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Farcy S, Hachour H, Bahi-Buisson N, Passemard S. Genetic Primary Microcephalies: When Centrosome Dysfunction Dictates Brain and Body Size. Cells 2023; 12:1807. [PMID: 37443841 PMCID: PMC10340463 DOI: 10.3390/cells12131807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 06/04/2023] [Accepted: 06/13/2023] [Indexed: 07/15/2023] Open
Abstract
Primary microcephalies (PMs) are defects in brain growth that are detectable at or before birth and are responsible for neurodevelopmental disorders. Most are caused by biallelic or, more rarely, dominant mutations in one of the likely hundreds of genes encoding PM proteins, i.e., ubiquitous centrosome or microtubule-associated proteins required for the division of neural progenitor cells in the embryonic brain. Here, we provide an overview of the different types of PMs, i.e., isolated PMs with or without malformations of cortical development and PMs associated with short stature (microcephalic dwarfism) or sensorineural disorders. We present an overview of the genetic, developmental, neurological, and cognitive aspects characterizing the most representative PMs. The analysis of phenotypic similarities and differences among patients has led scientists to elucidate the roles of these PM proteins in humans. Phenotypic similarities indicate possible redundant functions of a few of these proteins, such as ASPM and WDR62, which play roles only in determining brain size and structure. However, the protein pericentrin (PCNT) is equally required for determining brain and body size. Other PM proteins perform both functions, albeit to different degrees. Finally, by comparing phenotypes, we considered the interrelationships among these proteins.
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Affiliation(s)
- Sarah Farcy
- UMR144, Institut Curie, 75005 Paris, France;
- Inserm UMR-S 1163, Institut Imagine, 75015 Paris, France
| | - Hassina Hachour
- Service de Neurologie Pédiatrique, DMU INOV-RDB, APHP, Hôpital Robert Debré, 75019 Paris, France;
| | - Nadia Bahi-Buisson
- Service de Neurologie Pédiatrique, DMU MICADO, APHP, Hôpital Necker Enfants Malades, 75015 Paris, France;
- Université Paris Cité, Inserm UMR-S 1163, Institut Imagine, 75015 Paris, France
| | - Sandrine Passemard
- Service de Neurologie Pédiatrique, DMU INOV-RDB, APHP, Hôpital Robert Debré, 75019 Paris, France;
- Université Paris Cité, Inserm UMR 1141, NeuroDiderot, 75019 Paris, France
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Kristofova M, Ori A, Wang ZQ. Multifaceted Microcephaly-Related Gene MCPH1. Cells 2022; 11:cells11020275. [PMID: 35053391 PMCID: PMC8774270 DOI: 10.3390/cells11020275] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 12/19/2022] Open
Abstract
MCPH1, or BRIT1, is often mutated in human primary microcephaly type 1, a neurodevelopmental disorder characterized by a smaller brain size at birth, due to its dysfunction in regulating the proliferation and self-renewal of neuroprogenitor cells. In the last 20 years or so, genetic and cellular studies have identified MCPH1 as a multifaceted protein in various cellular functions, including DNA damage signaling and repair, the regulation of chromosome condensation, cell-cycle progression, centrosome activity and the metabolism. Yet, genetic and animal model studies have revealed an unpredicted essential function of MPCH1 in gonad development and tumorigenesis, although the underlying mechanism remains elusive. These studies have begun to shed light on the role of MPCH1 in controlling various pathobiological processes of the disorder. Here, we summarize the biological functions of MCPH1, and lessons learnt from cellular and mouse models of MCPH1.
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Affiliation(s)
- Martina Kristofova
- Leibniz Institute on Aging—Fritz Lipmann Institute (FLI), Beutenbergstrasse 11, 07745 Jena, Germany; (M.K.); (A.O.)
| | - Alessandro Ori
- Leibniz Institute on Aging—Fritz Lipmann Institute (FLI), Beutenbergstrasse 11, 07745 Jena, Germany; (M.K.); (A.O.)
| | - Zhao-Qi Wang
- Leibniz Institute on Aging—Fritz Lipmann Institute (FLI), Beutenbergstrasse 11, 07745 Jena, Germany; (M.K.); (A.O.)
