1
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Pu Y, Pu S, Chen Y, Kong Q, Liu X, Zhao Q, Xu K, Liu J, Li M, Xu X, Qiao X, Su B, Chen J, Yang Z. Weakened tanning ability is an important mechanism for evolutionary skin lightening in East Asians. J Genet Genomics 2024; 51:703-713. [PMID: 38461943 DOI: 10.1016/j.jgg.2024.03.001] [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: 02/28/2024] [Revised: 03/03/2024] [Accepted: 03/03/2024] [Indexed: 03/12/2024]
Abstract
The evolution of light-skin pigmentation among Eurasians is considered as an adaptation to the high-latitude environments. East Asians are ideal populations for studying skin color evolution because of the complex environment of East Asia. Here, we report a strong selection signal for the pigmentation gene phenylalanine hydroxylase (PAH) in light-skinned Han Chinese individuals. The intron mutation rs10778203 in PAH is enriched in East Asians and is significantly associated with skin color of the back of the hand in Han Chinese males (P < 0.05). In vitro luciferase and transcription factor binding assays show that the ancestral allele of rs10778203 could bind to SMAD2 and has a significant enhancer activity for PAH. However, the derived T allele (the major allele in East Asians) of rs10778203 decreases the binding activity of transcription factors and enhancer activity. Meanwhile, the derived T allele of rs10778203 shows a weaker ultraviolet radiation response in A375 cells and zebrafish embryos. Furthermore, rs10778203 decreases melanin production in transgenic zebrafish embryos after ultraviolet B (UVB) treatment. Collectively, PAH is a potential pigmentation gene that regulates skin tanning ability. Natural selection has enriched the adaptive allele, resulting in weakened tanning ability in East Asians, suggesting a unique genetic mechanism for evolutionary skin lightening in East Asians.
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Affiliation(s)
- Youwei Pu
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Siyu Pu
- Department of Pediatric Surgery and Laboratory of Pediatric Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Yanyan Chen
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Qinghong Kong
- Guizhou Provincial College-based Key Lab for Tumor Prevention and Treatment with Distinctive Medicines, Zunyi Medical University, Zunyi, Guizhou 563000, China
| | - Xuyang Liu
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Qi Zhao
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, Yunnan 650500, China
| | - Ke Xu
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Jiuming Liu
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Mengyuan Li
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Xiaoyu Xu
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Xiaoyang Qiao
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Bing Su
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Jing Chen
- Department of Pediatric Surgery and Laboratory of Pediatric Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China.
| | - Zhaohui Yang
- Tianjian Laboratory of Advanced Biomedical Sciences, Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan 450052, China.
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2
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Fine AG, Steinrücken M. A novel expectation-maximization approach to infer general diploid selection from time-series genetic data. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.10.593575. [PMID: 38798346 PMCID: PMC11118272 DOI: 10.1101/2024.05.10.593575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Detecting and quantifying the strength of selection is a main objective in population genetics. Since selection acts over multiple generations, many approaches have been developed to detect and quantify selection using genetic data sampled at multiple points in time. Such time series genetic data is commonly analyzed using Hidden Markov Models, but in most cases, under the assumption of additive selection. However, many examples of genetic variation exhibiting non-additive mechanisms exist, making it critical to develop methods that can characterize selection in more general scenarios. Thus, we extend a previously introduced expectation-maximization algorithm for the inference of additive selection coefficients to the case of general diploid selection, in which heterozygote and homozygote fitnesses are parameterized independently. We furthermore introduce a framework to identify bespoke modes of diploid selection from given data, as well as a procedure for aggregating data across linked loci to increase power and robustness. Using extensive simulation studies, we find that our method accurately and efficiently estimates selection coefficients for different modes of diploid selection across a wide range of scenarios; however, power to classify the mode of selection is low unless selection is very strong. We apply our method to ancient DNA samples from Great Britain in the last 4,450 years, and detect evidence for selection in six genomic regions, including the well-characterized LCT locus. Our work is the first genome-wide scan characterizing signals of general diploid selection.
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Affiliation(s)
- Adam G Fine
- Department of Ecology and Evolution, University of Chicago
- Graduate Program in Biophysical Sciences, University of Chicago
| | - Matthias Steinrücken
- Department of Ecology and Evolution, University of Chicago
- Department of Human Genetics, University of Chicago
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3
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Riley R, Mathieson I, Mathieson S. INTERPRETING GENERATIVE ADVERSARIAL NETWORKS TO INFER NATURAL SELECTION FROM GENETIC DATA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.07.531546. [PMID: 36945387 PMCID: PMC10028936 DOI: 10.1101/2023.03.07.531546] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/10/2023]
Abstract
Understanding natural selection in humans and other species is a major focus for the use of machine learning in population genetics. Existing methods rely on computationally intensive simulated training data. Unlike efficient neutral coalescent simulations for demographic inference, realistic simulations of selection typically requires slow forward simulations. Because there are many possible modes of selection, a high dimensional parameter space must be explored, with no guarantee that the simulated models are close to the real processes. Mismatches between simulated training data and real test data can lead to incorrect inference. Finally, it is difficult to interpret trained neural networks, leading to a lack of understanding about what features contribute to classification. Here we develop a new approach to detect selection that requires relatively few selection simulations during training. We use a Generative Adversarial Network (GAN) trained to simulate realistic neutral data. The resulting GAN consists of a generator (fitted demographic model) and a discriminator (convolutional neural network). For a genomic region, the discriminator predicts whether it is "real" or "fake" in the sense that it could have been simulated by the generator. As the "real" training data includes regions that experienced selection and the generator cannot produce such regions, regions with a high probability of being real are likely to have experienced selection. To further incentivize this behavior, we "fine-tune" the discriminator with a small number of selection simulations. We show that this approach has high power to detect selection in simulations, and that it finds regions under selection identified by state-of-the art population genetic methods in three human populations. Finally, we show how to interpret the trained networks by clustering hidden units of the discriminator based on their correlation patterns with known summary statistics. In summary, our approach is a novel, efficient, and powerful way to use machine learning to detect natural selection.
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Affiliation(s)
- Rebecca Riley
- Department of Computer Science, Haverford College, Haverford PA, 19041 USA
| | - Iain Mathieson
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA, 19104 USA
| | - Sara Mathieson
- Department of Computer Science, Haverford College, Haverford PA, 19041 USA
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4
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Caro-Consuegra R, Lucas-Sánchez M, Comas D, Bosch E. Identifying signatures of positive selection in human populations from North Africa. Sci Rep 2023; 13:8166. [PMID: 37210386 DOI: 10.1038/s41598-023-35312-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 05/16/2023] [Indexed: 05/22/2023] Open
Abstract
Because of its location, North Africa (NA) has witnessed continuous demographic movements with an impact on the genomes of present-day human populations. Genomic data describe a complex scenario with varying proportions of at least four main ancestry components: Maghrebi, Middle Eastern-, European-, and West-and-East-African-like. However, the footprint of positive selection in NA has not been studied. Here, we compile genome-wide genotyping data from 190 North Africans and individuals from surrounding populations, investigate for signatures of positive selection using allele frequencies and linkage disequilibrium-based methods and infer ancestry proportions to discern adaptive admixture from post-admixture selection events. Our results show private candidate genes for selection in NA involved in insulin processing (KIF5A), immune function (KIF5A, IL1RN, TLR3), and haemoglobin phenotypes (BCL11A). We also detect signatures of positive selection related to skin pigmentation (SLC24A5, KITLG), and immunity function (IL1R1, CD44, JAK1) shared with European populations and candidate genes associated with haemoglobin phenotypes (HPSE2, HBE1, HBG2), other immune-related (DOCK2) traits, and insulin processing (GLIS3) traits shared with West and East African populations. Finally, the SLC8A1 gene, which codifies for a sodium-calcium exchanger, was the only candidate identified under post-admixture selection in Western NA.
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Affiliation(s)
- Rocio Caro-Consuegra
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, 08003, Barcelona, Spain
| | - Marcel Lucas-Sánchez
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, 08003, Barcelona, Spain
| | - David Comas
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, 08003, Barcelona, Spain
| | - Elena Bosch
- Institut de Biologia Evolutiva (UPF-CSIC), Departament de Medicina i Ciències de la Vida, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, 08003, Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Salud Mental, Instituto de Salud Carlos III, 28029, Madrid, Spain.
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5
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Lucock MD. The evolution of human skin pigmentation: A changing medley of vitamins, genetic variability, and UV radiation during human expansion. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023; 180:252-271. [PMID: 36790744 PMCID: PMC10083917 DOI: 10.1002/ajpa.24564] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 05/19/2022] [Accepted: 05/25/2022] [Indexed: 04/12/2023]
Abstract
This review examines putative, yet likely critical evolutionary pressures contributing to human skin pigmentation and subsequently, depigmentation phenotypes. To achieve this, it provides a synthesis of ideas that frame contemporary thinking, without limiting the narrative to pigmentation genes alone. It examines how geography and hence the quality and quantity of UV exposure, pigmentation genes, diet-related genes, vitamins, anti-oxidant nutrients, and cultural practices intersect and interact to facilitate the evolution of human skin color. The article has a strong focus on the vitamin D-folate evolutionary model, with updates on the latest biophysical research findings to support this paradigm. This model is examined within a broad canvas that takes human expansion out of Africa and genetic architecture into account. A thorough discourse on the biology of melanization is provided (includes relationship to BH4 and DNA damage repair), with the relevance of this to the UV sensitivity of folate and UV photosynthesis of vitamin D explained in detail, including the relevance of these vitamins to reproductive success. It explores whether we might be able to predict vitamin-related gene polymorphisms that pivot metabolism to the prevailing UVR exposome within the vitamin D-folate evolutionary hypothesis context. This is discussed in terms of a primary adaptive phenotype (pigmentation/depigmentation), a secondary adaptive phenotype (flexible metabolic phenotype based on vitamin-related gene polymorphism profile), and a tertiary adaptive strategy (dietary anti-oxidants to support the secondary adaptive phenotype). Finally, alternative evolutionary models for pigmentation are discussed, as are challenges to future research in this area.
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Affiliation(s)
- Mark D. Lucock
- School of Environmental & Life SciencesUniversity of NewcastleOurimbahNew South WalesAustralia
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6
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Farré X, Blay N, Cortés B, Carreras A, Iraola-Guzmán S, de Cid R. Skin Phototype and Disease: A Comprehensive Genetic Approach to Pigmentary Traits Pleiotropy Using PRS in the GCAT Cohort. Genes (Basel) 2023; 14:149. [PMID: 36672889 PMCID: PMC9859115 DOI: 10.3390/genes14010149] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/22/2022] [Accepted: 12/26/2022] [Indexed: 01/09/2023] Open
Abstract
Human pigmentation has largely been associated with different disease prevalence among populations, but most of these studies are observational and inconclusive. Known to be genetically determined, pigmentary traits have largely been studied by Genome-Wide Association Study (GWAS), mostly in Caucasian ancestry cohorts from North Europe, identifying robustly, several loci involved in many of the pigmentary traits. Here, we conduct a detailed analysis by GWAS and Polygenic Risk Score (PRS) of 13 pigmentary-related traits in a South European cohort of Caucasian ancestry (n = 20,000). We observed fair phototype strongly associated with non-melanoma skin cancer and other dermatoses and confirmed by PRS-approach the shared genetic basis with skin and eye diseases, such as melanoma (OR = 0.95), non-melanoma skin cancer (OR = 0.93), basal cell carcinoma (OR = 0.97) and darker phototype with vitiligo (OR = 1.02), cataracts (OR = 1.04). Detailed genetic analyses revealed 37 risk loci associated with 10 out of 13 analyzed traits, and 16 genes significantly associated with at least two pigmentary traits. Some of them have been widely reported, such as MC1R, HERC2, OCA2, TYR, TYRP1, SLC45A2, and some novel candidate genes C1QTNF3, LINC02876, and C1QTNF3-AMACR have not been reported in the GWAS Catalog, with regulatory potential. These results highlight the importance of the assess phototype as a genetic proxy of skin functionality and disease when evaluating open mixed populations.
