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Abstract
Some of the genes responsible for the evolution of light skin pigmentation in Europeans show signals of positive selection in present-day populations. Recently, genome-wide association studies have highlighted the highly polygenic nature of skin pigmentation. It is unclear whether selection has operated on all of these genetic variants or just a subset. By studying variation in over a thousand ancient genomes from West Eurasia covering 40,000 y, we are able to study both the aggregate behavior of pigmentation-associated variants and the evolutionary history of individual variants. We find that the evolution of light skin pigmentation in Europeans was driven by frequency changes in a relatively small fraction of the genetic variants that are associated with variation in the trait today. Skin pigmentation is a classic example of a polygenic trait that has experienced directional selection in humans. Genome-wide association studies have identified well over a hundred pigmentation-associated loci, and genomic scans in present-day and ancient populations have identified selective sweeps for a small number of light pigmentation-associated alleles in Europeans. It is unclear whether selection has operated on all of the genetic variation associated with skin pigmentation as opposed to just a small number of large-effect variants. Here, we address this question using ancient DNA from 1,158 individuals from West Eurasia covering a period of 40,000 y combined with genome-wide association summary statistics from the UK Biobank. We find a robust signal of directional selection in ancient West Eurasians on 170 skin pigmentation-associated variants ascertained in the UK Biobank. However, we also show that this signal is driven by a limited number of large-effect variants. Consistent with this observation, we find that a polygenic selection test in present-day populations fails to detect selection with the full set of variants. Our data allow us to disentangle the effects of admixture and selection. Most notably, a large-effect variant at SLC24A5 was introduced to Western Europe by migrations of Neolithic farming populations but continued to be under selection post-admixture. This study shows that the response to selection for light skin pigmentation in West Eurasia was driven by a relatively small proportion of the variants that are associated with present-day phenotypic variation.
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Werren EA, Garcia O, Bigham AW. Identifying adaptive alleles in the human genome: from selection mapping to functional validation. Hum Genet 2020; 140:241-276. [PMID: 32728809 DOI: 10.1007/s00439-020-02206-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 07/07/2020] [Indexed: 12/19/2022]
Abstract
The suite of phenotypic diversity across geographically distributed human populations is the outcome of genetic drift, gene flow, and natural selection throughout human evolution. Human genetic variation underlying local biological adaptations to selective pressures is incompletely characterized. With the emergence of population genetics modeling of large-scale genomic data derived from diverse populations, scientists are able to map signatures of natural selection in the genome in a process known as selection mapping. Inferred selection signals further can be used to identify candidate functional alleles that underlie putative adaptive phenotypes. Phenotypic association, fine mapping, and functional experiments facilitate the identification of candidate adaptive alleles. Functional investigation of candidate adaptive variation using novel techniques in molecular biology is slowly beginning to unravel how selection signals translate to changes in biology that underlie the phenotypic spectrum of our species. In addition to informing evolutionary hypotheses of adaptation, the discovery and functional annotation of adaptive alleles also may be of clinical significance. While selection mapping efforts in non-European populations are growing, there remains a stark under-representation of diverse human populations in current public genomic databases, of both clinical and non-clinical cohorts. This lack of inclusion limits the study of human biological variation. Identifying and functionally validating candidate adaptive alleles in more global populations is necessary for understanding basic human biology and human disease.
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Affiliation(s)
- Elizabeth A Werren
- Department of Human Genetics, The University of Michigan, Ann Arbor, MI, USA
- Department of Anthropology, The University of Michigan, Ann Arbor, MI, USA
| | - Obed Garcia
- Department of Anthropology, The University of Michigan, Ann Arbor, MI, USA
| | - Abigail W Bigham
- Department of Anthropology, University of California Los Angeles, 341 Haines Hall, Los Angeles, CA, 90095, USA.