- Faculty of Biological Sciences, Friedrich-Schiller University of Jena, Bachstrasse 18k, 07743 Jena, Germany
- Correspondence: ; Tel.: +49-3641-656415; Fax: +49-3641-656335
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Wong PCM, Kang X, Wong KHY, So HC, Choy KW, Geng X. ASPM-lexical tone association in speakers of a tone language: Direct evidence for the genetic-biasing hypothesis of language evolution. SCIENCE ADVANCES 2020; 6:eaba5090. [PMID: 32537487 PMCID: PMC7253162 DOI: 10.1126/sciadv.aba5090] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/20/2020] [Indexed: 05/12/2023]
Abstract
How language has evolved into more than 7000 varieties today remains a question that puzzles linguists, anthropologists, and evolutionary scientists. The genetic-biasing hypothesis of language evolution postulates that genes and language features coevolve, such that a population that is genetically predisposed to perceiving a particular linguistic feature would tend to adopt that feature in their language. Statistical studies that correlated a large number of genetic variants and linguistic features not only generated this hypothesis but also specifically pinpointed a linkage between ASPM and lexical tone. However, there is currently no direct evidence for this association and, therefore, the hypothesis. In an experimental study, we provide evidence to link ASPM with lexical tone perception in a sample of over 400 speakers of a tone language. In addition to providing the first direct evidence for the genetic-biasing hypothesis, our results have implications for further studies of linguistic anthropology and language disorders.
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Affiliation(s)
- Patrick C. M. Wong
- Department of Linguistics and Modern Languages, The Chinese University of Hong Kong, Shatin, Hong Kong
- Brain and Mind Institute, The Chinese University of Hong Kong, Shatin, Hong Kong
- Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Xin Kang
- Department of Linguistics and Modern Languages, The Chinese University of Hong Kong, Shatin, Hong Kong
- Brain and Mind Institute, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Kay H. Y. Wong
- Department of Linguistics and Modern Languages, The Chinese University of Hong Kong, Shatin, Hong Kong
- Brain and Mind Institute, The Chinese University of Hong Kong, Shatin, Hong Kong
- Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Hon-Cheong So
- Brain and Mind Institute, The Chinese University of Hong Kong, Shatin, Hong Kong
- School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Kwong Wai Choy
- Brain and Mind Institute, The Chinese University of Hong Kong, Shatin, Hong Kong
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Xiujuan Geng
- Department of Linguistics and Modern Languages, The Chinese University of Hong Kong, Shatin, Hong Kong
- Brain and Mind Institute, The Chinese University of Hong Kong, Shatin, Hong Kong
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Singh SV, Staes N, Guevara EE, Schapiro SJ, Ely JJ, Hopkins WD, Sherwood CC, Bradley BJ. Evolution of ASPM coding variation in apes and associations with brain structure in chimpanzees. GENES BRAIN AND BEHAVIOR 2019; 18:e12582. [PMID: 31119860 DOI: 10.1111/gbb.12582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 05/07/2019] [Accepted: 05/21/2019] [Indexed: 12/21/2022]
Abstract
Studying genetic mechanisms underlying primate brain morphology can provide insight into the evolution of human brain structure and cognition. In humans, loss-of-function mutations in the gene coding for ASPM (Abnormal Spindle Microtubule Assembly) have been associated with primary microcephaly, which is defined by a significantly reduced brain volume, intellectual disability and delayed development. However, less is known about the effects of common ASPM variation in humans and other primates. In this study, we characterized the degree of coding variation at ASPM in a large sample of chimpanzees (N = 241), and examined potential associations between genotype and various measures of brain morphology. We identified and genotyped five non-synonymous polymorphisms in exons 3 (V588G), 18 (Q2772K, K2796E, C2811Y) and 27 (I3427V). Using T1-weighted magnetic resonance imaging of brains, we measured total brain volume, cerebral gray and white matter volume, cerebral ventricular volume, and cortical surface area in the same chimpanzees. We found a potential association between ASPM V588G genotype and cerebral ventricular volume but not with the other measures. Additionally, we found that chimpanzee, bonobo, and human lineages each independently show a signature of accelerated ASPM protein evolution. Overall, our results suggest the potential effects of ASPM variation on cerebral cortical development, and emphasize the need for further functional studies. These results are the first evidence suggesting ASPM variation might play a role in shaping natural variation in brain structure in nonhuman primates.
