
Bitter taste perception, mediated by receptors encoded by the TAS2R loci, has important roles in human health and nutrition. Prior studies have demonstrated that nonsynonymous variation at site 516 in the coding exon of TAS2R16, a bitter taste receptor gene on chromosome 7, has been subject to positive selection and is strongly correlated with differences in sensitivity to salicin, a bitter anti-inflammatory compound, in human populations. However, a recent study suggested that the derived G-allele at rs702424 in the TAS2R16 promoter has also been the target of recent selection and may have an additional effect on the levels of salicin bitter taste perception. Here, we examined alleles at rs702424 for signatures of selection using Extended Haplotype Homozygosity (EHH) and FST statistics in diverse populations from West Central, Central and East Africa. We also performed a genotype-phenotype analysis of salicin sensitivity in a subset of 135 individuals from East Africa. Based on our data, we did not find evidence for positive selection at rs702424 in African populations, suggesting that nucleotide position 516 is likely the site under selection at TAS2R16. Moreover, we did not detect a significant association between rs702424 alleles and salicin bitter taste recognition, implying that this site does not contribute to salicin phenotypic variance. Overall, this study of African diversity provides further information regarding the genetic architecture and evolutionary history of a biologically-relevant trait in humans.
Collapse
Affiliation(s)
- Michael C Campbell
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Alessia Ranciaro
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Daniel Zinshteyn
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Jibril Hirbo
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Simon Thompson
- Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA
| | - Dawit Woldemeskel
- 1] Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA [2] Biology Department, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - Sabah A Omar
- Kenya Medical Research Institute, Centre for Biotechnology Research and Development, Nairobi, Kenya
| | - Jean-Marie Bodo
- Ministry of Scientific Research and Innovation, Yaounde, Cameroon
| | - Thomas Nyambo
- Department of Biochemistry, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Gurja Belay
- Biology Department, Addis Ababa University, Addis Ababa, Ethiopia
| | - Dennis Drayna
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Rockville, MD, USA
| | - Paul A S Breslin
- 1] Monell Chemical Senses Center, Philadelphia, PA, USA [2] Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Sarah A Tishkoff
- 1] Department of Genetics, University of Pennsylvania, Philadelphia, PA, USA [2] Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
18
|
Ranciaro A, Campbell MC, Hirbo JB, Ko WY, Froment A, Anagnostou P, Kotze MJ, Ibrahim M, Nyambo T, Omar SA, Tishkoff SA. Genetic origins of lactase persistence and the spread of pastoralism in Africa. Am J Hum Genet 2014; 94:496-510. [PMID: 24630847 PMCID: PMC3980415 DOI: 10.1016/j.ajhg.2014.02.009] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2013] [Accepted: 02/14/2014] [Indexed: 10/25/2022] Open
Abstract
In humans, the ability to digest lactose, the sugar in milk, declines after weaning because of decreasing levels of the enzyme lactase-phlorizin hydrolase, encoded by LCT. However, some individuals maintain high enzyme amounts and are able to digest lactose into adulthood (i.e., they have the lactase-persistence [LP] trait). It is thought that selection has played a major role in maintaining this genetically determined phenotypic trait in different human populations that practice pastoralism. To identify variants associated with the LP trait and to study its evolutionary history in Africa, we sequenced MCM6 introns 9 and 13 and ~2 kb of the LCT promoter region in 819 individuals from 63 African populations and in 154 non-Africans from nine populations. We also genotyped four microsatellites in an ~198 kb region in a subset of 252 individuals to reconstruct the origin and spread of LP-associated variants in Africa. Additionally, we examined the association between LP and genetic variability at candidate regulatory regions in 513 individuals from eastern Africa. Our analyses confirmed the association between the LP trait and three common variants in intron 13 (C-14010, G-13907, and G-13915). Furthermore, we identified two additional LP-associated SNPs in intron 13 and the promoter region (G-12962 and T-956, respectively). Using neutrality tests based on the allele frequency spectrum and long-range linkage disequilibrium, we detected strong signatures of recent positive selection in eastern African populations and the Fulani from central Africa. In addition, haplotype analysis supported an eastern African origin of the C-14010 LP-associated mutation in southern Africa.
