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Lee E, Orton K. Cystic fibrosis carrier screening in Australia: comparing sequencing and targeted panels across diverse ancestries. J Med Genet 2025; 62:219-226. [PMID: 39740802 DOI: 10.1136/jmg-2024-110365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2024] [Accepted: 12/10/2024] [Indexed: 01/02/2025]
Abstract
BACKGROUND Targeted cystic fibrosis (CF) carrier screening panels may lack sensitivity in non-European ancestry groups. This study aims to evaluate the sensitivity of various panels in Australian CF carriers identified through sequencing. METHODS The following panels were evaluated in 869 CF carriers: Asuragen, Elucigene, Devyser, American College of Medical Genetics and Genomics and Victorian Clinical Genetics Services. Ancestry-specific CF carrier frequencies from population databases and Bayesian analysis were used to estimate post-test residual carrier risks. RESULTS When variants with varying clinical consequences (VCC) were not considered, mean test sensitivity was highest in the Northern Europe group (95.6%) and lowest in the Southern Asia group (64.0%). The post-test residual carrier risk in the Northern Europe group was approximately 1 in 546, with only the Southern Asia group having a higher residual carrier risk of 1 in 179. CONCLUSION The Southern Asia group exhibited the lowest test sensitivity and the highest post-test residual carrier risk, surpassing that of the Northern Europe group. The inclusion or exclusion of VCC significantly impacted the calculated test sensitivities. Further research is suggested to better characterise CFTR variants in non-European ancestry groups and to determine which VCC, if any, should be included in carrier screening reports.
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Affiliation(s)
- Eric Lee
- Molecular Genetics, Virtus Diagnostics, Revesby, New South Wales, Australia
| | - Kaylee Orton
- Molecular Genetics, Virtus Diagnostics, Revesby, New South Wales, Australia
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Waheed N, Waris R, Naseer M, Razzaq A, Haider N, Shah AA, Ullah A. Mutational spectrum of CFTR in cystic fibrosis patients with gastrointestinal and hepatobiliary manifestations. Mol Biol Rep 2024; 51:573. [PMID: 38662334 DOI: 10.1007/s11033-024-09508-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 04/02/2024] [Indexed: 04/26/2024]
Abstract
BACKGROUND Cystic fibrosis (CF) is a rare and debilitating autosomal recessive disorder. It hampers the normal function of various organs and causes severe damage to the lungs, and digestive system leading to recurring pneumonia. Cf also affects reproductive health eventually may cause infertility. The disease manifests due to genetic aberrations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. This study aimed to screen for CFTR gene variants in Pakistani CF patients representing variable phenotypes. METHODS Clinical exome and Sanger sequencing were performed after clinical characterization of 25 suspected cases of CF (CF1-CF25). ACMG guidelines were followed to interpret the clinical significance of the identified variants. RESULTS Clinical investigations revealed common phenotypes such as pancreatic insufficiency, chest infections, chronic liver and lung diseases. Some patients also displayed symptoms like gastroesophageal reflux disease (GERD), neonatal cholestasis, acrodermatitis, diabetes mellitus, and abnormal malabsorptive stools. Genetic analysis of the 25 CF patients identified deleterious variants in the CFTR gene. Notably, 12% of patients showed compound heterozygous variants, while 88% had homozygous variants. The most prevalent variant was p. (Met1Thr or Met1?) at 24%, previously not reported in the Pakistani population. The second most common variant was p. (Phe508del) at 16%. Other variants, including p. (Leu218*), p. (Tyr569Asp), p. (Glu585Ter), and p. (Arg1162*) were also identified in the present study. Genetic analysis of one of the present patients showed a pathogenic variant in G6PD in addition to CFTR. CONCLUSION The study reports novel and reported variants in the CFTR gene in CF patients in Pakistani population having distinct phenotypes. It also emphasizes screening suspected Pakistani CF patients for the p. (Met1Thr) variant because of its increased observance and prevalence in the study. Moreover, the findings also signify searching for additional pathogenic variants in the genome of CF patients, which may modify the phenotypes. The findings contribute valuable information for the diagnosis, genetic counseling, and potential therapeutic strategies for CF patients in Pakistan.
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Affiliation(s)
- Nadia Waheed
- Department of Pediatrics, Institute of Medical Sciences, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Rehmana Waris
- Department of Pediatrics, Institute of Medical Sciences, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Maryam Naseer
- Department of Pediatrics, Institute of Medical Sciences, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Ayesha Razzaq
- Department of Pediatrics, Institute of Medical Sciences, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Nighat Haider
- Department of Pediatrics, Institute of Medical Sciences, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Abid Ali Shah
- Center for Medical Genetics and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China.
| | - Asmat Ullah
- Department of Biomedicine - Human Genetics, Aarhus University, Aarhus, Denmark.
- The Novo Nordisk Foundation Center for Genomic Mechanisms of Disease, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.