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Ombra MN, Paliogiannis P, Doneddu V, Sini MC, Colombino M, Rozzo C, Stanganelli I, Tanda F, Cossu A, Palmieri G. Vitamin D status and risk for malignant cutaneous melanoma: recent advances. Eur J Cancer Prev 2017; 26:532-541. [PMID: 28125434 PMCID: PMC5627529 DOI: 10.1097/cej.0000000000000334] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 12/07/2016] [Indexed: 01/08/2023]
Abstract
Cutaneous malignant melanoma, whose incidence is increasing steadily worldwide, is the result of complex interactions between individual genetic factors and environmental risk factors. Ultraviolet radiation represents the most important environmental risk factor for the development of skin cancers, including melanoma. Sun exposure and early sunburn during childhood are the principal causes of cutaneous melanoma insurgence in adults, with double the risk relative to a nonexposed population. Consequently, ultraviolet protection has long been recognized as an important measure to prevent such a malignancy. Biological and epidemiological data suggest that vitamin D status could affect the risk of cancer and play a role in cancer prevention by exerting antiproliferative effects. Solar radiations are critical for vitamin D synthesis in humans; however, uncontrolled and intensive sun exposure is dangerous to skin health and may contribute toward the development of cutaneous malignant melanoma. An optimum balance between sun protection and exposure is thus advocated. Additional research is required to confirm the preventive role of vitamin D in melanoma incidence or a positive influence on patient outcome.
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Affiliation(s)
- Maria N. Ombra
- Institute of Food Sciences, National Research Council (CNR), Avellino
| | | | - Valentina Doneddu
- Department of Surgical, Microsurgical and Medical Sciences, University of Sassari
| | - Maria C. Sini
- Institute of Biomolecular Chemistry, National Research Council (CNR), Cancer Genetics Unit, Sassari
| | - Maria Colombino
- Institute of Biomolecular Chemistry, National Research Council (CNR), Cancer Genetics Unit, Sassari
| | - Carla Rozzo
- Institute of Biomolecular Chemistry, National Research Council (CNR), Cancer Genetics Unit, Sassari
| | - Ignazio Stanganelli
- Romagna Scientific Institute for the Study and Cure of Tumors, Skin Cancer Unit, Meldola, Italy
| | - Francesco Tanda
- Department of Surgical, Microsurgical and Medical Sciences, University of Sassari
| | - Antonio Cossu
- Department of Surgical, Microsurgical and Medical Sciences, University of Sassari
| | - Giuseppe Palmieri
- Institute of Biomolecular Chemistry, National Research Council (CNR), Cancer Genetics Unit, Sassari
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Jablonski NG, Chaplin G. The colours of humanity: the evolution of pigmentation in the human lineage. Philos Trans R Soc Lond B Biol Sci 2017; 372:20160349. [PMID: 28533464 PMCID: PMC5444068 DOI: 10.1098/rstb.2016.0349] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/09/2016] [Indexed: 12/16/2022] Open
Abstract
Humans are a colourful species of primate, with human skin, hair and eye coloration having been influenced by a great variety of evolutionary forces throughout prehistory. Functionally naked skin has been the physical interface between the physical environment and the human body for most of the history of the genus Homo, and hence skin coloration has been under intense natural selection. From an original condition of protective, dark, eumelanin-enriched coloration in early tropical-dwelling Homo and Homo sapiens, loss of melanin pigmentation occurred under natural selection as Homo sapiens dispersed into non-tropical latitudes of Africa and Eurasia. Genes responsible for skin, hair and eye coloration appear to have been affected significantly by population bottlenecks in the course of Homo sapiens dispersals. Because specific skin colour phenotypes can be created by different combinations of skin colour-associated genetic markers, loss of genetic variability due to genetic drift appears to have had negligible effects on the highly redundant genetic 'palette' for the skin colour. This does not appear to have been the case for hair and eye coloration, however, and these traits appear to have been more strongly influenced by genetic drift and, possibly, sexual selection.This article is part of the themed issue 'Animal coloration: production, perception, function and application'.
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Affiliation(s)
- Nina G Jablonski
- Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, USA
| | - George Chaplin
- Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, USA
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López S, García I, Smith I, Sevilla A, Izagirre N, de la Rúa C, Alonso S. Discovery of copy number variants by multiplex amplifiable probe hybridization (MAPH) in candidate pigmentation genes. Ann Hum Biol 2015; 42:485-93. [DOI: 10.3109/03014460.2014.965202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Wollstein A, Lao O. Detecting individual ancestry in the human genome. INVESTIGATIVE GENETICS 2015; 6:7. [PMID: 25937887 PMCID: PMC4416275 DOI: 10.1186/s13323-015-0019-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 01/12/2015] [Indexed: 01/26/2023]
Abstract
Detecting and quantifying the population substructure present in a sample of individuals are of main interest in the fields of genetic epidemiology, population genetics, and forensics among others. To date, several algorithms have been proposed for estimating the amount of genetic ancestry within an individual. In the present review, we introduce the most widely used methods in population genetics for detecting individual genetic ancestry. We further show, by means of simulations, the performance of popular algorithms for detecting individual ancestry in various controlled demographic scenarios. Finally, we provide some hints on how to interpret the results from these algorithms.