Collapse
Affiliation(s)
- Alessia Ranciaro
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Michael C Campbell
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jibril B Hirbo
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Wen-Ya Ko
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alain Froment
- UMR 208, Musée de l'Homme, Muséum National d'Histoire Naturelle and Institut de Recherche pour le Développement, 75116 Paris, France
| | - Paolo Anagnostou
- Dipartimento di Biologia Ambientale, Università La Sapienza, 00185 Rome, Italy; Istituto Italiano di Antropologia, 00100 Rome, Italy
| | - Maritha J Kotze
- Division of Anatomical Pathology, Department of Pathology, Faculty of Health Sciences, University of Stellenbosch, Tygerberg 7505, South Africa
| | - Muntaser Ibrahim
- Department of Molecular Biology, Institute of Endemic Diseases, University of Khartoum, 15-13 Khartoum, Sudan
| | - Thomas Nyambo
- Department of Biochemistry, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Sabah A Omar
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, 54840-00200 Nairobi, Kenya
| | - Sarah A Tishkoff
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
19
|
Campbell MC, Ranciaro A, Zinshteyn D, Rawlings-Goss R, Hirbo J, Thompson S, Woldemeskel D, Froment A, Rucker JB, Omar SA, Bodo JM, Nyambo T, Belay G, Drayna D, Breslin PAS, Tishkoff SA. Origin and differential selection of allelic variation at TAS2R16 associated with salicin bitter taste sensitivity in Africa. Mol Biol Evol 2013; 31:288-302. [PMID: 24177185 DOI: 10.1093/molbev/mst211] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Bitter taste perception influences human nutrition and health, and the genetic variation underlying this trait may play a role in disease susceptibility. To better understand the genetic architecture and patterns of phenotypic variability of bitter taste perception, we sequenced a 996 bp region, encompassing the coding exon of TAS2R16, a bitter taste receptor gene, in 595 individuals from 74 African populations and in 94 non-Africans from 11 populations. We also performed genotype-phenotype association analyses of threshold levels of sensitivity to salicin, a bitter anti-inflammatory compound, in 296 individuals from Central and East Africa. In addition, we characterized TAS2R16 mutants in vitro to investigate the effects of polymorphic loci identified at this locus on receptor function. Here, we report striking signatures of positive selection, including significant Fay and Wu's H statistics predominantly in East Africa, indicating strong local adaptation and greater genetic structure among African populations than expected under neutrality. Furthermore, we observed a "star-like" phylogeny for haplotypes with the derived allele at polymorphic site 516 associated with increased bitter taste perception that is consistent with a model of selection for "high-sensitivity" variation. In contrast, haplotypes carrying the "low-sensitivity" ancestral allele at site 516 showed evidence of strong purifying selection. We also demonstrated, for the first time, the functional effect of nonsynonymous variation at site 516 on salicin phenotypic variance in vivo in diverse Africans and showed that most other nonsynonymous substitutions have weak or no effect on cell surface expression in vitro, suggesting that one main polymorphism at TAS2R16 influences salicin recognition. Additionally, we detected geographic differences in levels of bitter taste perception in Africa not previously reported and infer an East African origin for high salicin sensitivity in human populations.
Collapse
|
20
|
Hill KK, Campbell MC, McNeely ME, Karimi M, Ushe M, Tabbal SD, Hershey T, Flores HP, Hartlein JM, Lugar HM, Revilla FJ, Videen TO, Earhart GM, Perlmutter JS. Cerebral blood flow responses to dorsal and ventral STN DBS correlate with gait and balance responses in Parkinson's disease. Exp Neurol 2013; 241:105-12. [PMID: 23262122 PMCID: PMC3570746 DOI: 10.1016/j.expneurol.2012.12.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 12/03/2012] [Accepted: 12/06/2012] [Indexed: 01/04/2023]
Abstract
OBJECTIVES The effects of subthalamic nucleus (STN) deep brain stimulation (DBS) on gait and balance vary and the underlying mechanisms remain unclear. DBS location may alter motor benefit due to anatomical heterogeneity in STN. The purposes of this study were to (1) compare the effects of DBS of dorsal (D-STN) versus ventral (V-STN) regions on gait, balance and regional cerebral blood flow (rCBF) and (2) examine the relationships between changes in rCBF and changes in gait and balance induced by D-STN or V-STN DBS. METHODS We used a validated atlas registration to locate and stimulate through electrode contacts in D-STN and V-STN regions of 37 people with Parkinson's disease. In a within-subjects, double-blind and counterbalanced design controlled for DBS settings, we measured PET rCBF responses in a priori regions of interest and quantified gait and balance during DBS Off, unilateral D-STN DBS and unilateral V-STN DBS. RESULTS DBS of either site increased stride length without producing significant group-level changes in gait velocity, cadence or balance. Both sites increased rCBF in subcortical regions and produced variable changes in cortical and cerebellar regions. DBS-induced changes in gait velocity are related to premotor cortex rCBF changes during V-STN DBS (r=-0.40, p=0.03) and to rCBF changes in the cerebellum anterior lobe during D-STN DBS (r=-0.43, p=0.02). CONCLUSIONS DBS-induced changes in gait corresponded to rCBF responses in selected cortical and cerebellar regions. These relationships differed during D-STN versus V-STN DBS, suggesting DBS acts through distinct neuronal pathways dependent on DBS location.
Collapse
Affiliation(s)
- K K Hill
- Department of Biomedical Engineering, Washington University School of Medicine, St. Louis, MO, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Brown CA, Campbell MC, Karimi M, Tabbal SD, Loftin SK, Tian LL, Moerlein SM, Perlmutter JS. Dopamine pathway loss in nucleus accumbens and ventral tegmental area predicts apathetic behavior in MPTP-lesioned monkeys. Exp Neurol 2012; 236:190-7. [PMID: 22579525 PMCID: PMC3367030 DOI: 10.1016/j.expneurol.2012.04.025] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 04/10/2012] [Accepted: 04/23/2012] [Indexed: 01/29/2023]
Abstract
Apathy, primarily defined as a lack of motivation, commonly occurs in people with Parkinson disease (PD). Although dysfunction of basal ganglia pathways may contribute to apathy, the role of dopamine remains largely unknown. We investigated the role of dopaminergic pathways in the manifestation of apathetic behaviors by measuring the effects of the selective dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on monkeys' willingness to attempt goal directed behaviors, distinct from their ability to perform tasks. Fifteen macaques received variable doses of MPTP, had PET scans with [(11)C]-dihydrotetrabenazine (DTBZ), [(11)C]-2β-3β-4-fluorophenyltropane (CFT), and [(18)F]-fluorodopa (FD) and performed tasks to assess apathetic behaviors and motor impairment. At 8 weeks post-MPTP, primates were euthanized and stereological cell counts and dopamine measurements were done. Apathy scores were compared to motor scores, in vitro and in vivo dopaminergic measures. Apathy scores increased following MPTP and correlated with DTBZ (r(S) = -0.85), CFT (r(S) = -0.87), and FD (r(S) = -0.85) specific uptake in nucleus accumbens (NAcc,) and dopaminergic cell counts in ventral tegmental area (VTA, r(S) = -0.80). Dopaminergic cell loss in VTA provided significant predictive power for apathy scores after controlling for the influence of cell loss in SN. Additionally, forward step-wise regression analyses indicated that neuropathological changes in the VTA-NAcc pathway predict apathetic behavior better than motor impairment or neuropathological changes in the nigrostriatal network. Our findings suggest that dopaminergic dysfunction within the VTA-NAcc pathway plays a role in the manifestation of apathetic behaviors in MPTP-lesioned primates. Similar changes in people with PD may contribute to apathy.