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Affiliation(s)
| | | | | | | | | | - Rafael de Cid
- Genomes for Life-GCAT Lab, Germans Trias i Pujol Research Institute (IGTP), 08916 Badalona, Spain
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7
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Muktupavela RA, Petr M, Ségurel L, Korneliussen T, Novembre J, Racimo F. Modeling the spatiotemporal spread of beneficial alleles using ancient genomes. eLife 2022; 11:e73767. [PMID: 36537881 PMCID: PMC9767474 DOI: 10.7554/elife.73767] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/21/2022] [Indexed: 12/24/2022] Open
Abstract
Ancient genome sequencing technologies now provide the opportunity to study natural selection in unprecedented detail. Rather than making inferences from indirect footprints left by selection in present-day genomes, we can directly observe whether a given allele was present or absent in a particular region of the world at almost any period of human history within the last 10,000 years. Methods for studying selection using ancient genomes often rely on partitioning individuals into discrete time periods or regions of the world. However, a complete understanding of natural selection requires more nuanced statistical methods which can explicitly model allele frequency changes in a continuum across space and time. Here we introduce a method for inferring the spread of a beneficial allele across a landscape using two-dimensional partial differential equations. Unlike previous approaches, our framework can handle time-stamped ancient samples, as well as genotype likelihoods and pseudohaploid sequences from low-coverage genomes. We apply the method to a panel of published ancient West Eurasian genomes to produce dynamic maps showcasing the inferred spread of candidate beneficial alleles over time and space. We also provide estimates for the strength of selection and diffusion rate for each of these alleles. Finally, we highlight possible avenues of improvement for accurately tracing the spread of beneficial alleles in more complex scenarios.
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Affiliation(s)
- Rasa A Muktupavela
- Lundbeck GeoGenetics Centre, GLOBE Institute, Faculty of HealthCopenhagenDenmark
| | - Martin Petr
- Lundbeck GeoGenetics Centre, GLOBE Institute, Faculty of HealthCopenhagenDenmark
| | - Laure Ségurel
- UMR5558 Biométrie et Biologie Evolutive, CNRS - Université Lyon 1VilleurbanneFrance
| | | | - John Novembre
- Department of Human Genetics, University of ChicagoChicagoUnited States
| | - Fernando Racimo
- Lundbeck GeoGenetics Centre, GLOBE Institute, Faculty of HealthCopenhagenDenmark
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8
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Abstract
Strong ultraviolet (UV) radiation at high altitude imposes a serious selective pressure, which may induce skin pigmentation adaptation of indigenous populations. We conducted skin pigmentation phenotyping and genome-wide analysis of Tibetans in order to understand the underlying mechanism of adaptation to UV radiation. We observe that Tibetans have darker baseline skin color compared with lowland Han Chinese, as well as an improved tanning ability, suggesting a two-level adaptation to boost their melanin production. A genome-wide search for the responsible genes identifies GNPAT showing strong signals of positive selection in Tibetans. An enhancer mutation (rs75356281) located in GNPAT intron 2 is enriched in Tibetans (58%) but rare in other world populations (0 to 18%). The adaptive allele of rs75356281 is associated with darker skin in Tibetans and, under UVB treatment, it displays higher enhancer activities compared with the wild-type allele in in vitro luciferase assays. Transcriptome analyses of gene-edited cells clearly show that with UVB treatment, the adaptive variant of GNPAT promotes melanin synthesis, likely through the interactions of CAT and ACAA1 in peroxisomes with other pigmentation genes, and they act synergistically, leading to an improved tanning ability in Tibetans for UV protection.
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9
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Novembre J. The background and legacy of Lewontin's apportionment of human genetic diversity. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200406. [PMID: 35430890 PMCID: PMC9014184 DOI: 10.1098/rstb.2020.0406] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Lewontin's 1972 article ‘The apportionment of human diversity’ described a key feature of human genetic diversity that would have profound impacts on conversations regarding genetics and race: the typical genetic locus varies much less between classical human race groupings than one might infer from inspecting the features historically used to define those races, like skin pigmentation. From this, Lewontin concluded: ‘Human racial classification … is now seen to be of virtually no genetic or taxonomic significance’ (p. 397). Here, 50 years after the paper's publication, the goal is to understand the origins and legacy of the paper. Aided by insights from published papers and interviews with several of Lewontin's contemporaries, I review the 1972 paper, asking about the intellectual background that led to the publication of the paper, the development of its impact, the critiques of the work and the work's application and limitations today. The hope is that by gaining a clearer understanding of the origin and reasoning of the paper, we might dispel various confusions about the result and sharpen an understanding of the enduring value and insight the result provides. This article is part of the theme issue ‘Celebrating 50 years since Lewontin's apportionment of human diversity’.
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Affiliation(s)
- John Novembre
- Department of Human Genetics, University of Chicago, Chicago, 60637, IL
- Department of Ecology and Evolution, University of Chicago, Chicago, 60637, IL
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10
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Mathieson I, Terhorst J. Direct detection of natural selection in Bronze Age Britain. Genome Res 2022; 32:2057-2067. [PMID: 36316157 PMCID: PMC9808619 DOI: 10.1101/gr.276862.122] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 08/29/2022] [Indexed: 11/04/2022]
Abstract
We developed a novel method for efficiently estimating time-varying selection coefficients from genome-wide ancient DNA data. In simulations, our method accurately recovers selective trajectories and is robust to misspecification of population size. We applied it to a large data set of ancient and present-day human genomes from Britain and identified seven loci with genome-wide significant evidence of selection in the past 4500 yr. Almost all of them can be related to increased vitamin D or calcium levels, suggesting strong selective pressure on these or related phenotypes. However, the strength of selection on individual loci varied substantially over time, suggesting that cultural or environmental factors moderated the genetic response. Of 28 complex anthropometric and metabolic traits, skin pigmentation was the only one with significant evidence of polygenic selection, further underscoring the importance of phenotypes related to vitamin D. Our approach illustrates the power of ancient DNA to characterize selection in human populations and illuminates the recent evolutionary history of Britain.
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Affiliation(s)
- Iain Mathieson
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Jonathan Terhorst
- Department of Statistics, University of Michigan, Ann Arbor, Michigan 48109, USA
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11
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Further insight into the global variability of the OCA2-HERC2 locus for human pigmentation from multiallelic markers. Sci Rep 2021; 11:22530. [PMID: 34795370 PMCID: PMC8602267 DOI: 10.1038/s41598-021-01940-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 11/02/2021] [Indexed: 11/20/2022] Open
Abstract
The OCA2-HERC2 locus is responsible for the greatest proportion of eye color variation in humans. Numerous studies extensively described both functional SNPs and associated patterns of variation over this region. The goal of our study is to examine how these haplotype structures and allelic associations vary when highly variable markers such as microsatellites are used. Eleven microsatellites spanning 357 Kb of OCA2-HERC2 genes are analyzed in 3029 individuals from worldwide populations. We found that several markers display large differences in allele frequency (10% to 35% difference) among Europeans, East Asians and Africans. In Europe, the alleles showing increased frequency can also discriminate individuals with (IrisPlex) predicted blue and brown eyes. Distinct haplotypes are identified around the variants C and T of the functional SNP rs12913832 (associated to blue eyes), with linkage disequilibrium r2 values significant up to 237 Kb. The haplotype carrying the allele rs12913832 C has high frequency (76%) in blue eye predicted individuals (30% in brown eye predicted individuals), while the haplotype associated to the allele rs12913832 T is restricted to brown eye predicted individuals. Finally, homozygosity values reach levels of 91% near rs12913832. Odds ratios show values of 4.2, 7.4 and 10.4 for four markers around rs12913832 and 7.1 for their core haplotype. Hence, this study provides an example on the informativeness of multiallelic markers that, despite their current limited potential contribution to forensic eye color prediction, supports the use of microsatellites for identifying causing variants showing similar genetic features and history.
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12
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GWAS Identifies Multiple Genetic Loci for Skin Color in Korean Women. J Invest Dermatol 2021; 142:1077-1084. [PMID: 34648798 DOI: 10.1016/j.jid.2021.08.440] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 08/11/2021] [Accepted: 08/13/2021] [Indexed: 12/29/2022]
Abstract
Human skin color is largely determined by genetic factors. Recent GWASs have reported several genetic variants associated with skin color, mostly in European and African populations. In this study, we performed GWAS in 17,019 Korean women to identify genetic variants associated with facial skin color, quantitatively measured as CIELAB color index. We identified variants in three, one, and six genomic loci associated with facial skin color index L∗, a∗, and b∗ values, respectively, and replicated the associations (combined analysis P-value < 5.0 × 10-8). The significant loci included variants in known genes (OCA2 rs74653330, BNC2 rs16935073, rs72620727 near KITLG, and SLC6A17 rs6689641) and to our knowledge previously unreported genes (SCARB1 rs10846744, SYN2 rs12629034, and LINC00486 rs6543678). This is GWAS to elucidate genetic variants of facial skin color in a Korean female population. Further functional characterizations of the investigated genes are warranted to elucidate their contribution to skin pigmentation-related traits.
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13
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Weisz NA, Roberts KA, Hardy WR. Reliability of phenotype estimation and extended classification of ancestry using decedent samples. Int J Legal Med 2021; 135:2221-2233. [PMID: 34436656 DOI: 10.1007/s00414-021-02631-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 06/04/2021] [Indexed: 11/30/2022]
Abstract
The Illumina® MiSeq FGx™, in conjunction with the ForenSeq™ DNA Signature Prep kit, produces genotypes of the CODIS-required short tandem repeats and provides phenotype and biogeographical ancestry estimations via phenotype-informative and ancestry-informative markers, respectively. Although both markers have been validated for use in forensic biology, there is little data to determine the practical utility of these estimations to assist in identifying missing persons using decedent casework samples. The accuracy and utility of phenotypic and ancestral estimations were investigated for 300 samples received by the Los Angeles County Department of Medical Examiner-Coroner. piSNP genotypes were translated into hair and eye colors using the Forenseq™ Universal Analysis Software (UAS) on the MiSeq FGx™ and the HIrisPlex System, and statistical accuracy was evaluated in context with the reported decedent characteristics. Similarly, estimates of each decedent's biogeographical ancestry were compared to assess the efficacy of these markers to predict ancestry correctly. The average UAS and the HIrisPlex system prediction accuracy for brown and blue eyes were 95.3% and 96.2%, respectively. Intermediate eye color could not be predicted with high accuracy using either system. Other than the black hair phenotype reporting an accuracy that exceeded 90% using either system, hair color was also too variable to be predicted with high accuracy. The FROG-kb database distinguishes decedents adequately beyond the Asian, African, European, and Admixed American global ancestries provided by the MiSeq FGx™ UAS PCA plots. FROG-kb correctly identified Middle Eastern, Pacific Islander, Latin American, or Jewish ancestries with accuracies of 70.0%, 81.8%, 73.8%, and 86.7%, respectively.
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Affiliation(s)
- Naomi A Weisz
- School of Criminal Justice and Criminalistics, California State University, Los Angeles, 1800 Paseo Rancho Castilla, Los Angeles, CA, 90032, USA
| | - Katherine A Roberts
- School of Criminal Justice and Criminalistics, California State University, Los Angeles, 1800 Paseo Rancho Castilla, Los Angeles, CA, 90032, USA. .,California Forensic Science Institute, California State University, Los Angeles, 5151 State University Drive, Los Angeles, CA, 90032, USA.
| | - W Reef Hardy
- Human Genomics Unit, Los Angeles County Department of Medical Examiner-Coroner, 1104 N Mission Road, Los Angeles, CA, 90033, USA
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14
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Lucock MD, Jones PR, Veysey M, Thota R, Garg M, Furst J, Martin C, Yates Z, Scarlett CJ, Jablonski NG, Chaplin G, Beckett EL. Biophysical evidence to support and extend the vitamin D-folate hypothesis as a paradigm for the evolution of human skin pigmentation. Am J Hum Biol 2021; 34:e23667. [PMID: 34418235 DOI: 10.1002/ajhb.23667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE To test the "vitamin D-folate hypothesis for the evolution of human skin pigmentation." METHODS Total ozone mapping spectrometer (TOMS) satellite data were used to examine surface UV-irradiance in a large (n = 649) Australian cross-sectional study population. Genetic analysis was used to score vitamin D- and folate-related gene polymorphisms (n = 22), along with two pigmentation gene variants (IRF4-rs12203592/HERC2-rs12913832). Red cell folate and vitamin D3 were measured by immunoassay and HPLC, respectively. RESULTS Ultraviolet radiation (UVR) and pigmentation genes interact to modify blood vitamin levels; Light skin IRF4-TT genotype has greatest folate loss while light skin HERC2-GG genotype has greatest vitamin D3 synthesis (reflected in both TOMS and seasonal data). UV-wavelength exhibits a dose-response relationship in folate loss within light skin IRF4-TT genotype (305 > 310 > 324 > 380 nm). Significant vitamin D3 photosynthesis only occurs within light skin HERC2-GG genotype, and is maximal at 305 nm. Three dietary antioxidants (vitamins C, E, and β-carotene) interact with UVR and pigmentation genes preventing oxidative loss of labile reduced folate vitamers, with greatest benefit in light skin IRF4-TT subjects. The putative photosensitiser, riboflavin, did not sensitize red cell folate to UVR and actually afforded protection. Four genes (5xSNPs) influenced blood vitamin levels when stratified by pigmentation genotype; MTHFR-rs1801133/rs1801131, TS-rs34489327, CYP24A-rs17216707, and VDR-ApaI-rs7975232. Lightest IRF4-TT/darkest HERC2-AA genotype combination (greatest folate loss/lowest vitamin D3 synthesis) has 0% occurrence. The opposing, commonest (39%) compound genotype (darkest IRF4-CC/lightest HERC2-GG) permits least folate loss and greatest synthesis of vitamin D3 . CONCLUSION New biophysical evidence supports the vitamin D-folate hypothesis for evolution of skin pigmentation.