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Affiliation(s)
- Sheel V Singh
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, District of Columbia
| | - Nicky Staes
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, District of Columbia.,Behavioural Ecology & Ecophysiology Group, Department of Biology, University of Antwerp, Antwerp, Belgium.,Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium
| | - Elaine E Guevara
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, District of Columbia
| | - Steven J Schapiro
- Michael E. Keeling Center for Comparative Medicine and Research, University of Texas MD Anderson Cancer Center, Bastrop, Texas
| | | | - William D Hopkins
- Michael E. Keeling Center for Comparative Medicine and Research, University of Texas MD Anderson Cancer Center, Bastrop, Texas
| | - Chet C Sherwood
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, District of Columbia
| | - Brenda J Bradley
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, District of Columbia
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Pierzak-Sominka J, Skonieczna-Żydecka K, Rudnicki J, Karakiewicz B. The Impact of rs3762271 and rs930557 Polymorphisms of ASPM and MCPH1 Genes on the Anatomy and Function of the Brain. Biol Res Nurs 2016; 18:386-93. [PMID: 26912502 DOI: 10.1177/1099800416630621] [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: 11/17/2022]
Abstract
The ASPM and MCPH1 genes are involved in early neurogenesis and are thus potential candidates for affecting the formation of the anatomical and functional characteristics of the brain. However, the results of studies to date have been conflicting, an issue for which the factor of ethnicity may be responsible. We aimed to examine whether the rs3762271 and rs930557 polymorphisms of these two genes can influence brain anatomy and function. We enrolled 97 Caucasian neonates, with males predominating (53.6%). The anatomy of the brain was examined using ultrasound, while Doppler ultrasound was used to establish the blood flow indices in particular brain blood vessels. Genetic analysis was carried out using the polymerase chain reaction-restriction fragment length polymorphism method. The CC and AA homozygotes of rs3762271 were more common in males. The CC genotype of rs3762271 was significantly associated with birth weight (pRE = .03) and body length (pRE = .02). One mutant allele of rs3762271 was significantly associated with higher values of maximum (Vmax, p = .04), minimum (Vmin, p = .04), and average (Vmean, p = .02) speed in the pericallosal artery in newborns of both genders. Similar relationships were found in females only (Vmax p = .03, Vmean p = .02). The CC genotype of rs930557 was more frequently observed in male infants, but no impact on any anthropometric indices or anatomical and functional parameters of the brain was established. The ASPM gene may play a role in shaping the functional parameters of the brain in Caucasians.
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Affiliation(s)
| | | | - Jacek Rudnicki
- Department of Newborn Pathology, Pomeranian Medical University, Szczecin, Poland
| | - Beata Karakiewicz
- Department of Public Health, Pomeranian Medical University, Szczecin, Poland
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Pulvers JN, Journiac N, Arai Y, Nardelli J. MCPH1: a window into brain development and evolution. Front Cell Neurosci 2015; 9:92. [PMID: 25870538 PMCID: PMC4376118 DOI: 10.3389/fncel.2015.00092] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/28/2015] [Indexed: 12/21/2022] Open
Abstract
The development of the mammalian cerebral cortex involves a series of mechanisms: from patterning, progenitor cell proliferation and differentiation, to neuronal migration. Many factors influence the development of the cerebral cortex to its normal size and neuronal composition. Of these, the mechanisms that influence the proliferation and differentiation of neural progenitor cells are of particular interest, as they may have the greatest consequence on brain size, not only during development but also in evolution. In this context, causative genes of human autosomal recessive primary microcephaly, such as ASPM and MCPH1, are attractive candidates, as many of them show positive selection during primate evolution. MCPH1 causes microcephaly in mice and humans and is involved in a diverse array of molecular functions beyond brain development, including DNA repair and chromosome condensation. Positive selection of MCPH1 in the primate lineage has led to much insight and discussion of its role in brain size evolution. In this review, we will present an overview of MCPH1 from these multiple angles, and whilst its specific role in brain size regulation during development and evolution remain elusive, the pieces of the puzzle will be discussed with the aim of putting together the full picture of this fascinating gene.