Collapse
Affiliation(s)
- C A Brown
- Neurology, Washington University School of Medicine, St Louis, MO 63110, USA
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Campbell MC, Ranciaro A, Froment A, Hirbo J, Omar S, Bodo JM, Nyambo T, Lema G, Zinshteyn D, Drayna D, Breslin PAS, Tishkoff SA. Evolution of functionally diverse alleles associated with PTC bitter taste sensitivity in Africa. Mol Biol Evol 2011; 29:1141-53. [PMID: 22130969 DOI: 10.1093/molbev/msr293] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Although human bitter taste perception is hypothesized to be a dietary adaptation, little is known about genetic signatures of selection and patterns of bitter taste perception variability in ethnically diverse populations with different diets, particularly from Africa. To better understand the genetic basis and evolutionary history of bitter taste sensitivity, we sequenced a 2,975 bp region encompassing TAS2R38, a bitter taste receptor gene, in 611 Africans from 57 populations in West Central and East Africa with diverse subsistence patterns, as well as in a comparative sample of 132 non-Africans. We also examined the association between genetic variability at this locus and threshold levels of phenylthiocarbamide (PTC) bitterness in 463 Africans from the above populations to determine how variation influences bitter taste perception. Here, we report striking patterns of variation at TAS2R38, including a significant excess of novel rare nonsynonymous polymorphisms that recently arose only in Africa, high frequencies of haplotypes in Africa associated with intermediate bitter taste sensitivity, a remarkably similar frequency of common haplotypes across genetically and culturally distinct Africans, and an ancient coalescence time of common variation in global populations. Additionally, several of the rare nonsynonymous substitutions significantly modified levels of PTC bitter taste sensitivity in diverse Africans. While ancient balancing selection likely maintained common haplotype variation across global populations, we suggest that recent selection pressures may have also resulted in the unusually high level of rare nonsynonymous variants in Africa, implying a complex model of selection at the TAS2R38 locus in African populations. Furthermore, the distribution of common haplotypes in Africa is not correlated with diet, raising the possibility that common variation may be under selection due to their role in nondietary biological processes. In addition, our data indicate that novel rare mutations contribute to the phenotypic variance of PTC sensitivity, illustrating the influence of rare variation on a common trait, as well as the relatively recent evolution of functionally diverse alleles at this locus.
Collapse
|
23
|
McNeely ME, Hershey T, Campbell MC, Tabbal SD, Karimi M, Hartlein JM, Lugar HM, Revilla FJ, Perlmutter JS, Earhart GM. Effects of deep brain stimulation of dorsal versus ventral subthalamic nucleus regions on gait and balance in Parkinson's disease. J Neurol Neurosurg Psychiatry 2011; 82:1250-5. [PMID: 21478202 PMCID: PMC3250990 DOI: 10.1136/jnnp.2010.232900] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves motor function, including gait and stability, in people with Parkinson's disease (PD) but differences in DBS contact locations within the STN may contribute to variability in the degree of improvement. Based on anatomical connectivity, dorsal STN may be preferentially involved in motor function and ventral STN in cognitive function. METHODS To determine whether dorsal DBS affects gait and balance more than ventral DBS, a double blind evaluation of 23 PD patients with bilateral STN DBS was conducted. Each participant underwent gait analysis and balance testing off Parkinson's medication under three DBS conditions (unilateral DBS in the dorsal STN region, unilateral DBS in the ventral STN region and both stimulators off) on 1 day. RESULTS Improvements were seen in Unified Parkinson's Disease Rating Scale (UPDRS)-III scores and velocity in walking trials as fast as possible (Fast gait) and preferred pace (Pref gait), as well as stride length for Fast and Pref gait, with dorsal and ventral stimulation compared with the off condition (post hoc tests, p<0.05). However, there were no differences with dorsal compared to ventral stimulation. Balance, assessed using the multi-item mini-Balance Evaluation Systems Test (mini-BESTest), was similar across conditions. CONCLUSIONS Absence of differences in gait and balance between the dorsal and ventral conditions suggests motor connections involved in gait and balance may be more diffusely distributed in STN than previously thought, as opposed to neural connections involved in cognitive processes, such as response inhibition, which are more affected by ventral stimulation.
Collapse
Affiliation(s)
- M E McNeely
- Program in Physical Therapy, Washington University School of Medicine, St Louis, MO 63108, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Campbell MC. Hyponatremia and central pontine myelinolysis as a result of beer potomania: a case report. Prim Care Companion J Clin Psychiatry 2010; 12. [PMID: 21085565 DOI: 10.4088/pcc.09l00936ecr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
25
|
Abstract
Africa is the birthplace of modern humans, and is the source of the geographic expansion of ancestral populations into other regions of the world. Indigenous Africans are characterized by high levels of genetic diversity within and between populations. The pattern of genetic variation in these populations has been shaped by demographic events occurring over the last 200,000 years. The dramatic variation in climate, diet, and exposure to infectious disease across the continent has also resulted in novel genetic and phenotypic adaptations in extant Africans. This review summarizes some recent advances in our understanding of the demographic history and selective pressures that have influenced levels and patterns of diversity in African populations.