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Affiliation(s)
- Mark D Lucock
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Patrice R Jones
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | | | - Rohith Thota
- Nutraceuticals Research Group, University of Newcastle, Callaghan, New South Wales, Australia.,Metabolism and Nutrition, Riddet Institute, Massey University, Palmerston North, New Zealand
| | - Manohar Garg
- Nutraceuticals Research Group, University of Newcastle, Callaghan, New South Wales, Australia
| | - John Furst
- Maths and Physical Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Charlotte Martin
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Zoe Yates
- Biomedical Sciences and Pharmacy, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Christopher J Scarlett
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Nina G Jablonski
- Anthropology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - George Chaplin
- Anthropology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Emma L Beckett
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
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15
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Irving-Pease EK, Muktupavela R, Dannemann M, Racimo F. Quantitative Human Paleogenetics: What can Ancient DNA Tell us About Complex Trait Evolution? Front Genet 2021; 12:703541. [PMID: 34422004 PMCID: PMC8371751 DOI: 10.3389/fgene.2021.703541] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/08/2021] [Indexed: 12/13/2022] Open
Abstract
Genetic association data from national biobanks and large-scale association studies have provided new prospects for understanding the genetic evolution of complex traits and diseases in humans. In turn, genomes from ancient human archaeological remains are now easier than ever to obtain, and provide a direct window into changes in frequencies of trait-associated alleles in the past. This has generated a new wave of studies aiming to analyse the genetic component of traits in historic and prehistoric times using ancient DNA, and to determine whether any such traits were subject to natural selection. In humans, however, issues about the portability and robustness of complex trait inference across different populations are particularly concerning when predictions are extended to individuals that died thousands of years ago, and for which little, if any, phenotypic validation is possible. In this review, we discuss the advantages of incorporating ancient genomes into studies of trait-associated variants, the need for models that can better accommodate ancient genomes into quantitative genetic frameworks, and the existing limits to inferences about complex trait evolution, particularly with respect to past populations.
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Affiliation(s)
- Evan K. Irving-Pease
- Lundbeck Foundation GeoGenetics Centre, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark
| | - Rasa Muktupavela
- Lundbeck Foundation GeoGenetics Centre, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark
| | - Michael Dannemann
- Center for Genomics, Evolution and Medicine, Institute of Genomics, University of Tartu, Tartu, Estonia
| | - Fernando Racimo
- Lundbeck Foundation GeoGenetics Centre, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark
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16
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Jablonski NG. The evolution of human skin pigmentation involved the interactions of genetic, environmental, and cultural variables. Pigment Cell Melanoma Res 2021; 34:707-729. [PMID: 33825328 PMCID: PMC8359960 DOI: 10.1111/pcmr.12976] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/30/2021] [Accepted: 04/03/2021] [Indexed: 12/12/2022]
Abstract
The primary biological role of human skin pigmentation is as a mediator of penetration of ultraviolet radiation (UVR) into the deep layers of skin and the cutaneous circulation. Since the origin of Homo sapiens, dark, protective constitutive pigmentation and strong tanning abilities have been favored under conditions of high UVR and represent the baseline condition for modern humans. The evolution of partly depigmented skin and variable tanning abilities has occurred multiple times in prehistory, as populations have dispersed into environments with lower and more seasonal UVR regimes, with unique complements of genes and cultural practices. The evolution of extremes of dark pigmentation and depigmentation has been rare and occurred only under conditions of extremely high or low environmental UVR, promoted by positive selection on variant pigmentation genes followed by limited gene flow. Over time, the evolution of human skin pigmentation has been influenced by the nature and course of human dispersals and modifications of cultural practices, which have modified the nature and actions of skin pigmentation genes. Throughout most of prehistory and history, the evolution of human skin pigmentation has been a contingent and non-deterministic process.
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Affiliation(s)
- Nina G. Jablonski
- Department of AnthropologyThe Pennsylvania State UniversityUniversity ParkPAUSA
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17
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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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18
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Feng Y, McQuillan MA, Tishkoff SA. Evolutionary genetics of skin pigmentation in African populations. Hum Mol Genet 2021; 30:R88-R97. [PMID: 33438000 PMCID: PMC8117430 DOI: 10.1093/hmg/ddab007] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/07/2021] [Accepted: 01/07/2021] [Indexed: 12/14/2022] Open
Abstract
Skin color is a highly heritable human trait, and global variation in skin pigmentation has been shaped by natural selection, migration and admixture. Ethnically diverse African populations harbor extremely high levels of genetic and phenotypic diversity, and skin pigmentation varies widely across Africa. Recent genome-wide genetic studies of skin pigmentation in African populations have advanced our understanding of pigmentation biology and human evolutionary history. For example, novel roles in skin pigmentation for loci near MFSD12 and DDB1 have recently been identified in African populations. However, due to an underrepresentation of Africans in human genetic studies, there is still much to learn about the evolutionary genetics of skin pigmentation. Here, we summarize recent progress in skin pigmentation genetics in Africans and discuss the importance of including more ethnically diverse African populations in future genetic studies. In addition, we discuss methods for functional validation of adaptive variants related to skin pigmentation.
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Affiliation(s)
- Yuanqing Feng
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael A McQuillan
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sarah A Tishkoff
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
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19
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Wakamatsu K, Zippin JH, Ito S. Chemical and biochemical control of skin pigmentation with special emphasis on mixed melanogenesis. Pigment Cell Melanoma Res 2021; 34:730-747. [PMID: 33751833 DOI: 10.1111/pcmr.12970] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 02/24/2021] [Accepted: 03/07/2021] [Indexed: 02/06/2023]
Abstract
Melanins are widely distributed in animals and plants; in vertebrates, most melanins are present on the body surface. The diversity of pigmentation in vertebrates is mainly attributed to the quantity and ratio of eumelanin and pheomelanin synthesis. Most natural melanin pigments in animals consist of both eumelanin and pheomelanin in varying ratios, and thus, their combined synthesis is called "mixed melanogenesis." Gene expression is an established mechanism for controlling melanin synthesis; however, there are multiple factors that affect melanin synthesis besides gene expression. Due to the differential sensitivity of the eumelanin and pheomelanin synthetic pathways to pH, melanosomal pH likely plays a major role in mixed melanogenesis. Here, we focused on various factors affecting mixed melanogenesis including (1) chemical regulation of melanin synthesis, (2) melanosomal pH regulation during normal melanogenesis and effect on mixed melanogenesis, and (3) mechanisms of melanosomal pH control (proton pumps, channels, transporters, and signaling pathways).
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Affiliation(s)
- Kazumasa Wakamatsu
- Institute for Melanin Chemistry, Fujita Health University, Toyoake, Japan
| | - Jonathan H Zippin
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY, USA
| | - Shosuke Ito
- Institute for Melanin Chemistry, Fujita Health University, Toyoake, Japan
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20
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Huang X, Wang S, Jin L, He Y. Dissecting dynamics and differences of selective pressures in the evolution of human pigmentation. Biol Open 2021; 10:bio056523. [PMID: 33495209 PMCID: PMC7888712 DOI: 10.1242/bio.056523] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 12/21/2020] [Indexed: 01/05/2023] Open
Abstract
Human pigmentation is a highly diverse and complex trait among populations and has drawn particular attention from both academic and non-academic investigators for thousands of years. Previous studies detected selection signals in several human pigmentation genes, but few studies have integrated contribution from multiple genes to the evolution of human pigmentation. Moreover, none has quantified selective pressures on human pigmentation over epochs and between populations. Here, we dissect dynamics and differences of selective pressures during different periods and between distinct populations with new approaches. We use genotype data of 19 genes associated with human pigmentation from 17 publicly available datasets and obtain data for 2346 individuals of six representative population groups from across the world. Our results quantify the strength of natural selection on light pigmentation not only in modern Europeans (0.0259/generation) but also in proto-Eurasians (0.00650/generation). Our results also suggest that several derived alleles associated with human dark pigmentation may be under positive directional selection in some African populations. Our study provides the first attempt to quantitatively investigate the dynamics of selective pressures during different time periods in the evolution of human pigmentation.This article has an associated First Person interview with the first author of the article.
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Affiliation(s)
- Xin Huang
- Chinese Academy of Sciences Key Laboratory of Computational Biology, Chinese Academy of Sciences-Max Planck Society Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Sijia Wang
- Chinese Academy of Sciences Key Laboratory of Computational Biology, Chinese Academy of Sciences-Max Planck Society Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Li Jin
- Chinese Academy of Sciences Key Laboratory of Computational Biology, Chinese Academy of Sciences-Max Planck Society Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Yungang He
- Key Laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
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21
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Lucock M. Vitamin-related phenotypic adaptation to exposomal factors: The folate-vitamin D-exposome triad. Mol Aspects Med 2021; 87:100944. [PMID: 33551238 DOI: 10.1016/j.mam.2021.100944] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 01/02/2021] [Accepted: 01/25/2021] [Indexed: 12/16/2022]
Abstract
The biological role of two key vitamins, folic acid and vitamin D is so fundamental to life processes, it follows that their UV sensitivity, dietary abundance (both key exposomal factors) and variability in dependent genes will modify their functional efficacy, particularly in the context of maintaining the integrity and function of genome and epigenome. This article therefore examines folate and vitamin D-related phenotypic adaptation to environmental factors which vary across the human life cycle as well as over an evolutionary time-scale. Molecular mechanisms, key nutrigenomic factors, phenotypic maladaptation and evolutionary models are discussed.
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Affiliation(s)
- Mark Lucock
- School of Environmental & Life Sciences, University of Newcastle, PO Box 127, Brush Rd, Ourimbah, NSW, 2258, Australia.
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22
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Norton HL. The color of normal: How a Eurocentric focus erases pigmentation complexity. Am J Hum Biol 2020; 33:e23554. [PMID: 33337560 DOI: 10.1002/ajhb.23554] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/03/2020] [Accepted: 12/06/2020] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVES Skin pigmentation is both a highly variable and highly visible human phenotypic trait. Investigations into the biology and origins of this variation have been the focus of research in the fields of dermatology, anthropology, and forensic science, among others. This manuscript explores how much of what we know about the biology, genetics, and evolutionary origins of pigmentation has been strongly influenced by investigations and applications that focus on lighter skin. METHODS I reviewed literature from the fields of dermatology, anthropology and evolutionary genetics, and forensic science to assess how perceptions of lighter skin as the "normal" state in humans can shape the ways that knowledge is gathered and applied in these fields. RESULTS This normalization of lighter skin has impacted common tools used in dermatology and shaped the framework of dermatological education. A strong Eurocentric bias has shaped our understanding of the genetic architecture of pigmentary traits, which influences the ways in we understand the evolutionary processes leading to modern pigmentation diversity. Finally, I discuss how these biases in pigmentation genetics work in combination with phenotypic systems that privilege predicting lighter pigmentation variation to impede accurate prediction of intermediate phenotypes, particularly in individuals with ancestry from multiple populations. This can lead to a disproportionate targeting of already over-policed populations with darker skin. CONCLUSIONS Potential changes to how we conceptualize clinical and basic pigmentation research may help to reduce existing health disparities and improve understanding of pigmentation genetic architecture and how this knowledge is applied in forensic contexts.