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Tiwari SK, Sharma R, Joshi P, Lodha R, Kabra SK. Knowledge, attitude, and practices among caregivers of children with Cystic Fibrosis. Pediatr Pulmonol 2024; 59:449-457. [PMID: 38014609 DOI: 10.1002/ppul.26772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 11/01/2023] [Accepted: 11/14/2023] [Indexed: 11/29/2023]
Abstract
BACKGROUND Caregivers have crucial role in the care of the children with Cystic Fibrosis (CF), but there is limited knowledge about their knowledge, attitude, and practices (KAP) regarding chronic disease. This pilot study aimed to validate a self-developed KAP questionnaire for caregivers of young children with CF in India and determine factors associated with KAP. MATERIALS AND METHODS A cross-sectional study was conducted among 95 caregivers of children with CF attending the specialty clinic of the pediatric outpatient department (OPD) in Northern India. Participants possessing certain characteristics such as willingness to participate and ability to understand Hindi or English language were enrolled in the study. Caregivers of children reported to the OPD with acute exacerbation requiring immediate hospitalization were excluded from the study. RESULTS The self-developed KAP questionnaire had good content validity (CVI- 0.87-1.0) and internal consistency (Cronbach's α coefficient = 0.70, 0.71, 0.75 respectively). The majority of participants belonged to the Good KAP group (85.3%), while the remaining were in the Poor KAP group (14.7%). A χ2 test showed that KAP clusters vary significantly with sociodemographic variables like gender, marital status, educational status and monthly family income (p < .05). A weak negative correlation was found between knowledge and attitude scores in the Good KAP group (p < .001). Multiple linear regression analysis showed that the KAP of the caregivers was significantly influenced by knowledge related to clinical manifestation and complications, and attitude. CONCLUSION All three sections of the KAP tool demonstrated good content validity and internal consistency. Caregivers had good knowledge, a positive attitude, and appropriate practices related to CF. However, targeted interventions are necessary to address specific areas for improvement, particularly for male caregivers with lower educational levels belonging to poor socioeconomic strata.
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Affiliation(s)
- Surya Kant Tiwari
- College of Nursing, All India Institute of Medical Sciences, Raebareli, Uttar Pradesh, India
| | - Rimple Sharma
- College of Nursing, All India Institute of Medical Sciences, New Delhi, India
| | - Poonam Joshi
- College of Nursing, All India Institute of Medical Sciences, Kalyani, West Bengal, India
| | - Rakesh Lodha
- Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - Sushil Kumar Kabra
- Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
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Hng SY, Thinakaran AS, Ooi CJ, Eg KP, Thong MK, Tae SK, Goh SH, Chew KS, Tan LT, Koh MT, Chong LA, Khalid F, Ng RT, Nathan AM, de Bruyne JA. Morbidity and treatment costs of cystic fibrosis in a middle-income country. Singapore Med J 2023:386391. [PMID: 37870036 DOI: 10.4103/singaporemedj.smj-2022-093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
Introduction : Asian children with cystic fibrosis (CF) managed in Malaysia have significant morbidity with limited access to life-sustaining treatments. We determined the morbidity and treatment cost of CF in a resource-limited country. Methods This cross-sectional study included all children diagnosed with CF in our centre. Data on clinical presentation, genetic mutation, serial spirometry results and complications were collected. Out-of-pocket (OOP) and healthcare costs over 1 year were retrieved for patients who were alive. Cohen's d and odds ratio (OR) were used to determine the effect size. Results Twenty-four patients were diagnosed with CF. Five patients died at a median (range) age of 18 (0.3-22) years. F508deletion (c. 1521_1523delCTT) was found in 20% of the alleles, while 89% of the variants were detected in nine patients. Body mass index (BMI) Z score was >-1.96 in 70.6% of patients. Two thirds (68%) were colonised with Pseudomonas aeruginosa, and this was associated with lower weight (P = 0.009) and BMI (P = 0.02) Z scores. Only 18% had FEV1 Z scores >-1.96. Early symptom onset (d = 0.74), delayed diagnosis (d = 2.07), a low FEF25-75 Z score (d = 0.82) and a high sweat conductance (d = 1.19) were associated with death. Inpatient cost was mainly from diagnostic tests, while medications contributed to half of the outpatient cost. Healthcare utilisation cost was catastrophic, amounting to 20% of the total income. Conclusion Asian children with CF suffer significant complications such as low weight, low lung function and shortened lifespan. P. aeruginosa colonisation was frequent and associated with poor growth. Healthcare cost to parents was catastrophic.
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Affiliation(s)
- Shih Ying Hng
- Department of Paediatrics, Paediatric Respiratory Unit, University of Malaya, Kuala Lumpur, Malaysia
| | | | - Chiou Jia Ooi
- Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kah Peng Eg
- Department of Paediatrics, Paediatric Respiratory Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Meow Keong Thong
- Department of Paediatrics, Genetics and Metabolism Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Sok Kun Tae
- Department of Paediatrics, Genetics and Metabolism Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Saw Huan Goh
- Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kee Seang Chew
- Department of Paediatrics, Paediatric Gastroenterology Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Lay Teng Tan
- Department of Paediatrics, Paediatric Infectious Disease Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Mia Tuang Koh
- Department of Paediatrics, Paediatric Infectious Disease Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Li Ai Chong
- Department of Paediatrics, Paediatric Palliative Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Farah Khalid
- Department of Paediatrics, Paediatric Palliative Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Ruey Teng Ng
- Department of Paediatrics, Paediatric Gastroenterology Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Anna Marie Nathan
- Department of Paediatrics, Paediatric Respiratory Unit, University of Malaya, Kuala Lumpur, Malaysia
| | - Jessie Anne de Bruyne
- Department of Paediatrics, Paediatric Respiratory Unit, University of Malaya, Kuala Lumpur, Malaysia
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Abubakar Bobbo K, Ahmad U, Chau DM, Nordin N, Abdullah S. A comprehensive review of cystic fibrosis in Africa and Asia. Saudi J Biol Sci 2023; 30:103685. [PMID: 37313453 PMCID: PMC10258508 DOI: 10.1016/j.sjbs.2023.103685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 04/30/2023] [Accepted: 05/15/2023] [Indexed: 06/15/2023] Open
Abstract
Cystic fibrosis (CF) was earlier thought to be a disease prevalent in the West among Caucasians. However, quite a number of recent studies have uncovered CF cases outside of this region, and reported hundreds of unique and novel variant forms of CFTR. Here, we discuss the evidence of CF in parts of the world earlier considered to be rare; Africa, and Asia. This review also highlighted the CFTR mutation variations and new mutations discovered in these regions. This discovery implies that the CF data from these regions were earlier underestimated. The inadequate awareness of the disease in these regions might have contributed towards the poor diagnostic facilities, under-diagnosis or/and under-reporting, and the lack of CF associated health policies. Overall, these regions have a high rate of infant, childhood and early adulthood mortality due to CF. Therefore, there is a need for a thorough investigation of CF prevalence and to identify unique and novel variant mutations within these regions in order to formulate intervention plans, create awareness, develop mutation specific screening kits and therapies to keep CF mortality at bay.