Collapse
Affiliation(s)
- Michael C Campbell
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | | |
Collapse
|
26
|
Campbell MC, Tishkoff SA. African genetic diversity: implications for human demographic history, modern human origins, and complex disease mapping. Annu Rev Genomics Hum Genet 2008; 9:403-33. [PMID: 18593304 DOI: 10.1146/annurev.genom.9.081307.164258] [Citation(s) in RCA: 503] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Comparative studies of ethnically diverse human populations, particularly in Africa, are important for reconstructing human evolutionary history and for understanding the genetic basis of phenotypic adaptation and complex disease. African populations are characterized by greater levels of genetic diversity, extensive population substructure, and less linkage disequilibrium (LD) among loci compared to non-African populations. Africans also possess a number of genetic adaptations that have evolved in response to diverse climates and diets, as well as exposure to infectious disease. This review summarizes patterns and the evolutionary origins of genetic diversity present in African populations, as well as their implications for the mapping of complex traits, including disease susceptibility.
Collapse
Affiliation(s)
- Michael C Campbell
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19107, USA.
| | | |
Collapse
|
27
|
Campbell MC, Karimi M, Weaver PM, Wu J, Perantie DC, Golchin NA, Tabbal SD, Perlmutter JS, Hershey T. Neural correlates of STN DBS-induced cognitive variability in Parkinson disease. Neuropsychologia 2008; 46:3162-9. [PMID: 18682259 DOI: 10.1016/j.neuropsychologia.2008.07.012] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Revised: 05/21/2008] [Accepted: 07/14/2008] [Indexed: 11/16/2022]
Abstract
BACKGROUND Although deep brain stimulation of the subthalamic nucleus (STN DBS) in Parkinson disease (PD) improves motor function, it has variable effects on working memory (WM) and response inhibition (RI) performance. The purpose of this study was to determine the neural correlates of STN DBS-induced variability in cognitive performance. METHODS We measured bilateral STN DBS-induced blood flow changes (PET and [(15)O]-water on one day) in the supplementary motor area (SMA), dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex (ACC), and right inferior frontal cortex (rIFC) as well as in exploratory ROIs defined by published meta-analyses. STN DBS-induced WM and RI changes (Spatial Delayed Response and Go-No-Go on the next day) were measured in 24 PD participants. On both days, participants withheld PD medications overnight and conditions (OFF vs. ON) were administered in a counterbalanced, double-blind manner. RESULTS As predicted, STN DBS-induced DLPFC blood flow change correlated with change in WM, but not RI performance. Furthermore, ACC blood flow change correlated with change in RI but not WM performance. For both relationships, increased blood flow related to decreased cognitive performance in response to STN DBS. Of the exploratory regions, only blood flow changes in DLPFC and ACC were correlated with performance. CONCLUSIONS These results demonstrate that variability in the effects of STN DBS on cognitive performance relates to STN DBS-induced cortical blood flow changes in DLPFC and ACC. This relationship highlights the need to further understand the factors that mediate the variability in neural and cognitive response to STN DBS.
Collapse
Affiliation(s)
- M C Campbell
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, United States
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Abstract
We investigated whether the development of the vertebrate crystalline lens is sensitive to visual input. The optical properties of fish lenses were examined as a function of lens size and the optical rearing conditions. Fish (Haplochromis burtoni, Cichlidae) were reared in white light (control group), under spectral deprivation (monochromatic lights), deprivation of the cone system (scotopic illumination), and complete visual deprivation (darkness). Longitudinal spherical aberrations (LSAs) and refractive index profiles of the lenses were measured with thin laser beams. The performance of the lens was modeled by ray-tracing calculations from measured LSAs. In lenses from the control group, LSA and f/R (focal length relative to lens radius) decreased as a function of age. The optical properties of the lenses were modified after rearing in darkness, scotopic illumination, and in monochromatic lights due to changes in the refractive index profile. Rearing in darkness and scotopic illumination reduced the optical quality of the lens. In animals reared under spectral deprivation, the lens did not create well-focused images for all spectral cone types in the same plane, as it does in animals reared in white light. We conclude that visual input seems to play an important role in the development of the lens. The control mechanisms remain unknown.
Collapse
Affiliation(s)
- R H Kröger
- Institute of Neuroscience, University of Oregon, Eugene, OR 97403, USA.
| | | | | |
Collapse
|
29
|
Abstract
The biometric, optical and physical properties of 19 pairs of isolated human eye-bank lenses ranging in age from 5 to 96 years were compared. Lens focal length and spherical aberration were measured using a scanning laser apparatus, lens thickness and the lens surface curvatures were measured by digitizing the lens profiles and equivalent refractive indices were calculated for each lens using this data. The second lens from each donor was used to measure resistance to physical deformation by providing a compressive force to the lens. The lens capsule was then removed from each lens and each measurement was repeated to ascertain what role the capsule plays in determining these optical and physical characteristics. Age dependent changes in lens focal length, lens surface curvatures and lens resistance to physical deformation are described. Isolated lens focal length was found to be significantly linearly correlated with both the anterior and posterior surface curvatures. No age dependent change in equivalent refractive index of the isolated lens was found. Although decapsulating human lenses causes similar changes in focal length to that which we have shown to occur when human lenses are mechanically stretched into an unaccommodated state, the effects are due to nonsystematic changes in lens curvatures. These studies reinforce the conclusion that lens hardening must be considered as an important factor in the development of presbyopia, that age changes in the human lens are not limited to the loss of accommodation that characterizes presbyopia but that the lens optical and physical properties change substantially with age in a complex manner.