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Affiliation(s)
- Heather L Norton
- Department of Anthropology, University of Cincinnati, Cincinnati, Ohio, USA
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23
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Le L, Escobar IE, Ho T, Lefkovith AJ, Latteri E, Haltaufderhyde KD, Dennis MK, Plowright L, Sviderskaya EV, Bennett DC, Oancea E, Marks MS. SLC45A2 protein stability and regulation of melanosome pH determine melanocyte pigmentation. Mol Biol Cell 2020; 31:2687-2702. [PMID: 32966160 PMCID: PMC7927184 DOI: 10.1091/mbc.e20-03-0200] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
SLC45A2 encodes a putative transporter expressed primarily in pigment cells. SLC45A2 mutations cause oculocutaneous albinism type 4 (OCA4) and polymorphisms are associated with pigmentation variation, but the localization, function, and regulation of SLC45A2 and its variants remain unknown. We show that SLC45A2 localizes to a cohort of mature melanosomes that only partially overlaps with the cohort expressing the chloride channel OCA2. SLC45A2 expressed ectopically in HeLa cells localizes to lysosomes and raises lysosomal pH, suggesting that in melanocytes SLC45A2 expression, like OCA2 expression, results in the deacidification of maturing melanosomes to support melanin synthesis. Interestingly, OCA2 overexpression compensates for loss of SLC45A2 expression in pigmentation. Analyses of SLC45A2- and OCA2-deficient mouse melanocytes show that SLC45A2 likely functions later during melanosome maturation than OCA2. Moreover, the light skin-associated SLC45A2 allelic F374 variant restores only moderate pigmentation to SLC45A2-deficient melanocytes due to rapid proteasome-dependent degradation resulting in lower protein expression levels in melanosomes than the dark skin-associated allelic L374 variant. Our data suggest that SLC45A2 maintains melanosome neutralization that is initially orchestrated by transient OCA2 activity to support melanization at late stages of melanosome maturation, and that a common allelic variant imparts reduced activity due to protein instability.
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Affiliation(s)
- Linh Le
- Department of Pathology & Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104.,Department of Pathology and Laboratory Medicine and Department of Physiology and.,Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Iliana E Escobar
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI 02912
| | - Tina Ho
- Department of Pathology & Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104.,Department of Pathology and Laboratory Medicine and Department of Physiology and.,Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Ariel J Lefkovith
- Department of Pathology & Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104.,Department of Pathology and Laboratory Medicine and Department of Physiology and.,Cell and Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Emily Latteri
- Department of Pathology & Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104.,Department of Pathology and Laboratory Medicine and Department of Physiology and
| | - Kirk D Haltaufderhyde
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI 02912
| | - Megan K Dennis
- Department of Pathology & Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104.,Department of Pathology and Laboratory Medicine and Department of Physiology and.,Biology Department, Marist College, Poughkeepsie, NY 12601
| | - Lynn Plowright
- Molecular & Clinical Sciences Research Institute, St George's, University of London, London SW17 0RE, UK
| | - Elena V Sviderskaya
- Molecular & Clinical Sciences Research Institute, St George's, University of London, London SW17 0RE, UK
| | - Dorothy C Bennett
- Molecular & Clinical Sciences Research Institute, St George's, University of London, London SW17 0RE, UK
| | - Elena Oancea
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI 02912
| | - Michael S Marks
- Department of Pathology & Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104.,Department of Pathology and Laboratory Medicine and Department of Physiology and
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24
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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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25
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Casella A, Long C, Zhou J, Lai M, O’Lear L, Caplan I, Levine MA, Roizen JD. Differential Frequency of CYP2R1 Variants Across Populations Reveals Pathway Selection for Vitamin D Homeostasis. J Clin Endocrinol Metab 2020; 105:dgaa056. [PMID: 32115644 PMCID: PMC7096315 DOI: 10.1210/clinem/dgaa056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 02/05/2020] [Indexed: 12/31/2022]
Abstract
CONTEXT Normal vitamin D homeostasis is necessary to ensure optimal mineral metabolism. Dietary insufficiency of vitamin D and the lack of sunlight each have well understood roles in vitamin D deficiency; however, the extent to which common genetic variations in vitamin D metabolizing enzymes contribute to alterations in vitamin D homeostasis remains uncertain. OBJECTIVE To examine the possibility that common coding variation in vitamin D metabolizing enzymes alters vitamin D homeostasis we determined the effect of 44 nonsynonymous polymorphisms in CYP2R1, the vitamin D 25-hydroxylase, on enzyme function. RESULTS Twenty-one of these polymorphisms decreased activity, while 2 variants increased activity. The frequency of CYP2R1 alleles with decreased 25-hydroxylase activity is 3 in every 1000 Caucasians and 7 in every 1000 African Americans. In populations where exposure to sunlight is high, alleles with decreased function occur at a frequency as high as 8%. The pattern of selected variation as compared to nonselected variation is consistent with it being the result of positive selection for nonfunctional alleles closer to the equator. To examine this possibility, we examined the variation pattern in another protein in the vitamin D pathway, the vitamin D binding protein (GC protein). The pattern of selected variation in the GC protein as compared to nonselected variation is also consistent with it being the result of positive selection for nonfunctional alleles closer to the equator. CONCLUSIONS CYP2R1 polymorphisms have important effects on vitamin D homeostasis, and the geographic variability of CYP2R1 alleles represents an adaptation to differential exposures to UVB irradiation from sunlight.
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Affiliation(s)
- Alex Casella
- Division of Endocrinology and Diabetes, Department of Pediatrics, Children’s Hospital of Pennsylvania, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Caela Long
- Division of Endocrinology and Diabetes, Department of Pediatrics, Children’s Hospital of Pennsylvania, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Jingman Zhou
- Spark Therapeutics, Inc, Philadelphia, Pennsylvania
| | - Meizan Lai
- Division of Endocrinology and Diabetes, Department of Pediatrics, Children’s Hospital of Pennsylvania, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Lauren O’Lear
- Division of Endocrinology and Diabetes, Department of Pediatrics, Children’s Hospital of Pennsylvania, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Ilana Caplan
- Division of Endocrinology and Diabetes, Department of Pediatrics, Children’s Hospital of Pennsylvania, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Michael A Levine
- Division of Endocrinology and Diabetes, Department of Pediatrics, Children’s Hospital of Pennsylvania, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Jeffrey D Roizen
- Division of Endocrinology and Diabetes, Department of Pediatrics, Children’s Hospital of Pennsylvania, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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26
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Chen Y, Gong Q, Lai J, Song M, Liu Y, Wu Y, Ai J, Long Z. Transcriptome analysis identifies candidate genes associated with skin color variation in Triplophysa siluroides. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2020; 35:100682. [PMID: 32248074 DOI: 10.1016/j.cbd.2020.100682] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 03/24/2020] [Accepted: 03/24/2020] [Indexed: 12/18/2022]
Abstract
In vertebrates, skin pigmentation is the most diverse phenotypic trait, and it is produced by a complex biological process that is often genetically controlled. Recently, two different colors (the typical brown and orange varieties) of Triplophysa siluroides, a species restricted to Yellow River drainage in China, were discovered. In the present study, the skin, brain and liver transcriptomes of T. siluroides of both colors were sequenced to search for genes related to skin pigmentation. Transcriptome sequencing generated 1,484,197,774 clean reads, resulting in a total of 222.6 Gb of sequence. The reads were assembled into 470,788 unigenes with a mean length of 1550 bp and an N50 size of 2944 bp. Functional annotation of the unigene dataset showed that 214,507, 304,161, 112,886, 179,074, 180,064, 184,837 and 82,081 unigenes were significantly matched to entries in the Nr protein, Nt, KO, Swiss-Prot, Pfam, GO and KOG databases, respectively. A differential expression analysis revealed that 2774, 3552 and 1529 unigenes were upregulated and 2720, 2663 and 1103 unigenes were downregulated in the skin, brain and liver of orange-skinned T. siluroides, respectively. Several genes that play key roles in pigmentation, i.e., Agouti, Slc45a2, Cbs, Mift and Slc7a11, showed significantly differential expression between brown and orange fish. In addition, we detected 158,863 simple sequence repeats (SSRs) in the T. siluroides transcriptome, and a total of 201,338 single-nucleotide polymorphisms (SNPs) were discovered in the different transcriptomes. The present results will facilitate further study of the molecular mechanisms of skin pigmentation and marker-assisted breeding of fish with valuable skin colors.
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Affiliation(s)
- Yeyu Chen
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Quan Gong
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Jiansheng Lai
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China.
| | - Mingjiang Song
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Ya Liu
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Yingbin Wu
- Sichuan Juhai Fishery Technology Co., Ltd., Chengdu 610000, China
| | - Jiagui Ai
- Sichuan Juhai Fishery Technology Co., Ltd., Chengdu 610000, China
| | - Zhihai Long
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China.
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27
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Markiewicz E, Idowu OC. Melanogenic Difference Consideration in Ethnic Skin Type: A Balance Approach Between Skin Brightening Applications and Beneficial Sun Exposure. Clin Cosmet Investig Dermatol 2020; 13:215-232. [PMID: 32210602 PMCID: PMC7069578 DOI: 10.2147/ccid.s245043] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 02/13/2020] [Indexed: 12/20/2022]
Abstract
Human skin demonstrates a striking variation in tone and color that is evident among multiple demographic populations. Such characteristics are determined predominantly by the expression of the genes controlling the quantity and quality of melanin, which can alter significantly due to the presence of small nucleotide polymorphism affecting various steps of the melanogenesis process and generally linked to the lighter skin phenotypes. Genetically determined, constitutive skin color is additionally complemented by the facultative melanogenesis and tanning responses; with high levels of melanin and melanogenic factors broadly recognized to have a protective effect against the UVR-induced molecular damage in darker skin. Long-term sun exposure, together with a genetic makeup responsible for the ability to tan or the activity of constitutive melanogenic factors, triggers defects in pigmentation across all ethnic skin types. However, sun exposure also has well documented beneficial effects that manifest at both skin homeostasis and the systemic level, such as synthesis of vitamin D, which is thought to be less efficient in the presence of high levels of melanin or potentially linked to the polymorphism in the genes responsible for skin darkening triggered by UVR. In this review, we discuss melanogenesis in a context of constitutive pigmentation, defined by gene polymorphism in ethnic skin types, and facultative pigmentation that is not only associated with the capacity to protect the skin against photo-damage but could also have an impact on vitamin D synthesis through gene polymorphism. Modulating the activities of melanogenic genes, with the focus on the markers specifically altered by polymorphism combined with differential requirements of sun exposure in ethnic skin types, could enhance the applications of already existing skin brightening factors and provide a novel approach toward improved skin tone and health in personalized skincare.
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Affiliation(s)
- Ewa Markiewicz
- Hexis Lab Limited, The Core, Newcastle Helix, Newcastle Upon Tyne NE4 5TF, UK
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28
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Yang Z, Shi H, Ma P, Zhao S, Kong Q, Bian T, Gong C, Zhao Q, Liu Y, Qi X, Zhang X, Han Y, Liu J, Li Q, Chen H, Su B. Darwinian Positive Selection on the Pleiotropic Effects of KITLG Explain Skin Pigmentation and Winter Temperature Adaptation in Eurasians. Mol Biol Evol 2020; 35:2272-2283. [PMID: 29961894 DOI: 10.1093/molbev/msy136] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Human skin color diversity is considered an adaptation to environmental conditions such as UV radiation. Investigations into the genetic bases of such adaptation have identified a group of pigmentation genes contributing to skin color diversity in African and non-African populations. Here, we present a population analysis of the pigmentation gene KITLG with previously reported signal of Darwinian positive selection in both European and East Asian populations. We demonstrated that there had been recurrent selective events in the upstream and the downstream regions of KITLG in Eurasian populations. More importantly, besides the expected selection on the KITLG variants favoring light skin in coping with the weak UV radiation at high latitude, we observed a KITLG variant showing adaptation to winter temperature. In particular, compared with UV radiation, winter temperature showed a much stronger correlation with the prevalence of the presumably adaptive KITLG allele in Asian populations. This observation was further supported by the in vitro functional test at low temperature. Consequently, the pleiotropic effects of KITLG, that is, pigmentation and thermogenesis were both targeted by natural selection that acted on different KITLG sequence variants, contributing to the adaptation of Eurasians to both UV radiation and winter temperature at high latitude areas.
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Affiliation(s)
- Zhaohui Yang
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, China.,State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.,Yunnan Provincial Academy of Science and Technology, Kunming, China
| | - Hong Shi
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, China.,Yunnan Provincial Academy of Science and Technology, Kunming, China
| | - Pengcheng Ma
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Shilei Zhao
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Qinghong Kong
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Tianhao Bian
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, China.,Yunnan Provincial Academy of Science and Technology, Kunming, China
| | - Chao Gong
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, China.,Yunnan Provincial Academy of Science and Technology, Kunming, China
| | - Qi Zhao
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, China.,Yunnan Provincial Academy of Science and Technology, Kunming, China
| | - Yuan Liu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Xuebin Qi
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Xiaoming Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Yinglun Han
- College of Life Science, Liaoning Normal University, Dalian, China
| | - Jiewei Liu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Qingwei Li
- College of Life Science, Liaoning Normal University, Dalian, China
| | - Hua Chen
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Bing Su
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.,Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China
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29
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The Evolutionary History of Human Skin Pigmentation. J Mol Evol 2019; 88:77-87. [PMID: 31363820 DOI: 10.1007/s00239-019-09902-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 07/16/2019] [Indexed: 02/07/2023]
Abstract
Skin pigmentation is a complex, conspicuous, highly variable human trait that exhibits a remarkable correlation with latitude. The evolutionary history and genetic basis of skin color variation has been the subject of intense research in the last years. This article reviews the major hypotheses explaining skin color diversity and explores the implications of recent findings about the genes associated with skin pigmentation for understanding the evolutionary forces that have shaped the current patterns of skin color variation. A major aspect of these findings is that the genetic basis of skin color is less simple than previously thought and that geographic variation in skin pigmentation was influenced by the concerted action of different types of natural selection, rather than just by selective sweeps in a few key genes.