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Affiliation(s)
| | - Nathalie Journiac
- U1141 Inserm Paris, France ; Université Paris Diderot, Sorbonne Paris Cité, UMRS 1141 Paris, France
| | - Yoko Arai
- Institut Jacques Monod, CNRS UMR 7592, Université Paris Diderot, Sorbonne Paris Cité Paris, France
| | - Jeannette Nardelli
- U1141 Inserm Paris, France ; Université Paris Diderot, Sorbonne Paris Cité, UMRS 1141 Paris, France
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Dobson-Stone C, Polly P, Korgaonkar MS, Williams LM, Gordon E, Schofield PR, Mather K, Armstrong NJ, Wen W, Sachdev PS, Kwok JBJ. GSK3B and MAPT polymorphisms are associated with grey matter and intracranial volume in healthy individuals. PLoS One 2013; 8:e71750. [PMID: 23951236 PMCID: PMC3741177 DOI: 10.1371/journal.pone.0071750] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 07/02/2013] [Indexed: 12/12/2022] Open
Abstract
The microtubule-associated protein tau gene (MAPT) codes for a protein that plays an integral role in stabilisation of microtubules and axonal transport in neurons. As well as its role in susceptibility to neurodegeneration, previous studies have found an association between the MAPT haplotype and intracranial volume and regional grey matter volumes in healthy adults. The glycogen synthase kinase-3β gene (GSK3B) codes for a serine/threonine kinase that phosphorylates various proteins, including tau, and has also been associated with risk for neurodegenerative disorders and schizophrenia. We examined the effects of MAPT and two functional promoter polymorphisms in GSK3B (rs3755557 and rs334558) on total grey matter and intracranial volume in three independent cohorts totaling 776 neurologically healthy individuals. In vitro analyses revealed a significant effect of rs3755557 on gene expression, and altered binding of at least two transcription factors, Octamer transcription factor 1 (Oct-1) and Pre-B-cell leukemia transcription factor 1 (Pbx-1), to the GSK3B promoter. Meta-analysis across the three cohorts revealed a significant effect of rs3755557 on total grey matter volume (summary B = 0.082, 95% confidence interval = 0.037–0.128) and intracranial volume (summary B = 0.113, 95% confidence interval = 0.082–0.144). No significant effect was observed for MAPT H1/H2 diplotype or GSK3B rs334558 on total grey matter or intracranial volume. Our genetic and biochemical analyses have identified a role for GSK3B in brain development, which could have important aetiological implications for neurodegenerative and neurodevelopmental disorders.