Collapse
Affiliation(s)
- A Glasser
- College of Optometry, University of Houston, TX 77204, USA.
| | | |
Collapse
|
30
|
Kröger RH, Campbell MC, Fernald RD, Wagner HJ. Multifocal lenses compensate for chromatic defocus in vertebrate eyes. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 1999; 184:361-9. [PMID: 10377973 DOI: 10.1007/s003590050335] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The focal length of the vertebrate eye is a function of wavelength, i.e. the eye suffers from longitudinal chromatic aberration. Chromatic defocus is a particularly severe problem in eyes with high light-gathering ability, since depth of field is small due to a pupillary opening that is large in relation to the focal length of the eye. Calculations show that in such eyes only a narrow spectral band of light can be in focus on the retina. For the major part of the visual spectrum, spatial resolution should be limited by the optics of the eye and far lower than the resolving power achievable by the retinal cone photoreceptor mosaic. To solve this problem, fishes with irises unresponsive to light have developed lenses with multiple focal lengths. Well-focused images are created at the wavelengths of maximum absorbance of all spectral cone types. Multifocal lenses also appear to be present in some terrestrial species. In eyes with mobile irises, multifocal lenses are correlated with pupil shapes that allow all zones of the lens, with different refractive powers, to participate in the imaging process, irrespective of the state of pupil constriction.
Collapse
Affiliation(s)
- R H Kröger
- Anatomisches Institut, Eberhard-Karls-Universität Tübingen, Germany.
| | | | | | | |
Collapse
|
31
|
Abstract
An objective infrared optometer has been designed, based on the optical principles of eccentric photorefraction. A CCD camera with an eccentric infrared light source images the subject's pupil through a Badal optometer. The slope of the light distribution across the pupil is continuously recorded. Accommodative state is measured by moving the camera behind the Badal lens until the slope is zero. This position corresponds to the case where the camera is conjugate with the retina of the observer. In this Badal optometer, the irradiance of light at the pupil plane, the sensitivity of the photorefractor, and the focal setting of the camera lens remain constant for all positions of the camera from the eye. The repeatability of a single measure of refractive state in a cyclopleged eye was less than 0.05 D. Static accommodative responses taken from 3 subjects in both closed and open loop conditions provided expected stimulus/response measures. The instrument can also be adapted to measure dynamic accommodation.
Collapse
Affiliation(s)
- A Roorda
- School of Optometry, University of Waterloo, Ontario, Canada.
| | | | | |
Collapse
|
32
|
Abstract
Lenses from 27 human eyes ranging in age from 10 to 87 years were used to determine how accommodation and age affect the optical properties of the lens. A scanning laser technique was used to measure focal length and spherical aberration of the lenses, while the lenses were subjected to stretching forces applied through the ciliary body/zonular complex. The focal length of all unstretched lenses increased linearly with increasing age. Younger lenses were able to undergo significant changes in focal length with stretching, whereas lenses older than 60 years of age showed no changes in focal length with stretching. These data provide additional evidence for predominantly lens-based theories of presbyopia. Further, these results show that there are substantial optical changes in the human lens with increasing age and during accommodation, since both the magnitude and the sign of the spherical aberration change with age and stretching. These results show that the optical properties of the older presbyopic lens are quite different from the younger, accommodated lens.
Collapse
Affiliation(s)
- A Glasser
- School of Optometry, University of Waterloo, Ontario, Canada.
| | | |
Collapse
|
33
|
Campbell MC. Rounding the managed care bend. Provider 1997; 23:63-4. [PMID: 10173659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Affiliation(s)
- M C Campbell
- Karrington Advisory Services, Willoughby Hills, OH, USA
| |
Collapse
|
34
|
Roorda A, Campbell MC, Bobier WR. Slope-based eccentric photorefraction: theoretical analysis of different light source configurations and effects of ocular aberrations. J Opt Soc Am A Opt Image Sci Vis 1997; 14:2547-2556. [PMID: 9316272 DOI: 10.1364/josaa.14.002547] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A geometrical-optical technique is used to predict the changes in the slope of the eccentric-photorefraction intensity profiles as a function of refractive state. We investigate how the intensity profiles vary with refractive state for different light source configurations and monochromatic aberrations in the eye. The best possible light source configuration extends from zero eccentricity (to increase sensitivity and reduce the dead zone) to a high eccentricity (to increase the working range). An advantage of using the extended light source is that the intensity profile of the eccentric-photorefraction reflex is more linear for extended sources than for point light sources. It is also shown that the change in slope with refractive state is dependent on pupil size. Furthermore, when asymmetric aberrations are present, the change in intensity profile slope with refractive state is dependent on the circumferential position of the light source, but this dependence can be resolved by averaging slope values obtained by using two sources placed on opposite sides of the pupil. The importance of this study to existing eccentric-photorefractor designs is discussed, and recommendations for improved eccentric photorefractors are suggested.
Collapse
Affiliation(s)
- A Roorda
- School of Optometry, University of Waterloo, Ontario, Canada.
| | | | | |
Collapse
|
35
|
Abstract
Photorefractive methods have become popular in the measurement of refractive and accommodative states of infants and children owing to their photographic nature and rapid speed of measurement. As in the case of any method that measures the refractive state of the human eye, monochromatic aberrations will reduce the accuracy of the measurement. Monochromatic aberrations cannot be as easily predicted or controlled as chromatic aberrations during the measurement, and accordingly they will introduce measurement errors. This study defines the error or uncertainty by extending the existing paraxial optical analyses of coaxial and eccentric photorefraction. This new optical analysis predicts that, for the amounts of spherical aberration (SA) reported for the human eye, there will be a significant degree of measurement uncertainty introduced for all photorefractive methods. The dioptric amount of this uncertainty may exceed the maximum amount of SA present in the eye. The calculated effects on photorefractive measurement of a real eye with a mixture of spherical aberration and coma are shown to be significant. The ability, developed here, to predict photorefractive patterns corresponding to different amounts and types of monochromatic aberration may in the future lead to an extension of photorefractive methods to the dual measurement of refractive states and aberrations of individual eyes.