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30
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Lona-Durazo F, Hernandez-Pacheco N, Fan S, Zhang T, Choi J, Kovacs MA, Loftus SK, Le P, Edwards M, Fortes-Lima CA, Eng C, Huntsman S, Hu D, Gómez-Cabezas EJ, Marín-Padrón LC, Grauholm J, Mors O, Burchard EG, Norton HL, Pavan WJ, Brown KM, Tishkoff S, Pino-Yanes M, Beleza S, Marcheco-Teruel B, Parra EJ. Meta-analysis of GWA studies provides new insights on the genetic architecture of skin pigmentation in recently admixed populations. BMC Genet 2019; 20:59. [PMID: 31315583 PMCID: PMC6637524 DOI: 10.1186/s12863-019-0765-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 07/08/2019] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Association studies in recently admixed populations are extremely useful to identify the genetic architecture of pigmentation, due to their high genotypic and phenotypic variation. However, to date only four Genome-Wide Association Studies (GWAS) have been carried out in these populations. RESULTS We present a GWAS of skin pigmentation in an admixed sample from Cuba (N = 762). Additionally, we conducted a meta-analysis including the Cuban sample, and admixed samples from Cape Verde, Puerto Rico and African-Americans from San Francisco. This meta-analysis is one of the largest efforts so far to characterize the genetic basis of skin pigmentation in admixed populations (N = 2,104). We identified five genome-wide significant regions in the meta-analysis, and explored if the markers observed in these regions are associated with the expression of relevant pigmentary genes in human melanocyte cultures. In three of the regions identified in the meta-analysis (SLC24A5, SLC45A2, and GRM5/TYR), the association seems to be driven by non-synonymous variants (rs1426654, rs16891982, and rs1042602, respectively). The rs16891982 polymorphism is strongly associated with the expression of the SLC45A2 gene. In the GRM5/TYR region, in addition to the rs1042602 non-synonymous SNP located on the TYR gene, variants located in the nearby GRM5 gene have an independent effect on pigmentation, possibly through regulation of gene expression of the TYR gene. We also replicated an association recently described near the MFSD12 gene on chromosome 19 (lead variant rs112332856). Additionally, our analyses support the presence of multiple signals in the OCA2/HERC2/APBA2 region on chromosome 15. A clear causal candidate is the HERC2 intronic variant rs12913832, which has a profound influence on OCA2 expression. This variant has pleiotropic effects on eye, hair, and skin pigmentation. However, conditional and haplotype-based analyses indicate the presence of other variants with independent effects on melanin levels in OCA2 and APBA2. Finally, a follow-up of genome-wide signals identified in a recent GWAS for tanning response indicates that there is a substantial overlap in the genetic factors influencing skin pigmentation and tanning response. CONCLUSIONS Our meta-analysis of skin pigmentation GWAS in recently admixed populations provides new insights about the genetic architecture of this complex trait.
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Affiliation(s)
- Frida Lona-Durazo
- Department of Anthropology, University of Toronto at Mississauga, Health Sciences Complex, room 352, Mississauga, Ontario L5L 1C6 Canada
| | - Natalia Hernandez-Pacheco
- Research Unit, Hospital Universitario N.S. de Candelaria, Universidad de La Laguna, Santa Cruz de Tenerife, Spain
- Genomics and Health Group, Department of Biochemistry, Microbiology, Cell Biology and Genetics, Universidad de La Laguna, La Laguna, Tenerife, Spain
| | - Shaohua Fan
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - Tongwu Zhang
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, USA
| | - Jiyeon Choi
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, USA
| | - Michael A. Kovacs
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, USA
| | - Stacie K. Loftus
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, USA
| | - Phuong Le
- Department of Anthropology, University of Toronto at Mississauga, Health Sciences Complex, room 352, Mississauga, Ontario L5L 1C6 Canada
| | - Melissa Edwards
- Department of Anthropology, University of Toronto at Mississauga, Health Sciences Complex, room 352, Mississauga, Ontario L5L 1C6 Canada
| | - Cesar A. Fortes-Lima
- Evolutionary Anthropology Team, Laboratory Eco-Anthropology and Ethno-Biology UMR7206, CNRS-MNHN-University Paris Diderot, Musée de l’Homme, Paris, France
- Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Celeste Eng
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA USA
| | - Scott Huntsman
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA USA
| | - Donglei Hu
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA USA
| | | | | | - Jonas Grauholm
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark
| | - Ole Mors
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- The Lundbeck Foundation Initiative for Integrative Psychiatric Research, Aarhus University, Aarhus, Denmark
- Psychiatric Department, Aarhus University Hospital, Aarhus, Denmark
| | - Esteban G. Burchard
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA USA
| | - Heather L. Norton
- Department of Anthropology, University of Cincinnati, Cincinnati, USA
| | - William J. Pavan
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, USA
| | - Kevin M. Brown
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, USA
| | - Sarah Tishkoff
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA USA
| | - Maria Pino-Yanes
- Genomics and Health Group, Department of Biochemistry, Microbiology, Cell Biology and Genetics, Universidad de La Laguna, La Laguna, Tenerife, Spain
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
- Instituto de Tecnologías Biomédicas (ITB), Universidad de La Laguna, Santa Cruz de Tenerife, Spain
| | - Sandra Beleza
- Department of Genetics and Genome Biology, College of Life Sciences, University of Leicester, Leicester, UK
| | | | - Esteban J. Parra
- Department of Anthropology, University of Toronto at Mississauga, Health Sciences Complex, room 352, Mississauga, Ontario L5L 1C6 Canada
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31
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Abstract
Human skin and hair color are visible traits that can vary dramatically within and across ethnic populations. The genetic makeup of these traits-including polymorphisms in the enzymes and signaling proteins involved in melanogenesis, and the vital role of ion transport mechanisms operating during the maturation and distribution of the melanosome-has provided new insights into the regulation of pigmentation. A large number of novel loci involved in the process have been recently discovered through four large-scale genome-wide association studies in Europeans, two large genetic studies of skin color in Africans, one study in Latin Americans, and functional testing in animal models. The responsible polymorphisms within these pigmentation genes appear at different population frequencies, can be used as ancestry-informative markers, and provide insight into the evolutionary selective forces that have acted to create this human diversity.
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Affiliation(s)
- William J Pavan
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Richard A Sturm
- Dermatology Research Centre, The University of Queensland Diamantina Institute, The University of Queensland, Brisbane, Queensland 4102, Australia;
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32
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Zaorska K, Zawierucha P, Nowicki M. Prediction of skin color, tanning and freckling from DNA in Polish population: linear regression, random forest and neural network approaches. Hum Genet 2019; 138:635-647. [PMID: 30980179 PMCID: PMC6554257 DOI: 10.1007/s00439-019-02012-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 04/08/2019] [Indexed: 12/16/2022]
Abstract
Predicting phenotypes from DNA has recently become extensively studied field in forensic research and is referred to as Forensic DNA Phenotyping. Systems based on single nucleotide polymorphisms for accurate prediction of iris, hair and skin color in global population, independent of bio-geographical ancestry, have recently been introduced. Here, we analyzed 14 SNPs for distinct skin pigmentation traits in a homogeneous cohort of 222 Polish subjects. We compared three different algorithms: General Linear Model based on logistic regression, Random Forest and Neural Network in 18 developed prediction models. We demonstrate Random Forest to be the most accurate algorithm for 3- and 4-category estimations (total of 58.3% correct calls for skin color prediction, 47.2% for tanning prediction, 50% for freckling prediction). Binomial Logistic Regression was the best approach in 2-category estimations (total of 69.4% correct calls, AUC = 0.673 for tanning prediction; total of 52.8% correct calls, AUC = 0.537 for freckling prediction). Our study confirms the association of rs12913832 (HERC2) with all three skin pigmentation traits, but also variants associated solely with certain pigmentation traits, namely rs6058017 and rs4911414 (ASIP) with skin sensitivity to sun and tanning abilities, rs12203592 (IRF4) with freckling and rs4778241 and rs4778138 (OCA2) with skin color and tanning. Finally, we assessed significant differences in allele frequencies in comparison with CEU data and our study provides a starting point for the development of prediction models for homogeneous populations with less internal differentiation than in the global predictive testing.
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Affiliation(s)
- Katarzyna Zaorska
- Department of Histology and Embryology, University of Medical Sciences, 60-781, Poznan, Poland.
| | - Piotr Zawierucha
- Department of Anatomy, University of Medical Sciences, 60-781, Poznan, Poland
| | - Michał Nowicki
- Department of Histology and Embryology, University of Medical Sciences, 60-781, Poznan, Poland
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33
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Gong Y, Hu M, Xu S, Wang B, Wang C, Mu X, Xu P, Jiang Y. Comparative transcriptome analysis reveals expression signatures of albino Russian sturgeon, Acipenseriformes gueldenstaedtii. Mar Genomics 2019; 46:1-7. [PMID: 30852186 DOI: 10.1016/j.margen.2019.02.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 01/24/2019] [Accepted: 02/16/2019] [Indexed: 01/03/2023]
Abstract
Albinism is a genetically inherited condition that is caused by a series of genetic abnormalities leading to a reduction in melanin production. Russian sturgeon is one of the most valuable freshwater fish species worldwide, and albino individuals have been found in fish farms. Due to its complicated genome and scarce genome-wide genetic resources, the underlying molecular basis of albinism in Russian sturgeon is unknown. In the present study, we first generated transcriptome profile of Acipenser gueldenstaedtii using pooled tissues, which provided reliable reference sequences for future molecular genetic studies. A total of 369,441 contigs were assembled, corresponding to 32,965 unique genes. A comparative analysis of the transcripts from the skin of albino and wildtype individuals was conducted afterwards. A total of 785 unique genes were differentially expressed, including the upregulation of 385 genes and the downregulation of 400 genes in albino individuals. The expression pattern of 16 selected differentially expressed genes was validated using qRT-PCR. Additional annotation, GO enrichment analysis and gene pathway analysis indicated that the melanogenesis pathway may be interrupted in albinism. Eight potential causative genes that were highly likely to be responsible for sturgeon albinism were identified, including Dct, Tyrp1b, Slc45a2, Ctns, Pmela, Pmelb, Cd63, and Bloc1s3, which were found to be significantly down-regulated in albino Russian sturgeon. Moreover, a sliding window analysis of the ratio of nonsynonymous to synonymous nucleotide substitution rates (Ka/Ks) ratios indicated that seven out of the eight genes underwent positive selection during evolution. Our results provide a valuable basis for understanding the molecular mechanism of albinism in fish species and will facilitate future genetic selection and breeding of sturgeon with market-favored traits in aquaculture.
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Affiliation(s)
- Yiwen Gong
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture and Rural Affairs, CAFS Key Laboratory of Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing, China
| | - Mou Hu
- Hangzhou Qiandaohu Xunlong Sci-Tech Development Company Limited, Quzhou, China
| | - Shijian Xu
- Hangzhou Qiandaohu Xunlong Sci-Tech Development Company Limited, Quzhou, China
| | - Bin Wang
- Hangzhou Qiandaohu Xunlong Sci-Tech Development Company Limited, Quzhou, China
| | - Chunlin Wang
- Key Laboratory of Applied Marine Biotechnology (Ningbo University), Ministry of Education, Ningbo, China
| | - Xidong Mu
- Key Laboratory of Tropical & Subtropical Fishery Resource Application and Cultivation, Ministry of Agriculture and Rural Affairs, Guangzhou, China
| | - Peng Xu
- Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen University, Xiamen, China
| | - Yanliang Jiang
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture and Rural Affairs, CAFS Key Laboratory of Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing, China; Hangzhou Qiandaohu Xunlong Sci-Tech Development Company Limited, Quzhou, China; Key Laboratory of Applied Marine Biotechnology (Ningbo University), Ministry of Education, Ningbo, China.