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Affiliation(s)
- Khadijat Abubakar Bobbo
- UPM-MAKNA Cancer Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
- Department of Human Anatomy College of Medical Sciences, Faculty of Medicine, Gombe State University, 760253 Gombe State, Nigeria
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
| | - Umar Ahmad
- Molecular Genetics Informatics, Department of Anatomy, Faculty of Basic Medical Sciences, Bauchi State University, 751105 Gadau, Nigeria
- Institute of Pathogen Genomics, Africa Centres for Disease Control and Prevention (Africa CDC), African Union Commission, P.O.Box 3243, Addis Ababa, Ethiopia
| | - De-Ming Chau
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
- Genetics & Regenerative Medicine Research Group, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
| | - Norshariza Nordin
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
- Genetics & Regenerative Medicine Research Group, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
| | - Syahril Abdullah
- UPM-MAKNA Cancer Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
- Genetics & Regenerative Medicine Research Group, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Selangor, Malaysia
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Vaidyanathan S, Trumbull AM, Bar L, Rao M, Yu Y, Sellers ZM. CFTR genotype analysis of Asians in international registries highlights disparities in the diagnosis and treatment of Asian patients with cystic fibrosis. Genet Med 2022; 24:2180-2186. [PMID: 35857025 DOI: 10.1016/j.gim.2022.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 06/22/2022] [Accepted: 06/23/2022] [Indexed: 10/17/2022] Open
Abstract
PURPOSE Cystic fibrosis (CF) is not well-characterized in Asians, potentially resulting in delayed diagnosis and poor prognosis. We characterized CF in Asian subgroups to address these disparities. METHODS De-identified ethnicity and CFTR variant data were obtained from the United States, United Kingdom, and Canadian CF registries. We measured the prevalence of CF, CFTR variant allele frequencies, effectiveness of screening panels, and eligibility for modulator therapies. RESULTS The prevalence of CF was 1 in 74,982 people (Canada) to 1 in 13,340 people (United Kingdom) for South Asians and 1 in 256,541 (Canada) to 1 in 52,563 (United Kingdom) for other Asians, suggesting 26,000 to 146,000 patients with CF in South Asia. p.(F508del) variant was markedly less frequent in Asians than in non-Hispanic Whites. Splicing and nonsense variants occurred at high allelic frequencies in Asians, resulting in 41% to 49% of South Asians and 21% to 39% of other Asians being ineligible for CFTR modulator therapies. Hologic/EU2v1 panels failed to identify 37% to 47% of South Asian and 23% to 46% of other Asian patients with CF. CONCLUSIONS Among Asians, CF appears to be more common in South Asians. A significant CF population may exist in South Asia. CFTR variants in South and other Asians markedly differ from non-Hispanic Whites causing inequities in newborn screening, diagnosis, and treatment. New strategies are necessary to mitigate these health care disparities.
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Affiliation(s)
| | | | - Lilly Bar
- Center for Asian Health Research and Education, Stanford University, Stanford, CA
| | - Manaeha Rao
- Center for Asian Health Research and Education, Stanford University, Stanford, CA
| | - Yunnan Yu
- Center for Asian Health Research and Education, Stanford University, Stanford, CA
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Leung ML, McAdoo S, Watson D, Stumm K, Harr M, Wang X, Chung CH, Mafra F, Nesbitt AI, Hakonarson H, Santani A. A Transparent Approach to Calculate Detection Rate and Residual Risk for Carrier Screening. J Mol Diagn 2021; 23:91-102. [PMID: 33349347 DOI: 10.1016/j.jmoldx.2020.10.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/05/2020] [Accepted: 10/14/2020] [Indexed: 01/25/2023] Open
Abstract
Carrier screening involves detection of carrier status for genes associated with recessive conditions. A negative carrier screening test result bears a nonzero residual risk (RR) for the individual to have an affected child. The RR depends on the prevalence of specific conditions and the detection rate (DR) of the test itself. Herein, we provide a detailed approach for calculating DR and RR. DR was calculated on the basis of the sum of disease allele frequencies (DAFs) of pathogenic variants found in published literature. As a proof of concept, DAF data for cystic fibrosis were compared with society guidelines. The DAF data calculated by this method were consistent with the published cystic fibrosis guideline. In addition, we compared DAF for four genes (ABCC8, ASPA, GAA, and MMUT) across three laboratories, and outlined the likely reasons for discrepancies between these laboratories. The utility of carrier screening is to support couples with information while making reproductive choices. Accurate development of DR and RR is therefore critical. The method described herein provides an unbiased and transparent process to collect, calculate, and report these data.
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Affiliation(s)
- Marco L Leung
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, Ohio; Department of Pathology, The Ohio State University College of Medicine, Columbus, Ohio; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio.
| | | | - Deborah Watson
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Departments of Pediatrics, The University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Kallyn Stumm
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Margaret Harr
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Xiang Wang
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Christine H Chung
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Fernanda Mafra
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Addie I Nesbitt
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Hakon Hakonarson
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Departments of Pediatrics, The University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Avni Santani
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Department of Pathology and Laboratory Medicine, The University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.