Collapse
Affiliation(s)
- M C Campbell
- School of Optometry, University of Waterloo, Ontario, Canada
| | | | | |
Collapse
|
36
|
Roorda A, Campbell MC, Bobier WR. Geometrical theory to predict eccentric photorefraction intensity profiles in the human eye. J Opt Soc Am A Opt Image Sci Vis 1995; 12:1647-1656. [PMID: 7674062 DOI: 10.1364/josaa.12.001647] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
In eccentric photorefraction, light returning from the retina of the eye is photographed by a camera focused on the eye's pupil. We use a geometrical model of eccentric photorefraction to generate intensity profiles across the pupil image. The intensity profiles for three different monochromatic aberration functions induced in a single eye are predicted and show good agreement with the measured eccentric photorefraction intensity profiles. A directional reflection from the retina is incorporated into the calculation. Intensity profiles for symmetric and asymmetric aberrations are generated and measured. The latter profile shows a dependency on the source position and the meridian. The magnitude of the effect of thresholding on measured pattern extents is predicted. Monochromatic aberrations in human eyes will cause deviations in the eccentric photorefraction measurements from traditional crescents caused by defocus and may cause misdiagnoses of ametropia or anisometropia. Our results suggest that measuring refraction along the vertical meridian is preferred for screening studies with the eccentric photorefractor.
Collapse
Affiliation(s)
- A Roorda
- School of Optometry, University of Waterloo, Ontario, Canada
| | | | | |
Collapse
|
37
|
Abstract
Lens focal properties (spherical aberration), diameter and relative anterior/posterior proportions were measured photographically for Japanese squid (Sepioteuthis lessoniana) at ages 4-6 weeks, 7-9 weeks and 7-8 months. The measures involved photographing the refractive effects of lenses in a physiological solution, with and without an index matching fluid (polyvinylpyrroloidone solution), on a parallel array of fine helium-neon laser beams. Spherical aberration was determined from measurement of back vertex distance. Similar measurements were made on lenses from the eyes of cuttlefish (Sepia officinalis). The cephalopod lens develops as hemispheric halves from separate ectodermal sources. The posterior component contributes, on average, about 60% of axial lens diameter in S. lessoniana of all ages and 55% in S. officinalis. However, these proportions vary widely in both species. All lenses of both species show that spherical aberration is neutralized, although small variations in back vertex distance (positive and negative spherical aberration) were measured. Preliminary measures indicate that the refractive index distribution within the cephalopod lens varies in a manner reminiscent of teleost lenses. Squid lenses from animals 7-9 weeks of age were optimally corrected for spherical aberration. Some squid of this age, from a separate tank, showed a high incidence of cataract development. In each case, lens opacification was caused by deterioration of the posterior lens component.
Collapse
Affiliation(s)
- J G Sivak
- School of Optometry, University of Waterloo, Ontario, Canada
| | | | | |
Collapse
|
38
|
Kröger RH, Campbell MC, Munger R, Fernald RD. Refractive index distribution and spherical aberration in the crystalline lens of the African cichlid fish Haplochromis burtoni. Vision Res 1994; 34:1815-22. [PMID: 7941384 DOI: 10.1016/0042-6989(94)90306-9] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Refractive index distribution in the teleost crystalline lens was measured with a nondestructive method in freshly excised lenses of the African teleost fish Haplochromis burtoni. Independently, spherical aberration was measured in a parallel set of lenses. The measured refractive index profiles show a continual decrease of refractive index from the center to the surface of the lens. The H. burtoni lens is of high optical quality and slightly overcorrected for spherical aberration. Details of the small residual spherical aberration were accurately predicted by ray-tracing model calculations based on the measured refractive index profile. The refractive index profile and the spherical aberration both show more complex characteristics than suggested by earlier measurements and lens models.
Collapse
Affiliation(s)
- R H Kröger
- Institute of Neuroscience, University of Oregon, Eugene 97403
| | | | | | | |
Collapse
|
39
|
Li Y, Valaitis AP, Latshaw SP, Kwiatkowska D, Tripathi RL, Campbell MC, Kemp RG. Structure and expression of the cDNA for the C isozyme of phosphofructo-1-kinase from rabbit brain. J Biol Chem 1994; 269:5781-7. [PMID: 8119919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Rabbit brain contains three phosphofructo-1-kinase (PFK) isozymic subunits designated A, B, and C. The primary structures of the first of these two isozyme types have been determined previously. The isozyme C of rabbit brain was isolated by immunoaffinity chromatography and subjected to proteolytic and chemical digestion. A large number of peptides were sequenced, the total number of amino acids identified being equal to about 80% of the total structure. The sequence of the cDNA derived from brain mRNA for C isozyme was determined from polymerase chain reaction fragments synthesized using oligonucleotides designed on the basis of the peptide sequences. The deduced size of the C isozyme was 86,371 Da, slightly larger than PFKs described previously. The amino acid sequence identity with the rabbit A isozyme was 68.9% and a range of identity to other sequenced mammalian PFKs was 67-69%. Using these data plus previously published data on chemical modification, assignments of the 6 organic ligand binding sites of PFK were inferred. The full-length cDNA was cloned into and expressed in Escherichia coli. Phosphofructokinase C was purified to homogeneity from the bacterial extracts.