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34
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Quillen EE, Norton HL, Parra EJ, Lona-Durazo F, Ang KC, Illiescu FM, Pearson LN, Shriver MD, Lasisi T, Gokcumen O, Starr I, Lin YL, Martin AR, Jablonski NG. Shades of complexity: New perspectives on the evolution and genetic architecture of human skin. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 168 Suppl 67:4-26. [PMID: 30408154 DOI: 10.1002/ajpa.23737] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 09/17/2018] [Accepted: 09/20/2018] [Indexed: 02/06/2023]
Abstract
Like many highly variable human traits, more than a dozen genes are known to contribute to the full range of skin color. However, the historical bias in favor of genetic studies in European and European-derived populations has blinded us to the magnitude of pigmentation's complexity. As deliberate efforts are being made to better characterize diverse global populations and new sequencing technologies, better measurement tools, functional assessments, predictive modeling, and ancient DNA analyses become more widely accessible, we are beginning to appreciate how limited our understanding of the genetic bases of human skin color have been. Novel variants in genes not previously linked to pigmentation have been identified and evidence is mounting that there are hundreds more variants yet to be found. Even for genes that have been exhaustively characterized in European populations like MC1R, OCA2, and SLC24A5, research in previously understudied groups is leading to a new appreciation of the degree to which genetic diversity, epistatic interactions, pleiotropy, admixture, global and local adaptation, and cultural practices operate in population-specific ways to shape the genetic architecture of skin color. Furthermore, we are coming to terms with how factors like tanning response and barrier function may also have influenced selection on skin throughout human history. By examining how our knowledge of pigmentation genetics has shifted in the last decade, we can better appreciate how far we have come in understanding human diversity and the still long road ahead for understanding many complex human traits.
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Affiliation(s)
- Ellen E Quillen
- Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina.,Center for Precision Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Heather L Norton
- Department of Anthropology, University of Cincinnati, Cincinnati, Ohio
| | - Esteban J Parra
- Department of Anthropology, University of Toronto - Mississauga, Mississauga, Ontario, Canada
| | - Frida Lona-Durazo
- Department of Anthropology, University of Toronto - Mississauga, Mississauga, Ontario, Canada
| | - Khai C Ang
- Department of Pathology and Jake Gittlen Laboratories for Cancer Research, Penn State College of Medicine, Hershey, Pennsylvania
| | - Florin Mircea Illiescu
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom.,Centro de Estudios Interculturales e Indígenas - CIIR, P. Universidad Católica de Chile, Santiago, Chile
| | - Laurel N Pearson
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania
| | - Mark D Shriver
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania
| | - Tina Lasisi
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania
| | - Omer Gokcumen
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo, New York
| | - Izzy Starr
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo, New York
| | - Yen-Lung Lin
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo, New York
| | - Alicia R Martin
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Massachusetts.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, Massachusetts
| | - Nina G Jablonski
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania
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35
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N’Diaye A, Haile JK, Nilsen KT, Walkowiak S, Ruan Y, Singh AK, Clarke FR, Clarke JM, Pozniak CJ. Haplotype Loci Under Selection in Canadian Durum Wheat Germplasm Over 60 Years of Breeding: Association With Grain Yield, Quality Traits, Protein Loss, and Plant Height. FRONTIERS IN PLANT SCIENCE 2018; 9:1589. [PMID: 30455711 PMCID: PMC6230583 DOI: 10.3389/fpls.2018.01589] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 10/15/2018] [Indexed: 05/21/2023]
Abstract
Durum wheat was introduced in the southern prairies of western Canada in the late nineteenth century. Breeding efforts have mainly focused on improving quality traits to meet the pasta industry demands. For this study, 192 durum wheat lines were genotyped using the Illumina 90K Infinium iSelect assay, and resulted in a total of 14,324 polymorphic SNPs. Genetic diversity changed over time, declining during the first 20 years of breeding in Canada, then increased in the late 1980s and early 1990s. We scanned the genome for signatures of selection, using the total variance Fst-based outlier detection method (Lositan), the hierarchical island model (Arlequin) and the Bayesian genome scan method (BayeScan). A total of 407 outliers were identified and clustered into 84 LD-based haplotype loci, spanning all 14 chromosomes of the durum wheat genome. The association analysis detected 54 haplotype loci, of which 39% contained markers with a complete reversal of allelic state. This tendency to fixation of favorable alleles corroborates the success of the Canadian durum wheat breeding programs over time. Twenty-one haplotype loci were associated with multiple traits. In particular, hap_4B_1 explained 20.6, 17.9 and 16.6% of the phenotypic variance of pigment loss, pasta b∗ and dough extensibility, respectively. The locus hap_2B_9 explained 15.9 and 17.8% of the variation of protein content and protein loss, respectively. All these pleiotropic haplotype loci offer breeders the unique opportunity for further improving multiple traits, facilitating marker-assisted selection in durum wheat, and could help in identifying genes as functional annotations of the wheat genome become available.
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Affiliation(s)
- Amidou N’Diaye
- Department of Plant Sciences, Crop Development Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Jemanesh K. Haile
- Department of Plant Sciences, Crop Development Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Kirby T. Nilsen
- Department of Plant Sciences, Crop Development Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Sean Walkowiak
- Department of Plant Sciences, Crop Development Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Yuefeng Ruan
- Agriculture and Agri-Food Canada, Swift Current Research and Development Centre, Swift Current, SK, Canada
| | - Asheesh K. Singh
- Department of Agronomy, Iowa State University, Ames, IA, United States
| | - Fran R. Clarke
- Agriculture and Agri-Food Canada, Swift Current Research and Development Centre, Swift Current, SK, Canada
| | - John M. Clarke
- Department of Plant Sciences, Crop Development Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Curtis J. Pozniak
- Department of Plant Sciences, Crop Development Centre, University of Saskatchewan, Saskatoon, SK, Canada
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36
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Markiewicz E, Idowu OC. Personalized skincare: from molecular basis to clinical and commercial applications. Clin Cosmet Investig Dermatol 2018; 11:161-171. [PMID: 29692619 PMCID: PMC5903487 DOI: 10.2147/ccid.s163799] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Individual responses of human skin to the environmental stress are determined by differences in the anatomy and physiology that are closely linked to the genetic characteristics such as pigmentation. Ethnic skin phenotypes can be distinguished based on defined genotypic traits, structural organization and compartmentalized sensitivity to distinct extrinsic aging factors. These differences are not only responsible for the variation in skin performance after exposure to damaging conditions, but can also affect the mechanisms of drug absorption, sensitization and other longer term effects. The unique characteristics of the individual skin function and, particularly, of the ethnic skin type are currently considered to shape the future of clinical and pharmacologic interventions as a basis for personalized skincare. Individual approaches to skincare render a novel and actively growing area with a range of biomedical and commercial applications within cosmetics industry. In this review, we summarize the aspects of the molecular and clinical manifestations of the environmental stress on human skin and proposed protective mechanisms that are linked to ethnic differences and pathophysiology of extrinsic skin aging. We subsequently discuss the possible applications and translation of this knowledge into personalized skincare.
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Affiliation(s)
- Ewa Markiewicz
- Research & Development, Hexis Lab, Science Central, The Core, Bath Lane, Newcastle upon Tyne, UK
| | - Olusola Clement Idowu
- Research & Development, Hexis Lab, Science Central, The Core, Bath Lane, Newcastle upon Tyne, UK
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37
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Mohd-Assaad N, McDonald BA, Croll D. Genome-Wide Detection of Genes Under Positive Selection in Worldwide Populations of the Barley Scald Pathogen. Genome Biol Evol 2018; 10:1315-1332. [PMID: 29722810 PMCID: PMC5972619 DOI: 10.1093/gbe/evy087] [Citation(s) in RCA: 22] [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] [Accepted: 04/30/2018] [Indexed: 12/29/2022] Open
Abstract
Coevolution between hosts and pathogens generates strong selection pressures to maintain resistance and infectivity, respectively. Genomes of plant pathogens often encode major effect loci for the ability to successfully infect specific host genotypes. Hence, spatial heterogeneity in host genotypes coupled with abiotic factors could lead to locally adapted pathogen populations. However, the genetic basis of local adaptation is poorly understood. Rhynchosporium commune, the pathogen causing barley scald disease, interacts at least partially in a gene-for-gene manner with its host. We analyzed global field populations of 125 R. commune isolates to identify candidate genes for local adaptation. Whole genome sequencing data showed that the pathogen is subdivided into three genetic clusters associated with distinct geographic and climatic regions. Using haplotype-based selection scans applied independently to each genetic cluster, we found strong evidence for selective sweeps throughout the genome. Comparisons of loci under selection among clusters revealed little overlap, suggesting that ecological differences associated with each cluster led to variable selection regimes. The strongest signals of selection were found predominantly in the two clusters composed of isolates from Central Europe and Ethiopia. The strongest selective sweep regions encoded protein functions related to biotic and abiotic stress responses. Selective sweep regions were enriched in genes encoding functions in cellular localization, protein transport activity, and DNA damage responses. In contrast to the prevailing view that a small number of gene-for-gene interactions govern plant pathogen evolution, our analyses suggest that the evolutionary trajectory is largely determined by spatially heterogeneous biotic and abiotic selection pressures.
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Affiliation(s)
- Norfarhan Mohd-Assaad
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Zurich, Switzerland
- School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
| | - Bruce A McDonald
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Zurich, Switzerland
| | - Daniel Croll
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, Switzerland
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38
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Putilov AA, Dorokhov VB, Poluektov MG. How have our clocks evolved? Adaptive and demographic history of the out-of-African dispersal told by polymorphic loci in circadian genes. Chronobiol Int 2017; 35:511-532. [DOI: 10.1080/07420528.2017.1417314] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Arcady A. Putilov
- Research Group for Math-Modeling of Biomedical Systems, the Research Institute for Molecular Biology and Biophysics, Novosibirsk, Russia
| | - Vladimir B. Dorokhov
- Laboratory of Sleep/Wake Neurobiology, The Institute of Higher Nervous Activity and Neurophysiology of the Russian Academy of Sciences, Moscow, Russia
| | - Michael G. Poluektov
- Department of Nervous Diseases, Institute of Professional Education, I.M. Sechenov 1-st Moscow State Medical University, Moscow, Russia
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Serres-Armero A, Povolotskaya IS, Quilez J, Ramirez O, Santpere G, Kuderna LFK, Hernandez-Rodriguez J, Fernandez-Callejo M, Gomez-Sanchez D, Freedman AH, Fan Z, Novembre J, Navarro A, Boyko A, Wayne R, Vilà C, Lorente-Galdos B, Marques-Bonet T. Similar genomic proportions of copy number variation within gray wolves and modern dog breeds inferred from whole genome sequencing. BMC Genomics 2017; 18:977. [PMID: 29258433 PMCID: PMC5735816 DOI: 10.1186/s12864-017-4318-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 11/17/2017] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Whole genome re-sequencing data from dogs and wolves are now commonly used to study how natural and artificial selection have shaped the patterns of genetic diversity. Single nucleotide polymorphisms, microsatellites and variants in mitochondrial DNA have been interrogated for links to specific phenotypes or signals of domestication. However, copy number variation (CNV), despite its increasingly recognized importance as a contributor to phenotypic diversity, has not been extensively explored in canids. RESULTS Here, we develop a new accurate probabilistic framework to create fine-scale genomic maps of segmental duplications (SDs), compare patterns of CNV across groups and investigate their role in the evolution of the domestic dog by using information from 34 canine genomes. Our analyses show that duplicated regions are enriched in genes and hence likely possess functional importance. We identify 86 loci with large CNV differences between dogs and wolves, enriched in genes responsible for sensory perception, immune response, metabolic processes, etc. In striking contrast to the observed loss of nucleotide diversity in domestic dogs following the population bottlenecks that occurred during domestication and breed creation, we find a similar proportion of CNV loci in dogs and wolves, suggesting that other dynamics are acting to particularly select for CNVs with potentially functional impacts. CONCLUSIONS This work is the first comparison of genome wide CNV patterns in domestic and wild canids using whole-genome sequencing data and our findings contribute to study the impact of novel kinds of genetic changes on the evolution of the domestic dog.