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Singh K, Bijarnia-Mahay S, Ramprasad VL, Puri RD, Nair S, Sharda S, Saxena R, Kohli S, Kulshreshtha S, Ganguli I, Gujral K, Verma IC. NGS-based expanded carrier screening for genetic disorders in North Indian population reveals unexpected results - a pilot study. BMC MEDICAL GENETICS 2020; 21:216. [PMID: 33138774 PMCID: PMC7607710 DOI: 10.1186/s12881-020-01153-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 10/20/2020] [Indexed: 12/25/2022]
Abstract
Background To determine the carrier frequency and pathogenic variants of common genetic disorders in the north Indian population by using next generation sequencing (NGS). Methods After pre-test counselling, 200 unrelated individuals (including 88 couples) were screened for pathogenic variants in 88 genes by NGS technology. The variants were classified as per American College of Medical Genetics criteria. Pathogenic and likely pathogenic variants were subjected to thorough literature-based curation in addition to the regular filters. Variants of unknown significance were not reported. Individuals were counselled explaining the implications of the results, and cascade screening was advised when necessary. Results Of the 200 participants, 52 (26%) were found to be carrier of one or more disorders. Twelve individuals were identified to be carriers for congenital deafness, giving a carrier frequency of one in 17 for one of the four genes tested (SLC26A4, GJB2, TMPRSS3 and TMC1 in decreasing order). Nine individuals were observed to be carriers for cystic fibrosis, with a frequency of one in 22. Three individuals were detected to be carriers for Pompe disease (frequency one in 67). None of the 88 couples screened were found to be carriers for the same disorder. The pathogenic variants observed in many disorders (such as deafness, cystic fibrosis, Pompe disease, Canavan disease, primary hyperoxaluria, junctional epidermolysis bullosa, galactosemia, medium chain acyl CoA deficiency etc.) were different from those commonly observed in the West. Conclusion A higher carrier frequency for genetic deafness, cystic fibrosis and Pompe disease was unexpected, and contrary to the generally held view about their prevalence in Asian Indians. In spite of the small sample size, this study would suggest that population-based carrier screening panels for India would differ from those in the West, and need to be selected with due care. Testing should comprise the study of all the coding exons with its boundaries in the genes through NGS, as all the variants are not well characterized. Only study of entire coding regions in the genes will detect carriers with adequate efficiency, in order to reduce the burden of genetic disorders in India and other resource poor countries. Supplementary Information The online version contains supplementary material available at 10.1186/s12881-020-01153-4.
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Affiliation(s)
- Kanika Singh
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Sunita Bijarnia-Mahay
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India.
| | | | - Ratna Dua Puri
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Sandhya Nair
- Medgenome Laboratories Pvt Ltd., Bangalore, India
| | | | - Renu Saxena
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Sudha Kohli
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Samarth Kulshreshtha
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Indrani Ganguli
- Institute of Obstetrics and Gynaecology, Sir Ganga Ram Hospital, New Delhi, India
| | - Kanwal Gujral
- Institute of Obstetrics and Gynaecology, Sir Ganga Ram Hospital, New Delhi, India
| | - Ishwar C Verma
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India.
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Semple A, Clark T, Allen NM, Krishnananthan T, Nwokoro C, Girodon E, Porzio M, Herzig M. Identification of a novel cystic fibrosis mutation in three patients of South Asian descent. CLINICAL RESPIRATORY JOURNAL 2020; 14:586-588. [PMID: 32043836 DOI: 10.1111/crj.13163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 02/08/2020] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The cystic fibrosis (CF) clinical profile and associated CFTR mutation spectrum is poorly understood in the South Asian population. This is likely due to the lack of diagnostic resources and the absence of a centralised CF database and screening programme, despite a relatively large proportion of the global population. METHODS Following identification of a previously unreported CFTR mutation (c.2805_2810delinsTCAGA; p.(Pro936Ginfs*6)) in a newly diagnosed patient of Indian descent, we interrogated national registries for other cases. RESULTS We identified three European-born subjects of South Asian descent with CF due to a novel CFTR mutation. All three subjects presented in infancy and each had a severe phenotype with intestinal complications as a presenting feature. Two subjects were diagnosed prior to the advent of universal screening. Preliminary genetic screening failed to identify the causative mutation in all three patients. CONCLUSION Our work highlights the value of extended or targeted genotyping in selected populations. It also demonstrates the benefit of routine collaboration between national registries. This will promote the identification of novel mutations; leading to greater understanding of genotype-phenotype associations, improved individual prognostication and ultimately the improved availability of novel precision therapies. This collaboration is essential if we are to achieve health equality for people with CF living in resource-limited settings.