Collapse
Affiliation(s)
- Y Li
- Department of Biological Chemistry, University of Health Sciences, Chicago Medical School, Illinois 60064
| | | | | | | | | | | | | |
Collapse
|
40
|
Bobier WR, Campbell MC, McCreary CR, Power AM, Yang KC. Coaxial photorefractive methods: an optical analysis. Appl Opt 1992; 31:3601-3615. [PMID: 20725331 DOI: 10.1364/ao.31.003601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We provide a novel geometrical optical analysis of two coaxial photorefractive methods (isotropic and orthogonal). The size of the photorefractive pattern is defined in terms of the critical optical parameters without reference to specific camera parameters. A set of equations is derived that defines the following: a working range where the photorefractive pattern increases linearly with refractive error and pupil size, a dead zone where changes in refractive error do not influence pattern size, and critical values where vignetting by the camera lens becomes important. From this analysis optical parameters can be systematically adjusted to vary a photorefractor's working range. Small discrepancies found between measurements taken with model eyes indicated threshold and blooming effects that require calibration.
Collapse
|
41
|
Abstract
Previous measurements of static accommodation have consistently shown steady state errors over most of the range; the response lags below the stimulus and, at low levels, the response leads the stimulus. A series of experiments is presented in which the longitudinal and, for the first time, transverse chromatic aberrations of the eye were varied and the resultant stimulus-response functions of accommodation were measured. The results show that the steady state error of accommodation is not influenced by manipulations of the magnitude or the direction of either longitudinal or transverse chromatic aberration. This indicates that a particular wavelength is not preferentially focussed on the retina as a function of stimulus level and supports the negative feedback theory of accommodation.
Collapse
Affiliation(s)
- W R Bobier
- School of Optometry, University of Waterloo, Ontario, Canada
| | | | | |
Collapse
|
42
|
Abstract
Photorefractive methods allow rapid measures of the refractive and accommodative state of infants and young children whose brief attention and co-operation limit the use of more traditional methods such as retinoscopy and autorefraction. Three methods have been defined: orthogonal, isotropic and eccentric. We provide a common geometrical optical analysis for these three methods where the photorefractive pattern is defined at the plane of focus of the camera. Since this plane is conjugate with the detector plane of the camera then the critical optical parameters can be defined without reference to the design of the camera by simply determining the relative magnification of the projected image of an object photographed at the camera's plane of focus. Specifically the pattern width CF (mm) over a photorefractor's working range can be defined for the isotropic and orthogonal methods as: [formula: see text] and for the eccentric method as: [formula: see text] where: K is a myopic refractive error of the eye (dioptres) (K Less than 0); P the distance of the flash source to the eye (dioptres); L the distance in front of the eye of the camera's plane of focus (dioptres) (L less than 0); GH the pupil diameter (mm); e the eccentricity of the flash source from the camera aperture (mm); M magnification of the image measured relative to the camera plane of focus.
Collapse
Affiliation(s)
- W R Bobier
- University of Waterloo, School of Optometry, Ontario, Canada
| | | | | | | | | |
Collapse
|
43
|
Boyazoglu PA, Palmer C, Campbell MC, Mankgeli MR. The effect of a progesterone/estradiol ear implant on the performance of young beef steers. J S Afr Vet Assoc 1992; 63:23-6. [PMID: 1569536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A progesterone/estradiol ear implant was tested over a 84 d feedlot period on 96 young Bonsmara steers which were randomly allocated to implant and control groups. Animals were adapted over 5 d to a complete feed formulated to South African feedlot standards. Health aberrations were observed and feed intake, mass gain and slaughter data were recorded. The implant group elicited a 23.2 kg gain per animal (P less than 0.01). Mean treatment feed intakes varied marginally but the implant group showed a 14.91% feed to gain improvement over controls. Warm carcass dressing percentage showed an overall improvement of 4.96% for both groups. Bloat incidence was calculated at 0.98% over 8,064 cattle feedlot days. Mortality was 2.08% and 12 animals were considered to be chronic bloaters. This may have been due to the high proportion of fine particles in the diet. A composite feed sample revealed that 62.48% consisted of particle lengths of 0.5-4mm. The effect of this on ruminal health is briefly discussed. It is concluded that the progesterone/estradiol implant provided greater mass gain and improved feed to gain ratios for treated steers over a control group.
Collapse
Affiliation(s)
- P A Boyazoglu
- Faculty of Veterinary Science, Medical University of Southern Africa, Medunsa
| | | | | | | |
Collapse
|
44
|
Wilson MA, Campbell MC, Simonet P. The Julius F. Neumueller Award in Optics, 1989: change of pupil centration with change of illumination and pupil size. Optom Vis Sci 1992; 69:129-36. [PMID: 1584551 DOI: 10.1097/00006324-199202000-00006] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Pupil centration is important to the optical blur on the retina. Using a dual Maxwellian view system we measured the centration of the pupil with respect to the achromatic axis of the eye as a function of pupil size. Significant shifts of the pupil center (up to 0.6 mm) with pupil dilation were measured in both nasal and temporal directions. The effect was usually symmetrical between the two eyes and the shift was linear with pupil size in one-half of the subjects. From their initial positions the linear pupil center shifts with dilation were in the direction of the achromatic axis.
Collapse
Affiliation(s)
- M A Wilson
- School of Optometry, University of Waterloo, Ontario
| | | | | |
Collapse
|
45
|
Simonet P, Campbell MC. Effect of illuminance on the directions of chromostereopsis and transverse chromatic aberration observed with natural pupils. Ophthalmic Physiol Opt 1990; 10:271-9. [PMID: 2216476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The direction of chromostereopsis observed with a natural pupil and the direction of the monocularly perceived disparity between coloured targets (F and C lines - 486 and 656 nm) have been measured in a sample of 30 subjects at 10 and 1000 lx. At both illumination levels approximately equal numbers of subjects perceived positive and negative chromostereopsis. When the ambient illumination was increased, a reversal in the direction of the chromostereopsis occurred for 16 subjects. For six of them a change from a positive to a negative chromostereopsis was observed, a pattern not reported in previous studies. In most cases at both high and low illuminance, there was an absence of perception of a monocular disparity (transverse chromatic aberration), although chromostereopsis was reported, indicating that binocular information can be obtained from sub-threshold monocular disparities. At low illuminance, the lack of correlation between the direction of chromostereopsis and transverse chromatic aberration (TCA) may indicate that there may be a supplementary binocular factor in chromostereopsis.