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Affiliation(s)
- Aitor Serres-Armero
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain
| | - Inna S Povolotskaya
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain
| | - Javier Quilez
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain.,CNAG-CRG, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Oscar Ramirez
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain.,Vetgenomics, 08193, Barcelona, Spain
| | - Gabriel Santpere
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain.,Department of Neuroscience, Yale School of Medicine, New Haven, CT, USA
| | - Lukas F K Kuderna
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain
| | - Jessica Hernandez-Rodriguez
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain
| | - Marcos Fernandez-Callejo
- CNAG-CRG, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Daniel Gomez-Sanchez
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain
| | - Adam H Freedman
- UCLA, Department of Ecology and Evolutionary Biology, Los Angeles, CA, 90095, USA
| | - Zhenxin Fan
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, People's Republic of China
| | - John Novembre
- UCLA, Department of Ecology and Evolutionary Biology, Los Angeles, CA, 90095, USA
| | - Arcadi Navarro
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain.,CNAG-CRG, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.,Institucio Catalana de Recerca i Estudis Avançats (ICREA), 08010, Barcelona, Catalonia, Spain
| | - Adam Boyko
- Cornell University, Department of Biological Statistics and Computational Biology, New York, NY, 14853, USA
| | - Robert Wayne
- UCLA, Department of Ecology and Evolutionary Biology, Los Angeles, CA, 90095, USA
| | - Carles Vilà
- Estación Biológica de Doñana EBD-CSIC, Department of Integrative Ecology, 41092, Sevilla, Spain
| | - Belen Lorente-Galdos
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain. .,Department of Neuroscience, Yale School of Medicine, New Haven, CT, USA.
| | - Tomas Marques-Bonet
- IBE, Institut de Biologia Evolutiva (Universitat Pompeu Fabra/CSIC), Ciencies Experimentals i de la Salut, 08003, Barcelona, Spain. .,CNAG-CRG, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain. .,Institucio Catalana de Recerca i Estudis Avançats (ICREA), 08010, Barcelona, Catalonia, Spain.
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Rawofi L, Edwards M, Krithika S, Le P, Cha D, Yang Z, Ma Y, Wang J, Su B, Jin L, Norton HL, Parra EJ. Genome-wide association study of pigmentary traits (skin and iris color) in individuals of East Asian ancestry. PeerJ 2017; 5:e3951. [PMID: 29109912 PMCID: PMC5671666 DOI: 10.7717/peerj.3951] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 10/01/2017] [Indexed: 01/08/2023] Open
Abstract
Background Currently, there is limited knowledge about the genetics underlying pigmentary traits in East Asian populations. Here, we report the results of the first genome-wide association study of pigmentary traits (skin and iris color) in individuals of East Asian ancestry. Methods We obtained quantitative skin pigmentation measures (M-index) in the inner upper arm of the participants using a portable reflectometer (N = 305). Quantitative measures of iris color (expressed as L*, a* and b* CIELab coordinates) were extracted from high-resolution iris pictures (N = 342). We also measured the color differences between the pupillary and ciliary regions of the iris (e.g., iris heterochromia). DNA samples were genotyped with Illumina’s Infinium Multi-Ethnic Global Array (MEGA) and imputed using the 1000 Genomes Phase 3 samples as reference haplotypes. Results For skin pigmentation, we did not observe any genome-wide significant signal. We followed-up in three independent Chinese samples the lead SNPs of five regions showing multiple common markers (minor allele frequency ≥ 5%) with good imputation scores and suggestive evidence of association (p-values < 10−5). One of these markers, rs2373391, which is located in an intron of the ZNF804B gene on chromosome 7, was replicated in one of the Chinese samples (p = 0.003). For iris color, we observed genome-wide signals in the OCA2 region on chromosome 15. This signal is driven by the non-synonymous rs1800414 variant, which explains 11.9%, 10.4% and 6% of the variation observed in the b*, a* and L* coordinates in our sample, respectively. However, the OCA2 region was not associated with iris heterochromia. Discussion Additional genome-wide association studies in East Asian samples will be necessary to further disentangle the genetic architecture of pigmentary traits in East Asian populations.
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Affiliation(s)
- Lida Rawofi
- Department of Anthropology, University of Toronto at Mississauga, Mississauga, Canada
| | - Melissa Edwards
- Department of Anthropology, University of Toronto at Mississauga, Mississauga, Canada
| | - S Krithika
- Department of Anthropology, University of Toronto at Mississauga, Mississauga, Canada
| | - Phuong Le
- Department of Anthropology, University of Toronto at Mississauga, Mississauga, Canada
| | - David Cha
- Department of Anthropology, University of Toronto at Mississauga, Mississauga, Canada
| | - Zhaohui Yang
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, China
| | - Yanyun Ma
- MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, Fudan University, Shanghai, China
| | - Jiucun Wang
- State Key laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Bing Su
- State Key Laboratory of Genetic Resources and Evolution, Kumming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Li Jin
- State Key laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Heather L Norton
- Department of Anthropology, University of Cincinnati, Cincinnati, United States of America
| | - Esteban J Parra
- Department of Anthropology, University of Toronto at Mississauga, Mississauga, Canada
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41
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Marciniak S, Perry GH. Harnessing ancient genomes to study the history of human adaptation. Nat Rev Genet 2017; 18:659-674. [PMID: 28890534 DOI: 10.1038/nrg.2017.65] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The past several years have witnessed an explosion of successful ancient human genome-sequencing projects, with genomic-scale ancient DNA data sets now available for more than 1,100 ancient human and archaic hominin (for example, Neandertal) individuals. Recent 'evolution in action' analyses have started using these data sets to identify and track the spatiotemporal trajectories of genetic variants associated with human adaptations to novel and changing environments, agricultural lifestyles, and introduced or co-evolving pathogens. Together with evidence of adaptive introgression of genetic variants from archaic hominins to humans and emerging ancient genome data sets for domesticated animals and plants, these studies provide novel insights into human evolution and the evolutionary consequences of human behaviour that go well beyond those that can be obtained from modern genomic data or the fossil and archaeological records alone.
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Affiliation(s)
- Stephanie Marciniak
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - George H Perry
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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42
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Deng L, Xu S. Adaptation of human skin color in various populations. Hereditas 2017; 155:1. [PMID: 28701907 PMCID: PMC5502412 DOI: 10.1186/s41065-017-0036-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 06/02/2017] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Skin color is a well-recognized adaptive trait and has been studied extensively in humans. Understanding the genetic basis of adaptation of skin color in various populations has many implications in human evolution and medicine. DISCUSSION Impressive progress has been made recently to identify genes associated with skin color variation in a wide range of geographical and temporal populations. In this review, we discuss what is currently known about the genetics of skin color variation. We enumerated several cases of skin color adaptation in global modern humans and archaic hominins, and illustrated why, when, and how skin color adaptation occurred in different populations. Finally, we provided a summary of the candidate loci associated with pigmentation, which could be a valuable reference for further evolutionary and medical studies. CONCLUSION Previous studies generally indicated a complex genetic mechanism underlying the skin color variation, expanding our understanding of the role of population demographic history and natural selection in shaping genetic and phenotypic diversity in humans. Future work is needed to dissect the genetic architecture of skin color adaptation in numerous ethnic minority groups around the world, which remains relatively obscure compared with that of major continental groups, and to unravel the exact genetic basis of skin color adaptation.
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Affiliation(s)
- Lian Deng
- Chinese Academy of Sciences (CAS) Key Laboratory of Computational Biology, Max Planck Independent Research Group on Population Genomics, CAS-MPG Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences, CAS, Shanghai, 200031 China.,University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Shuhua Xu
- Chinese Academy of Sciences (CAS) Key Laboratory of Computational Biology, Max Planck Independent Research Group on Population Genomics, CAS-MPG Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences, CAS, Shanghai, 200031 China.,University of Chinese Academy of Sciences, Beijing, 100049 China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210 China.,Collaborative Innovation Center of Genetics and Development, Shanghai, 200438 China
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Byars SG, Huang QQ, Gray LA, Bakshi A, Ripatti S, Abraham G, Stearns SC, Inouye M. Genetic loci associated with coronary artery disease harbor evidence of selection and antagonistic pleiotropy. PLoS Genet 2017; 13:e1006328. [PMID: 28640878 PMCID: PMC5480811 DOI: 10.1371/journal.pgen.1006328] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 05/02/2017] [Indexed: 12/18/2022] Open
Abstract
Traditional genome-wide scans for positive selection have mainly uncovered selective sweeps associated with monogenic traits. While selection on quantitative traits is much more common, very few signals have been detected because of their polygenic nature. We searched for positive selection signals underlying coronary artery disease (CAD) in worldwide populations, using novel approaches to quantify relationships between polygenic selection signals and CAD genetic risk. We identified new candidate adaptive loci that appear to have been directly modified by disease pressures given their significant associations with CAD genetic risk. These candidates were all uniquely and consistently associated with many different male and female reproductive traits suggesting selection may have also targeted these because of their direct effects on fitness. We found that CAD loci are significantly enriched for lifetime reproductive success relative to the rest of the human genome, with evidence that the relationship between CAD and lifetime reproductive success is antagonistic. This supports the presence of antagonistic-pleiotropic tradeoffs on CAD loci and provides a novel explanation for the maintenance and high prevalence of CAD in modern humans. Lastly, we found that positive selection more often targeted CAD gene regulatory variants using HapMap3 lymphoblastoid cell lines, which further highlights the unique biological significance of candidate adaptive loci underlying CAD. Our study provides a novel approach for detecting selection on polygenic traits and evidence that modern human genomes have evolved in response to CAD-induced selection pressures and other early-life traits sharing pleiotropic links with CAD.
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Affiliation(s)
- Sean G. Byars
- Centre for Systems Genomics, School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Qin Qin Huang
- Centre for Systems Genomics, School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Lesley-Ann Gray
- Centre for Systems Genomics, School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Andrew Bakshi
- Centre for Systems Genomics, School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Samuli Ripatti
- Institute of Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
- Department of Public Health, University of Helsinki, Helsinki, Finland
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Gad Abraham
- Centre for Systems Genomics, School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Stephen C. Stearns
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, United States of America
| | - Michael Inouye
- Centre for Systems Genomics, School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
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Walsh S, Chaitanya L, Breslin K, Muralidharan C, Bronikowska A, Pospiech E, Koller J, Kovatsi L, Wollstein A, Branicki W, Liu F, Kayser M. Global skin colour prediction from DNA. Hum Genet 2017; 136:847-863. [PMID: 28500464 PMCID: PMC5487854 DOI: 10.1007/s00439-017-1808-5] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 05/03/2017] [Indexed: 12/14/2022]
Abstract
Human skin colour is highly heritable and externally visible with relevance in medical, forensic, and anthropological genetics. Although eye and hair colour can already be predicted with high accuracies from small sets of carefully selected DNA markers, knowledge about the genetic predictability of skin colour is limited. Here, we investigate the skin colour predictive value of 77 single-nucleotide polymorphisms (SNPs) from 37 genetic loci previously associated with human pigmentation using 2025 individuals from 31 global populations. We identified a minimal set of 36 highly informative skin colour predictive SNPs and developed a statistical prediction model capable of skin colour prediction on a global scale. Average cross-validated prediction accuracies expressed as area under the receiver-operating characteristic curve (AUC) ± standard deviation were 0.97 ± 0.02 for Light, 0.83 ± 0.11 for Dark, and 0.96 ± 0.03 for Dark-Black. When using a 5-category, this resulted in 0.74 ± 0.05 for Very Pale, 0.72 ± 0.03 for Pale, 0.73 ± 0.03 for Intermediate, 0.87±0.1 for Dark, and 0.97 ± 0.03 for Dark-Black. A comparative analysis in 194 independent samples from 17 populations demonstrated that our model outperformed a previously proposed 10-SNP-classifier approach with AUCs rising from 0.79 to 0.82 for White, comparable at the intermediate level of 0.63 and 0.62, respectively, and a large increase from 0.64 to 0.92 for Black. Overall, this study demonstrates that the chosen DNA markers and prediction model, particularly the 5-category level; allow skin colour predictions within and between continental regions for the first time, which will serve as a valuable resource for future applications in forensic and anthropologic genetics.
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Affiliation(s)
- Susan Walsh
- Department of Biology, Indiana University Purdue University Indianapolis (IUPUI), Indianapolis, IN, USA.
| | - Lakshmi Chaitanya
- Department of Genetic Identification, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Krystal Breslin
- Department of Biology, Indiana University Purdue University Indianapolis (IUPUI), Indianapolis, IN, USA
| | - Charanya Muralidharan
- Department of Biology, Indiana University Purdue University Indianapolis (IUPUI), Indianapolis, IN, USA
| | - Agnieszka Bronikowska
- Department of Dermatology, Collegium Medicum of the Jagiellonian University, Kraków, Poland
| | - Ewelina Pospiech
- Faculty of Biology and Earth Sciences, Institute of Zoology, Jagiellonian University, Kraków, Poland
- Malopolska Centre of Biotechnology, Jagiellonian University, Kraków, Poland
| | - Julia Koller
- Department of Genetic Identification, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Leda Kovatsi
- Laboratory of Forensic Medicine and Toxicology, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Andreas Wollstein
- Section of Evolutionary Biology, Department of Biology II, University of Munich LMU, Planegg-Martinsried, Germany
| | - Wojciech Branicki
- Malopolska Centre of Biotechnology, Jagiellonian University, Kraków, Poland
- Central Forensic Laboratory of the Police, Warsaw, Poland
| | - Fan Liu
- Department of Genetic Identification, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands
- Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Manfred Kayser
- Department of Genetic Identification, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands.