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Affiliation(s)
- Andreas Wollstein
- Department of Forensic Molecular Biology, Erasmus MC University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands ; Section of Evolutionary Biology, Department of Biology II, University of Munich, 82152 Planegg-Martinsried, Germany
| | - Oscar Lao
- Department of Forensic Molecular Biology, Erasmus MC University Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands ; Current address: Centro Nacional de Análisis Genómico, Baldiri Reixac, 4, Barcleona Science Park - Tower I, 08028 Barcelona, Spain
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López S, García Ó, Yurrebaso I, Flores C, Acosta-Herrera M, Chen H, Gardeazabal J, Careaga JM, Boyano MD, Sánchez A, Ratón-Nieto JA, Sevilla A, Smith-Zubiaga I, de Galdeano AG, Martinez-Cadenas C, Izagirre N, de la Rúa C, Alonso S. The interplay between natural selection and susceptibility to melanoma on allele 374F of SLC45A2 gene in a South European population. PLoS One 2014; 9:e104367. [PMID: 25093503 PMCID: PMC4122405 DOI: 10.1371/journal.pone.0104367] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 07/08/2014] [Indexed: 11/18/2022] Open
Abstract
We aimed to study the selective pressures interacting on SLC45A2 to investigate the interplay between selection and susceptibility to disease. Thus, we enrolled 500 volunteers from a geographically limited population (Basques from the North of Spain) and by resequencing the whole coding region and intron 5 of the 34 most and the 34 least pigmented individuals according to the reflectance distribution, we observed that the polymorphism Leu374Phe (L374F, rs16891982) was statistically associated with skin color variability within this sample. In particular, allele 374F was significantly more frequent among the individuals with lighter skin. Further genotyping an independent set of 558 individuals of a geographically wider population with known ancestry in the Spanish population also revealed that the frequency of L374F was significantly correlated with the incident UV radiation intensity. Selection tests suggest that allele 374F is being positively selected in South Europeans, thus indicating that depigmentation is an adaptive process. Interestingly, by genotyping 119 melanoma samples, we show that this variant is also associated with an increased susceptibility to melanoma in our populations. The ultimate driving force for this adaptation is unknown, but it is compatible with the vitamin D hypothesis. This shows that molecular evolution analysis can be used as a useful technology to predict phenotypic and biomedical consequences in humans.
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Affiliation(s)
- Saioa López
- Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | - Óscar García
- Ertzaintza Forensic Unit, Erandio, Bizkaia, Spain
| | | | - Carlos Flores
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
- Research Unit, Hospital Universitario N.S. de Candelaria, Tenerife, Spain
- Applied Genomics Group (G2A), Genetics Laboratory, Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias, Universidad de La Laguna, Tenerife, Spain
| | - Marialbert Acosta-Herrera
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
- Research Unit, Hospital Universitario N.S. de Candelaria, Tenerife, Spain
- Research Unit, Universitary Hospital Dr. Negrin, Las Palmas de Gran Canaria, Spain
| | - Hua Chen
- Center for Computational Genetics and Genomics, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Jesús Gardeazabal
- Dermatology Service, BioCruces Health Research Institute, Cruces University Hospital, Cruces-Barakaldo, Bizkaia, Spain
| | - Jesús María Careaga
- Dermatology Service, BioCruces Health Research Institute, Basurto University Hospital, Bilbao, Bizkaia, Spain
| | - María Dolores Boyano
- Department of Cell Biology and Histology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | - Ana Sánchez
- Dermatology Service, BioCruces Health Research Institute, Basurto University Hospital, Bilbao, Bizkaia, Spain
| | - Juan Antonio Ratón-Nieto
- Dermatology Service, BioCruces Health Research Institute, Cruces University Hospital, Cruces-Barakaldo, Bizkaia, Spain
| | - Arrate Sevilla
- Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | - Isabel Smith-Zubiaga
- Department of Zoology and Animal Cell Biology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | - Alicia García de Galdeano
- Department of Cell Biology and Histology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | | | - Neskuts Izagirre
- Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | - Concepción de la Rúa
- Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
| | - Santos Alonso
- Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain