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Affiliation(s)
- Carol Dobson-Stone
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- Department of Pathology and Inflammation and Infection Research Centre, School of Medical Sciences, University of New South Wales, Kensington, Australia
| | - Patsie Polly
- Department of Pathology and Inflammation and Infection Research Centre, School of Medical Sciences, University of New South Wales, Kensington, Australia
| | - Mayuresh S. Korgaonkar
- The Brain Dynamics Centre, University of Sydney Medical School and Westmead Millennium Institute, Westmead, Australia
| | - Leanne M. Williams
- The Brain Dynamics Centre, University of Sydney Medical School and Westmead Millennium Institute, Westmead, Australia
- Brain Resource International Database, Brain Resource Ltd., Ultimo, Sydney, New South Wales, Australia, and San Francisco, California
| | - Evian Gordon
- Brain Resource International Database, Brain Resource Ltd., Ultimo, Sydney, New South Wales, Australia, and San Francisco, California
| | - Peter R. Schofield
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- Department of Pathology and Inflammation and Infection Research Centre, School of Medical Sciences, University of New South Wales, Kensington, Australia
| | - Karen Mather
- Euroa Centre, Prince of Wales Hospital, Randwick, Australia
| | - Nicola J. Armstrong
- Cancer Program, Garvan Institute of Medical Research, Sydney, Australia, School of Mathematics and Statistics, and Prince of Wales Clinical School, University of New South Wales, Sydney, Australia
| | - Wei Wen
- Euroa Centre, Prince of Wales Hospital, Randwick, Australia
- School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Perminder S. Sachdev
- Euroa Centre, Prince of Wales Hospital, Randwick, Australia
- School of Psychiatry, University of New South Wales, Sydney, Australia
| | - John B. J. Kwok
- Neuroscience Research Australia, Randwick, New South Wales, Australia
- Department of Pathology and Inflammation and Infection Research Centre, School of Medical Sciences, University of New South Wales, Kensington, Australia
- * E-mail:
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Wong PCM, Chandrasekaran B, Zheng J. The derived allele of ASPM is associated with lexical tone perception. PLoS One 2012; 7:e34243. [PMID: 22529908 PMCID: PMC3328485 DOI: 10.1371/journal.pone.0034243] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Accepted: 02/24/2012] [Indexed: 01/12/2023] Open
Abstract
The ASPM and MCPH1 genes have been implicated in the adaptive evolution of the human brain [Mekel-Bobrov N. et al., 2005. Ongoing adaptive evolution of ASPM, a brain size determinant in homo sapiens. Science 309; Evans P.D. et al., 2005. Microcephalin, a gene regulating brain size, continues to evolve adaptively in humans. Science 309]. Curiously, experimental attempts have failed to connect the implicated SNPs in these genes with higher-level brain functions. These results stand in contrast with a population-level study linking the population frequency of their alleles with the tendency to use lexical tones in a language [Dediu D., Ladd D.R., 2007. Linguistic tone is related to the population frequency of the adaptive haplogroups of two brain size genes, ASPM and microcephalin. Proc. Natl. Acad. Sci. U.S.A. 104]. In the present study, we found a significant correlation between the load of the derived alleles of ASPM and tone perception in a group of European Americans who did not speak a tone language. Moreover, preliminary results showed a significant correlation between ASPM load and hemodynamic responses to lexical tones in the auditory cortex, and such correlation remained after phonemic awareness, auditory working memory, and non-verbal IQ were controlled. As in previous studies, no significant correlation between ASPM and cognitive measures were found. MCPH1 did not correlate with any measures. These results suggest that the association between the recently derived allele of ASPM is likely to be specific and is tied to higher level brain functions in the temporal cortex related to human communication.
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Affiliation(s)
- Patrick C M Wong
- Roxelyn and Richard Pepper Department of Communication Sciences & Disorders, Northwestern University, Evanston, Illinois, United States of America.
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Abstract
The tremendous shifts in the size, structure, and function of the brain during primate evolution are ultimately caused by changes at the genetic level. Understanding what these changes are and how they effect the phenotypic changes observed lies at the heart of understanding evolutionary change. This chapter focuses on understanding the genetic basis of primate brain evolution, considering the substrates and mechanisms through which genetic change occurs. It also discusses the implications that our current understandings and tools have for what we have already discovered and where our studies will head in the future. While genetic and genomic studies have identified many regions undergoing positive selection during primate evolution, the findings are certainly not exhaustive and functional relevance remains to be confirmed. Nevertheless, a strong foundation has been built upon which future studies will emerge.
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Affiliation(s)
- Eric J Vallender
- New England Primate Research Center, Harvard Medical School, Southborough, MA, USA.