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Jonnalagadda M, Bharti N, Patil Y, Ozarkar S, K SM, Joshi R, Norton H. Identifying signatures of positive selection in pigmentation genes in two South Asian populations. Am J Hum Biol 2017; 29. [PMID: 28439965 DOI: 10.1002/ajhb.23012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/14/2017] [Accepted: 04/01/2017] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVES Skin pigmentation is a polygenic trait showing wide phenotypic variations among global populations. While numerous pigmentation genes have been identified to be under positive selection among European and East populations, genes contributing to phenotypic variation in skin pigmentation within and among South Asian populations are still poorly understood. The present study uses data from the Phase 3 of the 1000 genomes project focusing on two South Asian populations-GIH (Gujarati Indian from Houston, Texas) and ITU (Indian Telugu from UK), so as to decode the genetic architecture involved in adaptation to ultraviolet radiation in South Asian populations. METHODS Statistical tests included were (1) tests to identify deviations of the Site Frequency Spectrum (SFS) from neutral expectations (Tajima's D, Fay and Wu's H and Fu and Li's D* and F*), (2) tests focused on the identification of high-frequency haplotypes with extended linkage disequilibrium (iHS and Rsb), and (3) tests based on genetic differentiation between populations (LSBL). RESULTS Twenty-two pigmentation genes fall in the top 1% for at least one statistic in the GIH population, 5 of which (LYST, OCA2, SLC24A5, SLC45A2, and TYR) have been previously associated with normal variation in skin, hair, or eye color. In comparison, 17 genes fall in the top 1% for at least one statistic in the ITU population. Twelve loci which are identified as outliers in the ITU scan were also identified in the GIH population. CONCLUSIONS These results suggest that selection may have affected these loci broadly across the region.
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Affiliation(s)
- Manjari Jonnalagadda
- Symbiosis School for Liberal Arts (SSLA), Symbiosis International University (SIU), Pune, 411014, India
| | - Neeraj Bharti
- HPC-MBA Group, Centre for Development of Advanced Computing, Pune, 411007, India
| | - Yatish Patil
- HPC-MBA Group, Centre for Development of Advanced Computing, Pune, 411007, India
| | - Shantanu Ozarkar
- Department of Anthropology, Savitribai Phule Pune University, Pune, 411007, India
| | - Sunitha Manjari K
- HPC-MBA Group, Centre for Development of Advanced Computing, Pune, 411007, India
| | - Rajendra Joshi
- HPC-MBA Group, Centre for Development of Advanced Computing, Pune, 411007, India
| | - Heather Norton
- Department of Anthropology, University of Cincinnati, Cincinnati, Ohio
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Wakamatsu K, Nagao A, Watanabe M, Nakao K, Ito S. Pheomelanogenesis is promoted at a weakly acidic pH. Pigment Cell Melanoma Res 2017; 30:372-377. [PMID: 28271633 DOI: 10.1111/pcmr.12587] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 02/28/2017] [Indexed: 11/29/2022]
Abstract
The diversity of pigmentation in the skin, hair, and eyes of humans has been largely attributed to the diversity of pH in melanosomes with an acidic pH being proposed to suppress melanin production, especially eumelanogenesis. We previously showed that an acidic pH greatly suppresses the late stage of eumelanogenesis after the dopachrome stage. The oxidation of tyrosine by tyrosinase in the presence of cysteine forms cysteinyldopa isomers, which are further oxidized to give rise to pheomelanin via benzothiazine intermediates. However, how those steps are controlled by pH has not been characterized. We therefore examined whether pheomelanin synthesis is chemically promoted at an acidic pH. We found that pheomelanin production either from dopa or tyrosine in the presence of cysteine by tyrosinase was greatest at pH values of 5.8-6.3, while eumelanin production was suppressed at pH 5.8. This suggests that mixed melanogenesis is chemically shifted to more pheomelanic states at a weakly acidic pH.
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Affiliation(s)
- Kazumasa Wakamatsu
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, Japan
| | - Ayano Nagao
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, Japan
| | - Miu Watanabe
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, Japan
| | - Kenta Nakao
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, Japan
| | - Shosuke Ito
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, Japan
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D'Elia MPB, Brandão MC, de Andrade Ramos BR, da Silva MG, Miot LDB, Dos Santos SEB, Miot HA. African ancestry is associated with facial melasma in women: a cross-sectional study. BMC MEDICAL GENETICS 2017; 18:17. [PMID: 28212612 PMCID: PMC5316149 DOI: 10.1186/s12881-017-0378-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 02/03/2017] [Indexed: 12/20/2022]
Abstract
Background Melasma is a chronic acquired focal hypermelanosis affecting photoexposed areas, especially for women during fertile age. Several factors contribute to its development: sun exposure, sex steroids, medicines, and family history. Melanic pigmentation pathway discloses several SNPs in different populations. Here, we evaluated the association between genetic ancestry and facial melasma. Methods A cross-sectional study involving women with melasma and an age-matched control group from outpatients at FMB-Unesp, Botucatu-SP, Brazil was performed. DNA was extracted from oral mucosa swabs and ancestry determined by studying 61 INDELs. The genetic ancestry components were adjusted by other known risk factors by multiple logistic regression. Results We evaluated 119 women with facial melasma and 119 controls. Mean age was 39 ± 9 years. Mean age at beginning of disease was 27 ± 8 years. Pregnancy (40%), sun exposure (37%), and hormonal oral contraception (22%) were the most frequently reported melasma triggers. All subjects presented admixed ancestry, African and European genetic contributions were significantly different between cases and controls (respectively 10% vs 6%; 77% vs 82%; p < 0.05). African ancestry (OR = 1.04; 95% CI 1.01 to 1.07), first generation family history (OR = 3.04; 95% CI 1.56 to 5.94), low education level (OR = 4.04; 95% CI 1.56 to 5.94), and use of antidepressants by individuals with affected family members (OR = 6.15; 95% CI 1.13 to 33.37) were associated with melasma, independently of other known risk factors. Conclusions Facial melasma was independently associated with African ancestry in a highly admixed population. Electronic supplementary material The online version of this article (doi:10.1186/s12881-017-0378-7) contains supplementary material, which is available to authorized users.
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Mishra A, Nizammuddin S, Mallick CB, Singh S, Prakash S, Siddiqui NA, Rai N, Carlus SJ, Sudhakar DVS, Tripathi VP, Möls M, Kim-Howard X, Dewangan H, Mishra A, Reddy AG, Roy B, Pandey K, Chaubey G, Das P, Nath SK, Singh L, Thangaraj K. Genotype-Phenotype Study of the Middle Gangetic Plain in India Shows Association of rs2470102 with Skin Pigmentation. J Invest Dermatol 2016; 137:670-677. [PMID: 27866970 DOI: 10.1016/j.jid.2016.10.043] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 10/15/2016] [Accepted: 10/17/2016] [Indexed: 02/06/2023]
Abstract
Our understanding of the genetics of skin pigmentation has been largely skewed towards populations of European ancestry, imparting less attention to South Asian populations, who behold huge pigmentation diversity. Here, we investigate skin pigmentation variation in a cohort of 1,167 individuals in the Middle Gangetic Plain of the Indian subcontinent. Our data confirm the association of rs1426654 with skin pigmentation among South Asians, consistent with previous studies, and also show association for rs2470102 single nucleotide polymorphism. Our haplotype analyses further help us delineate the haplotype distribution across social categories and skin color. Taken together, our findings suggest that the social structure defined by the caste system in India has a profound influence on the skin pigmentation patterns of the subcontinent. In particular, social category and associated single nucleotide polymorphisms explain about 32% and 6.4%, respectively, of the total phenotypic variance. Phylogeography of the associated single nucleotide polymorphisms studied across 52 diverse populations of the Indian subcontinent shows wide presence of the derived alleles, although their frequencies vary across populations. Our results show that both polymorphisms (rs1426654 and rs2470102) play an important role in the skin pigmentation diversity of South Asians.
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Affiliation(s)
- Anshuman Mishra
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | - Chandana Basu Mallick
- Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia; Estonian Biocentre, Tartu, Estonia
| | - Sakshi Singh
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Satya Prakash
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | - Niraj Rai
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - S Justin Carlus
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | - Vishnu P Tripathi
- Department of Biotechnology, V.B.S. Purvanchal University, Jaunpur, India
| | - Märt Möls
- Estonian Biocentre, Tartu, Estonia; Insitute of Mathematical Statistics, University of Tartu, Tartu, Estonia
| | - Xana Kim-Howard
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma, USA
| | | | | | - Alla G Reddy
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Biswajit Roy
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Krishna Pandey
- Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | | | - Pradeep Das
- Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Swapan K Nath
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma, USA
| | - Lalji Singh
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
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Domyan ET, Shapiro MD. Pigeonetics takes flight: Evolution, development, and genetics of intraspecific variation. Dev Biol 2016; 427:241-250. [PMID: 27847323 DOI: 10.1016/j.ydbio.2016.11.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 10/28/2016] [Accepted: 11/10/2016] [Indexed: 11/26/2022]
Abstract
Intensive artificial selection over thousands of years has produced hundreds of varieties of domestic pigeon. As Charles Darwin observed, the morphological differences among breeds can rise to the magnitude of variation typically observed among different species. Nevertheless, different pigeon varieties are interfertile, thereby enabling forward genetic and genomic approaches to identify genes that underlie derived traits. Building on classical genetic studies of pigeon variation, recent molecular investigations find a spectrum of coding and regulatory alleles controlling derived traits, including plumage color, feather growth polarity, and limb identity. Developmental and genetic analyses of pigeons are revealing the molecular basis of variation in a classic example of extreme intraspecific diversity, and have the potential to nominate genes that control variation among other birds and vertebrates in general.
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Affiliation(s)
- Eric T Domyan
- Department of Biology, Utah Valley University, Orem, UT, United States.
| | - Michael D Shapiro
- Department of Biology, University of Utah, Salt Lake City, UT, United States.
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50
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Field Y, Boyle EA, Telis N, Gao Z, Gaulton KJ, Golan D, Yengo L, Rocheleau G, Froguel P, McCarthy MI, Pritchard JK. Detection of human adaptation during the past 2000 years. Science 2016; 354:760-764. [PMID: 27738015 PMCID: PMC5182071 DOI: 10.1126/science.aag0776] [Citation(s) in RCA: 234] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 10/03/2016] [Indexed: 12/22/2022]
Abstract
Detection of recent natural selection is a challenging problem in population genetics. Here we introduce the singleton density score (SDS), a method to infer very recent changes in allele frequencies from contemporary genome sequences. Applied to data from the UK10K Project, SDS reflects allele frequency changes in the ancestors of modern Britons during the past ~2000 to 3000 years. We see strong signals of selection at lactase and the major histocompatibility complex, and in favor of blond hair and blue eyes. For polygenic adaptation, we find that recent selection for increased height has driven allele frequency shifts across most of the genome. Moreover, we identify shifts associated with other complex traits, suggesting that polygenic adaptation has played a pervasive role in shaping genotypic and phenotypic variation in modern humans.
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Affiliation(s)
- Yair Field
- Department of Genetics, Stanford University, Stanford, CA 94305, USA.
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
| | - Evan A Boyle
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Natalie Telis
- Program in Biomedical Informatics, Stanford University, Stanford, CA 94305, USA
| | - Ziyue Gao
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
| | - Kyle J Gaulton
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
- Wellcome Trust Center for Human Genetics, and Oxford Center for Diabetes Endocrinology and Metabolism, University of Oxford, Oxford, UK
| | - David Golan
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Loic Yengo
- Univ. Lille, CNRS, Institut Pasteur de Lille, UMR 8199-EGID, F-59000 Lille, France
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Ghislain Rocheleau
- Univ. Lille, CNRS, Institut Pasteur de Lille, UMR 8199-EGID, F-59000 Lille, France
| | - Philippe Froguel
- Univ. Lille, CNRS, Institut Pasteur de Lille, UMR 8199-EGID, F-59000 Lille, France
- Imperial College, Department of Genomics of Common Disease, London Hammersmith Hospital, London, UK
| | - Mark I McCarthy
- Wellcome Trust Center for Human Genetics, and Oxford Center for Diabetes Endocrinology and Metabolism, University of Oxford, Oxford, UK
| | - Jonathan K Pritchard
- Department of Genetics, Stanford University, Stanford, CA 94305, USA.
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
- Department of Biology, Stanford University, Stanford, CA, USA
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