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Affiliation(s)
- Aisling Semple
- Department of Paediatrics, National University of Ireland Galway, Ireland.,Department of Paediatrics, Galway University Hospital, Ireland
| | - Tara Clark
- Department of Genetics Counselling, Children's Health Ireland at Crumlin, Dublin 12, Ireland
| | - Nicholas M Allen
- Department of Paediatrics, National University of Ireland Galway, Ireland.,Department of Paediatrics, Galway University Hospital, Ireland
| | - Thanuja Krishnananthan
- Department of Paediatric Respiratory Medicine, Royal London Children's Hospital, London, UK
| | - Chinedu Nwokoro
- Department of Paediatric Respiratory Medicine, Royal London Children's Hospital, London, UK
| | - Emmanuelle Girodon
- Molecular Genetics Laboratory, Cochin Hospital, HUPC, APHP, Paris, France
| | - Michele Porzio
- Department of Respiratory Medicine, Nouvel Hôpital Civil, Strasbourg, France
| | - Mary Herzig
- Department of Paediatrics, National University of Ireland Galway, Ireland.,Department of Paediatrics, Galway University Hospital, Ireland
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Indika NLR, Vidanapathirana DM, Dilanthi HW, Kularatnam GAM, Chandrasiri NDPD, Jasinge E. Phenotypic spectrum and genetic heterogeneity of cystic fibrosis in Sri Lanka. BMC MEDICAL GENETICS 2019; 20:89. [PMID: 31126253 PMCID: PMC6534844 DOI: 10.1186/s12881-019-0815-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 04/24/2019] [Indexed: 11/13/2022]
Abstract
Background Cystic fibrosis has been largely under-diagnosed and thus, limited data is available on the incidence of cystic fibrosis in Sri Lanka. Our aim is to describe the phenotypic and genotypic spectrum of children with cystic fibrosis in Sri Lanka. Case presentation This report describes 10 unrelated cystic fibrosis cases with phenotypic features of cystic fibrosis and abnormal or intermediate sweat tests. The most common phenotypic features in this sample of symptomatic patients were persistent or recurrent lower respiratory tract infections, failure to thrive and Pseudo-Bartter syndrome. Altogether 7 cystic fibrosis causing mutations were identified in 10 patients. Except delta F508 which is the commonest mutation worldwide all the other mutations detected in Sri Lankan patients are rare mutations. 1161delC and V456A detected in our patients are South Asian mutations. The other mutations such as [C.1282C > G; C.2738A > G], C.53 + 1G > C, 2184insA and a deletion encompassing exons 4 to 11 have been reported previously from European patients with cystic fibrosis. Conclusion These cases highlight the importance of considering the diagnosis of cystic fibrosis in children and young adults presenting with persistent respiratory tract infections associated with severe malnutrition and Pseudo-Bartter syndrome, especially in low income countries where newborn screening for cystic fibrosis is not available. The spectrum of CFTR mutations in Sri Lanka is heterogeneous and possibly linked to genetic flow from Indian subcontinent and Europe. The common mutations should be identified by sequencing the entire CFTR gene in adequate number of cystic fibrosis patients in order to design a mutation panel for common regional mutations.
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Affiliation(s)
- Neluwa Liyanage Ruwan Indika
- Department of Biochemistry, Faculty of Medical Sciences, University of Sri Jayewardenepura, Nugegoda, Sri Lanka.
| | | | - Hewa Warawitage Dilanthi
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Colombo, Colombo 8, Sri Lanka
| | | | | | - Eresha Jasinge
- Department of Chemical Pathology, Lady Ridgeway Hospital for Children, Colombo 8, Sri Lanka
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Qiu L, Yang F, He Y, Yuan H, Zhou J. Clinical characterization and diagnosis of cystic fibrosis through exome sequencing in Chinese infants with Bartter-syndrome-like hypokalemia alkalosis. Front Med 2018. [PMID: 29520692 DOI: 10.1007/s11684-017-0567-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Cystic fibrosis (CF) is a fatal autosomal-recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. CF is characterized by recurrent pulmonary infection with obstructive pulmonary disease. CF is common in the Caucasian population but is rare in the Chinese population. The symptoms of early-stage CF are often untypical and may sometimes manifest as Bartter syndrome (BS)-like hypokalemic alkalosis. Therefore, the ability of doctors to differentiate CF from BS-like hypokalemic alkalosis in Chinese infants is a great challenge in the timely and accurate diagnosis of CF. In China, sporadic CF has not been diagnosed in children younger than three years of age to date. Three infants, who were initially admitted to our hospital over the period of June 2013 to September 2014 with BS-like hypokalemic alkalosis, were diagnosed with CF through exome sequencing and sweat chloride measurement. The compound heterozygous mutations of the CFTR gene were detected in two infants, and a homozygous missense mutation was found in one infant. Among the six identified mutations, two are novel point mutations (c.1526G > C and c.3062C > T) that are possibly pathogenic. The three infants are the youngest Chinese patients to have been diagnosed with sporadic CF at a very early stage. Follow-up examination showed that all of the cases remained symptom-free after early intervention, indicating the potential benefit of very early diagnosis and timely intervention in children with CF. Our results demonstrate the necessity of distinguishing CF from BS in Chinese infants with hypokalemic alkalosis and the significant diagnostic value of powerful exome sequencing for rare genetic diseases. Furthermore, our findings expand the CFTR mutation spectrum associated with CF.
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Affiliation(s)
- Liru Qiu
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430030, China
| | - Fengjie Yang
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430030, China
| | - Yonghua He
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430030, China
| | - Huiqing Yuan
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430030, China
| | - Jianhua Zhou
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430030, China.
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Serious fungal infections in Pakistan. Eur J Clin Microbiol Infect Dis 2017; 36:949-956. [PMID: 28161741 DOI: 10.1007/s10096-017-2919-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 12/21/2016] [Indexed: 11/25/2022]
Abstract
The true burden of fungal infection in Pakistan is unknown. High-risk populations for fungal infections [tuberculosis (TB), diabetes, chronic respiratory diseases, asthma, cancer, transplant and human immunodeficiency virus (HIV) infection] are numerous. Here, we estimate the burden of fungal infections to highlight their public health significance. Whole and at-risk population estimates were obtained from the WHO (TB), BREATHE study (COPD), UNAIDS (HIV), GLOBOCAN (cancer) and Heartfile (diabetes). Published data from Pakistan reporting fungal infections rates in general and specific populations were reviewed and used when applicable. Estimates were made for the whole population or specific populations at risk, as previously described in the LIFE methodology. Of the 184,500,000 people in Pakistan, an estimated 3,280,549 (1.78%) are affected by a serious fungal infection, omitting all cutaneous infection, oral candidiasis and allergic fungal sinusitis, which we could not estimate. Compared with other countries, the rates of candidaemia (21/100,000) and mucormycosis (14/100,000) are estimated to be very high, and are based on data from India. Chronic pulmonary aspergillosis rates are estimated to be high (39/100,000) because of the high TB burden. Invasive aspergillosis was estimated to be around 5.9/100,000. Fungal keratitis is also problematic in Pakistan, with an estimated rate of 44/100,000. Pakistan probably has a high rate of certain life- or sight-threatening fungal infections.