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Abstract
Brain development in the early stages of life has been suggested to be one of the factors that may influence an individual's risk of Alzheimer disease (AD) later in life. Four microcephaly genes, which regulate brain development in utero and have been suggested to play a role in the evolution of the human brain, were selected as candidate genes that may modulate the risk of AD. We examined the association between single nucleotide polymorphisms tagging common sequence variations in these genes and risk of AD in two case-control samples. We found that the G allele of rs2442607 in microcephalin 1 was associated with an increased risk of AD (under an additive genetic model, P=0.01; odds ratio=3.41; confidence interval, 1.77-6.57). However, this association was not replicated using another case-control sample research participants from the Alzheimer Disease Neuroimaging Initiative. We conclude that the common variations we measured in the 4 microcephaly genes do not affect the risk of AD or that their effect size is small.
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Regional heterogeneity in limbic maturational changes: evidence from integrating cortical thickness, volumetric and diffusion tensor imaging measures. Neuroimage 2011; 55:868-79. [PMID: 21224000 DOI: 10.1016/j.neuroimage.2010.12.087] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Revised: 11/16/2010] [Accepted: 12/20/2010] [Indexed: 12/22/2022] Open
Abstract
Magnetic resonance imaging (MRI) studies of structural brain development have suggested that the limbic system is relatively preserved in comparison to other brain regions with healthy aging. The goal of this study was to systematically investigate age-related changes of the limbic system using measures of cortical thickness, volumetric and diffusion characteristics. We also investigated if the "relative preservation" concept is consistent across the individual sub-regions of the limbic system. T1 weighted structural MRI and Diffusion Tensor Imaging data from 476 healthy participants from the Brain Resource International Database was used for this study. Age-related changes in grey matter (GM)/white matter (WM) volume, cortical thickness, diffusional characteristics for the pericortical WM and for the fiber tracts associated with the limbic regions were quantified. A regional variability in the aging patterns across the limbic system was present. Four important patterns of age-related changes were highlighted for the limbic sub-regions: 1. early maturation of GM with late loss in the hippocampus and amygdala; 2. an extreme pattern of GM preservation in the entorhinal cortex; 3. a flat pattern of reduced GM loss in the anterior cingulate and the parahippocampus and; 4. accelerated GM loss in the isthmus and posterior cingulate. The GM volumetric data and cortical thickness measures proved to be internally consistent, while the diffusional measures provided complementary data that seem consistent with the GM trends identified. This heterogeneity can be hypothesized to be associated with age-related changes of cognitive function specialized for that region and direct connections to the other brain regions sub-serving these functions.
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Riveros C, Mellor D, Gandhi KS, McKay FC, Cox MB, Berretta R, Vaezpour SY, Inostroza-Ponta M, Broadley SA, Heard RN, Vucic S, Stewart GJ, Williams DW, Scott RJ, Lechner-Scott J, Booth DR, Moscato P. A transcription factor map as revealed by a genome-wide gene expression analysis of whole-blood mRNA transcriptome in multiple sclerosis. PLoS One 2010; 5:e14176. [PMID: 21152067 PMCID: PMC2995726 DOI: 10.1371/journal.pone.0014176] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 10/20/2010] [Indexed: 12/03/2022] Open
Abstract
Background Several lines of evidence suggest that transcription factors are involved in the pathogenesis of Multiple Sclerosis (MS) but complete mapping of the whole network has been elusive. One of the reasons is that there are several clinical subtypes of MS and transcription factors that may be involved in one subtype may not be in others. We investigate the possibility that this network could be mapped using microarray technologies and contemporary bioinformatics methods on a dataset derived from whole blood in 99 untreated MS patients (36 Relapse Remitting MS, 43 Primary Progressive MS, and 20 Secondary Progressive MS) and 45 age-matched healthy controls. Methodology/Principal Findings We have used two different analytical methodologies: a non-standard differential expression analysis and a differential co-expression analysis, which have converged on a significant number of regulatory motifs that are statistically overrepresented in genes that are either differentially expressed (or differentially co-expressed) in cases and controls (e.g., V$KROX_Q6, p-value <3.31E-6; V$CREBP1_Q2, p-value <9.93E-6, V$YY1_02, p-value <1.65E-5). Conclusions/Significance Our analysis uncovered a network of transcription factors that potentially dysregulate several genes in MS or one or more of its disease subtypes. The most significant transcription factor motifs were for the Early Growth Response EGR/KROX family, ATF2, YY1 (Yin and Yang 1), E2F-1/DP-1 and E2F-4/DP-2 heterodimers, SOX5, and CREB and ATF families. These transcription factors are involved in early T-lymphocyte specification and commitment as well as in oligodendrocyte dedifferentiation and development, both pathways that have significant biological plausibility in MS causation.