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Advances in Human Biology: Combining Genetics and Molecular Biophysics to Pave the Way for Personalized Diagnostics and Medicine. ACTA ACUST UNITED AC 2014. [DOI: 10.1155/2014/471836] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Advances in several biology-oriented initiatives such as genome sequencing and structural genomics, along with the progress made through traditional biological and biochemical research, have opened up a unique opportunity to better understand the molecular effects of human diseases. Human DNA can vary significantly from person to person and determines an individual’s physical characteristics and their susceptibility to diseases. Armed with an individual’s DNA sequence, researchers and physicians can check for defects known to be associated with certain diseases by utilizing various databases. However, for unclassified DNA mutations or in order to reveal molecular mechanism behind the effects, the mutations have to be mapped onto the corresponding networks and macromolecular structures and then analyzed to reveal their effect on the wild type properties of biological processes involved. Predicting the effect of DNA mutations on individual’s health is typically referred to as personalized or companion diagnostics. Furthermore, once the molecular mechanism of the mutations is revealed, the patient should be given drugs which are the most appropriate for the individual genome, referred to as pharmacogenomics. Altogether, the shift in focus in medicine towards more genomic-oriented practices is the foundation of personalized medicine. The progress made in these rapidly developing fields is outlined.
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Basu Mallick C, Iliescu FM, Möls M, Hill S, Tamang R, Chaubey G, Goto R, Ho SYW, Gallego Romero I, Crivellaro F, Hudjashov G, Rai N, Metspalu M, Mascie-Taylor CGN, Pitchappan R, Singh L, Mirazon-Lahr M, Thangaraj K, Villems R, Kivisild T. The light skin allele of SLC24A5 in South Asians and Europeans shares identity by descent. PLoS Genet 2013; 9:e1003912. [PMID: 24244186 PMCID: PMC3820762 DOI: 10.1371/journal.pgen.1003912] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 09/07/2013] [Indexed: 11/18/2022] Open
Abstract
Skin pigmentation is one of the most variable phenotypic traits in humans. A non-synonymous substitution (rs1426654) in the third exon of SLC24A5 accounts for lighter skin in Europeans but not in East Asians. A previous genome-wide association study carried out in a heterogeneous sample of UK immigrants of South Asian descent suggested that this gene also contributes significantly to skin pigmentation variation among South Asians. In the present study, we have quantitatively assessed skin pigmentation for a largely homogeneous cohort of 1228 individuals from the Southern region of the Indian subcontinent. Our data confirm significant association of rs1426654 SNP with skin pigmentation, explaining about 27% of total phenotypic variation in the cohort studied. Our extensive survey of the polymorphism in 1573 individuals from 54 ethnic populations across the Indian subcontinent reveals wide presence of the derived-A allele, although the frequencies vary substantially among populations. We also show that the geospatial pattern of this allele is complex, but most importantly, reflects strong influence of language, geography and demographic history of the populations. Sequencing 11.74 kb of SLC24A5 in 95 individuals worldwide reveals that the rs1426654-A alleles in South Asian and West Eurasian populations are monophyletic and occur on the background of a common haplotype that is characterized by low genetic diversity. We date the coalescence of the light skin associated allele at 22–28 KYA. Both our sequence and genome-wide genotype data confirm that this gene has been a target for positive selection among Europeans. However, the latter also shows additional evidence of selection in populations of the Middle East, Central Asia, Pakistan and North India but not in South India. Human skin color is one of the most visible aspects of human diversity. The genetic basis of pigmentation in Europeans has been understood to some extent, but our knowledge about South Asians has been restricted to a handful of studies. It has been suggested that a single nucleotide difference in SLC24A5 accounts for 25–38% European-African pigmentation differences and correlates with lighter skin. This genetic variant has also been associated with skin color variation among South Asians living in the UK. Here, we report a study based on a homogenous cohort of South India. Our results confirm that SLC24A5 plays a key role in pigmentation diversity of South Asians. Country-wide screening of the variant reveals that the light skin associated allele is widespread in the Indian subcontinent and its complex patterning is shaped by a combination of processes involving selection and demographic history of the populations. By studying the variation of SLC24A5 sequences among a diverse set of individuals, we show that the light skin associated allele in South Asians is identical by descent to that found in Europeans. Our study also provides new insights into positive selection acting on the gene and the evolutionary history of light skin in humans.