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Singh M, Rebordosa C, Bernholz J, Sharma N. Epidemiology and genetics of cystic fibrosis in Asia: In preparation for the next-generation treatments. Respirology 2015; 20:1172-81. [PMID: 26437683 DOI: 10.1111/resp.12656] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 06/18/2015] [Accepted: 07/27/2015] [Indexed: 12/11/2022]
Abstract
Cystic fibrosis (CF) in the Asian population is less frequently reported due to under-diagnosis and lack of centralized CF patient registries. Clinical studies on CF cases from Asia have documented a severe course of the disease. The spectrum of the cystic fibrosis transmembrane conductance regulator (CFTR) variants in this population is quite heterogeneous. In total, 166 variants have been reported on approximately 3700 Asian CF chromosomes. The frequency of F508del among Asians is low compared with Caucasians. Recent in vitro studies have shown promise of small molecule correction and potentiation of 45 different CFTR variants. Of these variants, 16 (including G551D and F508del) have also been observed among Asian CF individuals. We suggest undertaking molecular studies extensively to annotate CFTR variants that will help Asian CF individuals to benefit from the precision medicine gaining momentum in the Western countries.
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Affiliation(s)
- Meenu Singh
- Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Cristina Rebordosa
- Department of Epidemiology, Division of Drug Safety and Epidemiology, Novartis Farmaceutica S.A., Barcelona, Spain
| | - Juliane Bernholz
- Department of Development, Division of Pharma, Novartis Pharma AG, Basel, Switzerland
| | - Neeraj Sharma
- McKusick-Nathans Institute of Genetic Medicine and Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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An empirical estimate of carrier frequencies for 400+ causal Mendelian variants: results from an ethnically diverse clinical sample of 23,453 individuals. Genet Med 2012; 15:178-86. [PMID: 22975760 PMCID: PMC3908551 DOI: 10.1038/gim.2012.114] [Citation(s) in RCA: 192] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Purpose: Recent developments in genomics have led to expanded carrier screening panels capable of assessing hundreds of causal mutations for genetic disease. This new technology enables simultaneous measurement of carrier frequencies for many diseases. As the resultant rank-ordering of carrier frequencies impacts the design and prioritization of screening programs, the accuracy of this ranking is a public health concern. Methods: A total of 23,453 individuals from many obstetric, genetics, and infertility clinics were referred for routine recessive disease carrier screening. Multiplex carrier screening was performed and results were aggregated for this study. Results: Twenty-four percent of individuals were identified as carriers for at least one of 108 disorders, and 5.2% were carriers for multiple disorders. We report tabulations of carrier frequency by self-identified ethnicity and disease. Conclusion: To our knowledge, this study of a large, ethnically diverse clinical sample provides the most accurate measurements to date of carrier frequencies for hundreds of recessive alleles. The study also yields information on the clinical considerations associated with routine use of expanded panels and provides support for a pan-ethnic screening paradigm that minimizes the use of “racial” categories by the physician, as recommended by recent guidelines.
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Uppaluri L, England S, Scanlin T. Clinical evidence that V456A is a Cystic Fibrosis causing mutation in South Asians. J Cyst Fibros 2012; 11:312-5. [DOI: 10.1016/j.jcf.2012.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 02/06/2012] [Accepted: 02/14/2012] [Indexed: 10/28/2022]
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Nathan AM, Thong MK, deBruyne J, Ariffin H. First study of the F508del mutation in Malaysian children diagnosed with cystic fibrosis. J Paediatr Child Health 2011; 47:573-5. [PMID: 21843195 DOI: 10.1111/j.1440-1754.2011.02149.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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17
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Li W, Sun L, Corey M, Zou F, Lee S, Cojocaru AL, Taylor C, Blackman SM, Stephenson A, Sandford AJ, Dorfman R, Drumm ML, Cutting GR, Knowles MR, Durie P, Wright FA, Strug LJ. Understanding the population structure of North American patients with cystic fibrosis. Clin Genet 2011; 79:136-46. [PMID: 20681990 PMCID: PMC2995003 DOI: 10.1111/j.1399-0004.2010.01502.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
It is generally presumed that the cystic fibrosis (CF) population is relatively homogeneous, and predominantly of European origin. The complex ethnic make-up observed in the CF patients collected by the North American CF Modifier Gene Consortium has brought this assumption into question, and suggested the potential for population substructure in the three CF study samples collected from North America. It is well appreciated that population substructure can result in spurious genetic associations. To understand the ethnic composition of the North American CF population, and to assess the need for population structure adjustment in genetic association studies with North American CF patients, genome-wide single-nucleotide polymorphisms on 3076 unrelated North American CF patients were used to perform population structure analyses. We compared self-reported ethnicity to genotype-inferred ancestry, and also examined whether geographic distribution and cystic fibrosis transmembrane regulator (CFTR) mutation type could explain the population structure observed. Although largely Caucasian, our analyses identified a considerable number of CF patients with admixed African-Caucasian, Mexican-Caucasian and Indian-Caucasian ancestries. Population substructure was present and comparable across the three studies of the consortium. Neither geographic distribution nor CFTR mutation type explained the population structure. Given the ethnic diversity of the North American CF population, it is essential to carefully detect, estimate and adjust for population substructure to guard against potential spurious findings in CF genetic association studies. Other Mendelian diseases that are presumed to predominantly affect single ethnic groups may also benefit from careful analysis of population structure.