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Affiliation(s)
- Carlos Riveros
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
| | - Drew Mellor
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- School of Computer Science and Software Engineering, The University of Western Australia, Crawley, Australia
| | - Kaushal S. Gandhi
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Fiona C. McKay
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Mathew B. Cox
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- Hunter Medical Research Institute, Newcastle, Australia
| | - Regina Berretta
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
| | - S. Yahya Vaezpour
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- Department of Computer Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Mario Inostroza-Ponta
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- Departamento de Ingeniería Informática, Universidad de Santiago de Chile, Santiago, Chile
| | - Simon A. Broadley
- School of Medicine, Griffith University, Brisbane, Australia
- Department of Neurology, Gold Coast Hospital, Southport, Australia
| | - Robert N. Heard
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Stephen Vucic
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Graeme J. Stewart
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | | | - Rodney J. Scott
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
| | - Jeanette Lechner-Scott
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
| | - David R. Booth
- Westmead Millennium Institute, University of Sydney, Westmead, Australia
| | - Pablo Moscato
- Centre for Bioinformatics, Biomarker Discovery & Information-Based Medicine, University of Newcastle, and Hunter Medical Research Institute, Newcastle, Australia
- Australian Research Council Centre of Excellence in Bioinformatics, St Lucia, Australia
- * E-mail:
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Abstract
The role of microcephaly genes in normal variation in human brain size has been controversial. New studies show that a link does exist and imply sex-specificity in microcephaly gene action during neurogenesis.
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Sex-dependent association of common variants of microcephaly genes with brain structure. Proc Natl Acad Sci U S A 2009; 107:384-8. [PMID: 20080800 DOI: 10.1073/pnas.0908454107] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Loss-of-function mutations in the genes associated with primary microcephaly (MCPH) reduce human brain size by about two-thirds, without producing gross abnormalities in brain organization or physiology and leaving other organs largely unaffected [Woods CG, et al. (2005) Am J Hum Genet 76:717-728]. There is also evidence suggesting that MCPH genes have evolved rapidly in primates and humans and have been subjected to selection in recent human evolution [Vallender EJ, et al. (2008) Trends Neurosci 31:637-644]. Here, we show that common variants of MCPH genes account for some of the common variation in brain structure in humans, independently of disease status. We investigated the correlations of SNPs from four MCPH genes with brain morphometry phenotypes obtained with MRI. We found significant, sex-specific associations between common, nonexonic, SNPs of the genes CDK5RAP2, MCPH1, and ASPM, with brain volume or cortical surface area in an ethnically homogenous Norwegian discovery sample (n = 287), including patients with mental illness. The most strongly associated SNP findings were replicated in an independent North American sample (n = 656), which included patients with dementia. These results are consistent with the view that common variation in brain structure is associated with genetic variants located in nonexonic, presumably regulatory, regions.
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Thornton GK, Woods CG. Primary microcephaly: do all roads lead to Rome? Trends Genet 2009; 25:501-10. [PMID: 19850369 PMCID: PMC2816178 DOI: 10.1016/j.tig.2009.09.011] [Citation(s) in RCA: 300] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 09/24/2009] [Accepted: 09/24/2009] [Indexed: 02/06/2023]
Abstract
The relatively large brain and expanded cerebral cortex of humans is unusual in the animal kingdom and is thought to have promoted our adaptability and success as a species. One approach for investigating neurogenesis is the study of autosomal recessive primary microcephaly (MCPH), in which prenatal brain growth is significantly reduced without an effect on brain structure. To date, eight MCPH loci and five genes have been identified. Unexpectedly, all MCPH proteins are ubiquitous and localise to centrosomes for at least part of the cell cycle. Here, we focus on recent functional studies of MCPH proteins that reveal the centrosome as a final integration point for many regulatory pathways affecting prenatal neurogenesis in mammals.