Collapse
Affiliation(s)
- P Simonet
- School of Optometry, University of Waterloo, Ontario, Canada
| | | |
Collapse
|
46
|
Campbell MC, Simonet P. Video monitoring of the principal ray of a Maxwellian view for the measurement of optical aberrations, the Stiles-Crawford effect, retinal resolution, and for investigating color vision. Appl Opt 1990; 29:1420-1426. [PMID: 20563021 DOI: 10.1364/ao.29.001420] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A video frame grabbing technique with a computer-generated overlay is used to obtain a direct visualization of the position of the image of a point source, producing a Maxwellian view, in the natural entrance pupil of the human eye. With this simple technique, the image point can be located with an accuracy of at least 0.07 mm. Applications are demonstrated: (a) in instruments using a single Maxwellian view for measuring retinal resolution in white light or superimposed Maxwellian views for color vision experiments, (b) in a dual Maxwellian view apparatus used for measuring the Stiles-Crawford effect of the first kind or for measuring chromatic aberration, and (c) in a new semi-Maxwellian view apparatus for the evaluation of monochromatic and chromatic aberrations.
Collapse
|
47
|
Abstract
The horizontal component of optical transverse chromatic aberration (TCA) at the fovea between 486 and 656 nm is measured in a sample of 8 eyes by two novel methods, both using vernier adjustment tasks with a retinal illumination of approx. 780 td and for a pupil size of approximately 5.5 mm dia. Initially, in an indirect method, TCA is derived along the line of sight from chromatic parallax. Secondly, TCA is measured directly using a semi-Maxwellian view and compensating for longitudinal chromatic aberration (LCA). Both techniques are unaffected by coma or by the Stiles-Crawford effects, thus optical TCA rather than the TCA perceived in normal view is measured. On average, optical TCA is in the same direction but less than previously predicted by eye models and predictions of the optical quality of the eye in white light are modified. Factors underlying the lower average value of optical TCA and variability among subjects, especially pupil centration and foveal position, are discussed. The relationship of optical TCA to TCA perceived in normal view and to chromostereopsis is analysed. The results suggest that the optical design of the human eye is optimized to reduce the wavelength dependent phase shift in the optical transfer function, which could be produced by optical TCA.
Collapse
Affiliation(s)
- P Simonet
- School of Optometry, University of Waterloo, Ontario, Canada
| | | |
Collapse
|
48
|
Abstract
The blur on the retina in the horizontal meridian due to monochromatic and chromatic aberrations has been measured using a novel psychophysical technique. Longitudinal chromatic aberration gives the dominant blur for pupil sizes of 4-5 mm, followed by monochromatic aberrations, and blur due to optical transverse chromatic aberration. In some eyes, coma was present as a result of a displacement of the axis of symmetry from the centre of the pupil, but in three eyes, coma was present without spherical aberration. The technique also allows a measurement of the effective pupil centre relative to the geometric centre and a partial analysis of the relative positions of the reference axes of the eye.
Collapse
Affiliation(s)
- M C Campbell
- School of Optometry, University of Waterloo, Ontario, Canada
| | | | | |
Collapse
|
49
|
Sivak JG, Ryall LA, Weerheim J, Campbell MC. Optical constancy of the chick lens during pre- and post-hatching ocular development. Invest Ophthalmol Vis Sci 1989; 30:967-74. [PMID: 2722451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Embryonic and post-embryonic development of the ocular lens is associated with the continual production of new secondary lens fibers by the mitotic activity of equatorial epithelial cells. This continual development affects lens size and shape and refractive index distribution. Study of embryonic lens optical function has been largely ignored. The optical characteristics of the developing chick lens, including paraxial and eccentric focal lengths, were measured during the embryonic period of development and up to 15 days after hatching. Measurements were made with an automated scanning laser system in which the video image of a helium-neon laser beam refracted by an excised lens in solution is digitized. Focal length is measured for beams moving in small steps on either side of that center. Measurements were made on excised lenses as well as with the lens in situ within the anterior segment of the eye. The results, collected from a study of a total of 80 lenses, indicates that embryo lenses at 6-7 days of incubation have long and very variable focal lengths. At the tenth embryo day, focal length drops by more than one-half and focal variations, between lenses and for different beam positions within a single lens, is reduced. Further measures for 14- and 17-day embryo lenses, as well as for lenses from hatchling and 5-, 10- and 15-day-old chicks, indicate that there is little change in focal length, either paraxially or for eccentric beam positions.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- J G Sivak
- School of Optometry, University of Waterloo, Ontario, Canada
| | | | | | | |
Collapse
|
50
|
Abstract
A 25-year-old female presented with severely constricted visual fields secondary to stroke associated with mitral valve prolapse. Repeatably measured central fields of less than 4 degrees diameter showed an unexpected enlargement up to 20 to 40 degrees diameter, when fitted with reversed full field 1.3x and 1.7x Galilean telescopes. Although initial tests indicated no psychogenic component, fields of approximately 20 degrees diameter were eventually obtained through an imitation telescope made with 2 plano lenses. This technique may be useful in determining whether there is a psychogenic component to inexplicable field results in other patients.
Collapse
Affiliation(s)
- M C Campbell
- School of Optometry, University of Waterloo, Ontario, Canada
| | | | | | | |
Collapse
|