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Affiliation(s)
- W Li
- Child Health Evaluative Sciences Program, Hospital for Sick Children, Toronto, M5G 1X8, ON, Canada
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Abstract
Cystic fibrosis is a common autosomal recessive disorder usually found in population of white Caucasian descent. Now it is well documented the presence of CF disease in India with the advancement of laboratory testing. As once it was thought non existence of this disease in our population. Most of the phenotype of CF disease was in accordance of western population. Genetic analysis of CFTR gene in Indian CF patients revealed that most common mutation was delta F508 mutation. However, it was less than Caucasian population. CFTR mutations are also a causative factor in the pathogenesis of male infertility due to obstructive azoospermia. There are two most common mutation viz. IVS8-T5 and delta F508 which are responsible for congenital absence of vas deferens in male infertility patients. Elevated levels of sweat chloride at two occasions along with the presence of two mutations in CFTR gene was gold standard method for diagnosis of CF disease. It is noteworthy here that due to magnitude of Indian population, the total CF disease load would be more than many European countries. Clinical data demonstrate the prevalence of both classical and genetic form of CF in India.
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Abstract
The past 50 years have seen great progress in the understanding and treatment of classic growth disorders. Advances such as the recognition of hormone receptor defects, the development of recombinant growth hormone, and the expanding awareness of epigenetic phenomena affecting growth are among these great achievements. Yet growth failure remains a pervasive problem among children with complex health conditions, such as survivors of childhood cancers, premature infants, organ transplant recipients, and children with cystic fibrosis. The significant increases in life expectancy among these groups underscores the potential consequences of poor growth, whether due to the underlying conditions or medical treatments, as they may have long-lasting effects into adulthood. The ongoing contributions of human biologists to the study of human growth remain essential in the recognition and treatment of growth disorders, by defining normal patterns of growth and body composition, the interplay of growth and maturation, the role of environmental, behavioral and genetic factors, and the long-term consequences of growth patterns. Examples will be given based on two common genetic disorders, cystic fibrosis and sickle-cell anemia, to highlight the relationships between growth failure, survival, and malnutrition. Also, a study of bone mineral accretion in children with cystic fibrosis will illustrate the importance of understanding patterns of growth in healthy children, and their application in the diagnosis and management of children with chronic disease. These examples accentuate the need for continued participation of human biologists in the study of growth and development and the care of children.
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Affiliation(s)
- Babette Zemel
- Division of Gastroenterology, Hepatology and Nutrition, The Children's Hospital of Philadelphia, Department of Pediatrics, The University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
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Lin CJ, Chang SP, Ke YY, Chiu HY, Tsao LY, Chen M. Phenotype and genotype of two Taiwanese cystic fibrosis siblings and a survey of delta F508 in East Asians. Pediatr Neonatol 2008; 49:240-4. [PMID: 19166122 DOI: 10.1016/s1875-9572(09)60018-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Cystic fibrosis (CF) is considered to be a rare disease in Asians. We report two cases of CF in a 5-year-old girl and her newborn brother. They are of mixed parentage: a Taiwanese mother and an Australian father. METHODS A comprehensive mutational analysis of the cystic fibrosis transmembrane conductance regulator (CFTR) gene was completed. Literature was reviewed for delta F508 in East Asians. RESULTS Two mutation sites were identified in the siblings. The carrier status of their parents and elder brother were also confirmed: heterozygous delta F508 mutation from the father; 13 TG repeats in the IVS8-5T from the mother. An update of delta F508 mutation reported in East Asian patients from various ethnicities is included; most of them were of mixed parentage. CONCLUSION These two cases are the first report of cystic fibrosis associated with a delta F508 mutation in a Taiwanese patient attributable to a mutation most commonly seen in Caucasians. We found that the delta F508 mutation is of western origin. Asian patients are seldom found with this mutation unless they are of mixed parentage. Our findings provide further evidence that different ethnicities have their own set of CFTR mutations.
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Affiliation(s)
- Chao-Jen Lin
- Division of Pediatric Infectious Diseases, Changhua Christian Children's Hospital, Changhua, Taiwan, ROC
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Sharma N, Singh M, Kaur G, Thapa BR, Prasad R. Identification and characterization of CFTR gene mutations in Indian CF patients. Ann Hum Genet 2008; 73:26-33. [PMID: 18782298 DOI: 10.1111/j.1469-1809.2008.00477.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. This study was performed on Indian CF patients (n = 50) to investigate the spectrum of mutations in the CFTR gene and their association with intragenic and extragenic marker haplotypes. We report identification of 14 previously known and eight novel mutations, namely 3986-3987delC, 876-6del4, 1792InsA, L69H, S158N, Q493L, I530L and E1329Q. The frequency of delta F508 was found to be 27%. Absolute linkage between delta F508 and the KM.19-GATT-TUB9-M470V-T854T haplotype (2-2-1-1-1) predicts a relatively recent appearance of delta F508 in Indian CF patients. Low frequency of delta F508 mutation and detection of eight novel and thirteen rare mutations reflect a heterogeneous spectrum of mutations in Indian CF patients. Failure to detect mutations in 34% of alleles indicates the possible presence of gross deletions involving one or more exons or may indicate the location of the molecular defects in either the noncoding parts of the gene or in the promoter region, which warrants analysis of those regions.