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Affiliation(s)
- Gemma K Thornton
- Department of Medical Genetics, Cambridge Institute for Medical Research, Wellcome/MRC Building, Addenbrookes Hospital, Cambridge, UK
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17
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Maghirang-Rodriguez R, Archie JG, Schwartz CE, Collins JS. The c.940G variant of the Microcephalin (MCPH1) gene is not associated with microcephaly or mental retardation. Am J Med Genet A 2009; 149A:622-5. [PMID: 19267414 DOI: 10.1002/ajmg.a.32721] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
It was reported that positive selection has acted upon a gene involved in autosomal recessive primary microcephaly, Microcephalin (MCPH1/BRIT1), located at chromosome 8p23. We tested if the reported diagnostic single nucleotide polymorphism (SNP) (G37995C or c.940G > C) of a derived haplogroup of the MCPH1 gene had significantly different frequencies in mental retardation (MR) patients and in MR patients with microcephaly as compared to MR patients without microcephaly and controls in African-American and Caucasian populations in South Carolina, US. Our results suggest that there is little or no association between the MCPH1 c.940G allele and either microcephaly or MR. However, we found highly significant racial differences in the c.940G > C SNP allele frequencies between African-American and Caucasian populations.
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Affiliation(s)
- Reycel Maghirang-Rodriguez
- JC Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, South Carolina 29646, USA
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18
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Abstract
We review the literature on the relation between whole brain size and general mental ability (GMA) both within and between species. Among humans, in 28 samples using brain imaging techniques, the mean brain size/GMA correlation is 0.40 (N = 1,389; p < 10−10); in 59 samples using external head size measures it is 0.20 (N = 63,405; p < 10−10). In 6 samples using the method of correlated vectors to distill g, the general factor of mental ability, the mean r is 0.63. We also describe the brain size/GMA correlations with age, socioeconomic position, sex, and ancestral population groups, which also provide information about brain–behavior relationships. Finally, we examine brain size and mental ability from an evolutionary and behavior genetic perspective.
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Affiliation(s)
- J Philippe Rushton
- Departments of Psychology and Biology, University of Western Ontario, London, Ontario, Canada.
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Vallender EJ. Exploring the origins of the human brain through molecular evolution. BRAIN, BEHAVIOR AND EVOLUTION 2008; 72:168-77. [PMID: 18836262 DOI: 10.1159/000151476] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The emergence of the human brain is one of evolution's most compelling mysteries. With its singular importance and astounding complexity, understanding the forces that gave rise to the human brain is a major undertaking. Recently, the identification and publication of the complete genomic sequence of humans, mice, chimpanzees, and macaques has allowed for large-scale studies looking for the genic substrates of this natural selection. These investigations into positive selection, however, have generally produced incongruous results. Here we consider some of these studies and their differences in methodologies with an eye towards how they affect the results. We also clarify the strengths and weaknesses of each of these approaches and discuss how these can be synthesized to develop a more complete understanding of the genetic correlates behind the human brain and the selective events that have acted upon them.
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Affiliation(s)
- Eric J Vallender
- Division of Neurochemistry, New England Primate Research Center, Harvard Medical School, Southborough, MA 01772, USA.
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Ali F, Meier R. Positive Selection in ASPM Is Correlated with Cerebral Cortex Evolution across Primates but Not with Whole-Brain Size. Mol Biol Evol 2008; 25:2247-50. [PMID: 18718919 DOI: 10.1093/molbev/msn184] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Farhan Ali
- Department of Psychology, National University of Singapore, Singapore
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