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Affiliation(s)
- Chandana Basu Mallick
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- Estonian Biocentre, Tartu, Estonia
- * E-mail: (CBM); (TK)
| | - Florin Mircea Iliescu
- Division of Biological Anthropology, University of Cambridge, Cambridge, United Kingdom
| | - Märt Möls
- Estonian Biocentre, Tartu, Estonia
- Institute of Mathematical Statistics, University of Tartu, Tartu, Estonia
| | - Sarah Hill
- Division of Biological Anthropology, University of Cambridge, Cambridge, United Kingdom
| | - Rakesh Tamang
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | - Rie Goto
- Division of Biological Anthropology, University of Cambridge, Cambridge, United Kingdom
| | - Simon Y. W. Ho
- School of Biological Sciences, University of Sydney, Sydney, Australia
| | - Irene Gallego Romero
- Division of Biological Anthropology, University of Cambridge, Cambridge, United Kingdom
| | - Federica Crivellaro
- Leverhulme Centre for Human Evolutionary Studies, University of Cambridge, Cambridge, United Kingdom
| | - Georgi Hudjashov
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- Estonian Biocentre, Tartu, Estonia
| | - Niraj Rai
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Mait Metspalu
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- Estonian Biocentre, Tartu, Estonia
| | | | - Ramasamy Pitchappan
- Chettinad Academy of Research and Education, Chettinad Health City, Chennai, India
| | - Lalji Singh
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
- Banaras Hindu University, Varanasi, India
| | - Marta Mirazon-Lahr
- Leverhulme Centre for Human Evolutionary Studies, University of Cambridge, Cambridge, United Kingdom
| | | | - Richard Villems
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- Estonian Biocentre, Tartu, Estonia
- Estonian Academy of Sciences, Tallinn, Estonia
| | - Toomas Kivisild
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- Estonian Biocentre, Tartu, Estonia
- Division of Biological Anthropology, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (CBM); (TK)
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Hudjashov G, Villems R, Kivisild T. Global patterns of diversity and selection in human tyrosinase gene. PLoS One 2013; 8:e74307. [PMID: 24040225 PMCID: PMC3770694 DOI: 10.1371/journal.pone.0074307] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 07/31/2013] [Indexed: 01/09/2023] Open
Abstract
Global variation in skin pigmentation is one of the most striking examples of environmental adaptation in humans. More than two hundred loci have been identified as candidate genes in model organisms and a few tens of these have been found to be significantly associated with human skin pigmentation in genome-wide association studies. However, the evolutionary history of different pigmentation genes is rather complex: some loci have been subjected to strong positive selection, while others evolved under the relaxation of functional constraints in low UV environment. Here we report the results of a global study of the human tyrosinase gene, which is one of the key enzymes in melanin production, to assess the role of its variation in the evolution of skin pigmentation differences among human populations. We observe a higher rate of non-synonymous polymorphisms in the European sample consistent with the relaxation of selective constraints. A similar pattern was previously observed in the MC1R gene and concurs with UV radiation-driven model of skin color evolution by which mutations leading to lower melanin levels and decreased photoprotection are subject to purifying selection at low latitudes while being tolerated or even favored at higher latitudes because they facilitate UV-dependent vitamin D production. Our coalescent date estimates suggest that the non-synonymous variants, which are frequent in Europe and North Africa, are recent and have emerged after the separation of East and West Eurasian populations.
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Affiliation(s)
- Georgi Hudjashov
- Evolutionary Biology Group, Estonian Biocentre, Tartu, Estonia
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- * E-mail:
| | - Richard Villems
- Evolutionary Biology Group, Estonian Biocentre, Tartu, Estonia
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- Estonian Academy of Sciences, Tallinn, Estonia
| | - Toomas Kivisild
- Evolutionary Biology Group, Estonian Biocentre, Tartu, Estonia
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- Division of Biological Anthropology, University of Cambridge, Cambridge, United Kingdom
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11
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Abstract
Genome-wide association studies and comparative genomics have established major loci and specific polymorphisms affecting human skin, hair and eye color. Environmental changes have had an impact on selected pigmentation genes as populations have expanded into different regions of the globe.
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Affiliation(s)
- Richard A Sturm
- Institute for Molecular Bioscience, Melanogenix Group, The University of Queensland, Brisbane, Qld 4072, Australia.
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