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Affiliation(s)
- N Sharma
- Department of Biochemistry, Post Graduate Institute of Medical Education and Research, Chandigarh, India-160012
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22
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Steinraths M, Vallance HD, Davidson AGF. Delays in diagnosing cystic fibrosis: can we find ways to diagnose it earlier? CANADIAN FAMILY PHYSICIAN MEDECIN DE FAMILLE CANADIEN 2008; 54:877-883. [PMID: 18556497 PMCID: PMC2427000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVE To describe the clinical presentation and delays in diagnosis of patients with cystic fibrosis (CF) with the goal of raising physicians' awareness of CF and establishing baseline data for comparison with outcomes of patients who undergo newborn screening for CF. DESIGN Retrospective review of hospital medical records and CF clinic charts of newly diagnosed CF patients younger than 18 years who had attended the CF clinic at the BC Children's Hospital in Vancouver between January 1, 1993, and January 1, 2005. Age at diagnosis of CF was ascertained for 24 adult patients diagnosed during the same period from the CF clinic at St Paul's Hospital in Vancouver, BC. SETTING Cystic fibrosis clinic at the BC Children's Hospital. PARTICIPANTS All newly diagnosed CF patients from mainland BC and northern Vancouver Island (N = 122). MAIN OUTCOME MEASURES Mean age at diagnosis; mean delay in diagnosis; weight and height or length at diagnosis; vitamin E status; mean head circumference; types of symptoms before diagnosis; Pseudomonas aeruginosa status; and number of days spent in tertiary care hospitals before diagnosis. RESULTS Excluding the adult patients and patients with meconium ileus, mean age at diagnosis of CF was 3.6 years, and mean delay in diagnosis after first symptoms was 2.1 years. Weight at diagnosis was < or = 5th percentile in 37% of cases, and height or length was < or = 5th percentile in 26% of cases. Excluding those with meconium ileus and those taking vitamin E supplementation, 70% of the children were vitamin E deficient at diagnosis. These children had a mean head circumference substantially smaller than that of children who had adequate levels of vitamin E. About 95% of children had gastrointestinal (GI) or malnutrition symptoms before diagnosis; 15% had GI symptoms only. About 81% of patients had respiratory symptoms, but only 4% had respiratory symptoms as the only evidence of CF before diagnosis. Around 9% were colonized with P aeruginosa at diagnosis. Before being diagnosed, 79% of patients had required tertiary care hospitalization for a group total of 320 hospital days. CONCLUSION Considerable delays in diagnosis of children with CF occur when the disease is identified solely on clinical presentation. Morbidity is often severe enough to require hospital admission before CF is diagnosed. Symptoms that occurred before diagnosis were often GI or malnutritional in nature rather than respiratory, but all such symptoms were associated with diagnostic delays.
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Abstract
Cystic fibrosis (CF) was considered to be non-existent in Indian subcontinent. Reports in last one decade have suggested that cystic fibrosis occurs in India but its precise magnitude is not known. Studies on migrant Indian population in United States and United Kingdom estimate frequency of CF as 1:10,000 to 1:40,000. The clinical features are similar to that reported in Caucasian population. CF in Indian children is usually diagnosed late and in advanced stage. Children are more malnourished and may have clinically evident deficiency of fat soluble vitamins. The frequency of clubbing, colonization with Pseudomonas, and laboratory evidence of pseudo-Bartter syndrome is relatively more at the time of diagnosis. Diagnostic facilities in form of sweat chloride estimation and genetic studies are not available readily. Mutation profile is different. The frequency of common mutation F508del in Indian children is between 19% and 34%. Other mutations are heterogeneous. Management of CF in India is difficult due to less number of trained manpower, limited availability, and high cost of pharmacologic agents. The determinants of early death include: severe malnutrition and colonization with Pseudomonas at the time of diagnosis, more than four episodes of lower respiratory infection per year and age of onset of symptoms before 2 months of age. To conclude, CF does occur in India; however, precise magnitude of problem is not known. There is need to create awareness amongst pediatricians, developing diagnostic facilities, and management protocols based on locally available resources.
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Affiliation(s)
- S K Kabra
- Department of Pediatrics, All India Institute of Medical Sciences, New Delhi 110029, India.
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Dupuis A, Hamilton D, Cole DEC, Corey M. Cystic fibrosis birth rates in Canada: a decreasing trend since the onset of genetic testing. J Pediatr 2005; 147:312-5. [PMID: 16182667 DOI: 10.1016/j.jpeds.2005.06.043] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2005] [Revised: 06/03/2005] [Accepted: 06/22/2005] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To estimate cystic fibrosis (CF) birth rates in Canada from 1971 to 2000 and to assess the population impact of genetic testing in families with a history of CF, after identification of the CF transmembrane conductance regulator gene in 1989. STUDY DESIGN Age-at-diagnosis data were obtained from the Canadian Cystic Fibrosis Foundation Patient Data Registry and Canadian births for the corresponding years from Canadian Vital Statistics. Estimates of the CF birth rate in each year were based on a nonparametric model that allows the birth rate to vary across the years and adjusts for censoring of currently undiagnosed patients. RESULTS The overall CF birth rate from 1971-1987 was 1/2714 with no increasing or decreasing trend. Beginning in 1988, 1 year before identification of the CF transmembrane conductance regulator gene, estimated CF birth rates followed a linear decline to an estimated rate of 1/3608 in 2000. CF birth rates may have stabilized in the last few years, but further decline may occur with implementation of carrier screening in the general population. CONCLUSIONS These results demonstrate the temporal association of genetic testing and declining CF birth rates in Canada. They may assist in decisions relating to the allocation of resources for prenatal and neonatal CF screening programs.
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Affiliation(s)
- Annie Dupuis
- The Hospital for Sick Children and University of Toronto, Toronto, Ontario, Canada
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