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Bharti N, Banerjee R, Achalare A, Kasibhatla SM, Joshi R. Estimation of genetic variation in vitiligo associated genes: Population genomics perspective. BMC Genom Data 2024; 25:72. [PMID: 39060965 PMCID: PMC11282599 DOI: 10.1186/s12863-024-01254-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND Vitiligo is an auto-immune progressive depigmentation disorder of the skin due to loss of melanocytes. Genetic risk is one of the important factors for development of vitiligo. Preponderance of vitiligo in certain ethnicities is known which can be analysed by understanding the distribution of allele frequencies across normal populations. Earlier GWAS identified 108 risk alleles for vitiligo in Europeans and East Asians. In this study, 64 of these risk alleles were used for analysing their enrichment and depletion across populations (1000 Genomes Project and IndiGen) with reference to 1000 Genomes dataset. Genetic risk scores were calculated and Fisher's exact test was performed to understand statistical significance of their variation in each population with respect to 1000 Genomes dataset as reference. In addition to SNPs reported in GWAS, significant variation in allele frequencies of 1079 vitiligo-related genes were also analysed. Two-tailed Chi-square test and Bonferroni's multiple adjustment values along with fixation index (≥ 0.5) and minimum allele frequency (≥ 0.05) were calculated and used to prioritise the variants based on pairwise comparison across populations. RESULTS Risk alleles rs1043101 and rs10768122 belong to 3 prime UTR of glutamate receptor gene SLC1A2 are found to be highly enriched in the South Asian population when compared with the 'global normal' population. Intron variant rs4766578 (ATXN2) was found to be deleted in SAS, EAS and AFR and enriched in EUR and AMR1. This risk allele is found to be under positive selection in SAS, AMR1 and EUR. From the ancillary vitiligo gene list, nonsynonymous variant rs16891982 was found to be enriched in the European and the Admixed American populations and depleted in all others. rs2279238 and rs11039155 belonging to the LXR-α gene involved in regulation of metalloproteinase 2 and 9 (melanocyte precursors) were found to be associated with vitiligo in the North Indian population (in earlier study). CONCLUSION The differential enrichment/depletion profile of the risk alleles provides insight into the underlying inter-population variations. This would provide clues towards prioritisation of SNPs associated with vitiligo thereby elucidating its preponderance in different ethnic groups.
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Affiliation(s)
- Neeraj Bharti
- HPC-Medical and Bioinformatics Applications Group, Centre for Development of Advanced Computing, Innovation Park, Pashan, Pune, 411008, Maharashtra, India
| | - Ruma Banerjee
- HPC-Medical and Bioinformatics Applications Group, Centre for Development of Advanced Computing, Innovation Park, Pashan, Pune, 411008, Maharashtra, India
| | - Archana Achalare
- HPC-Medical and Bioinformatics Applications Group, Centre for Development of Advanced Computing, Innovation Park, Pashan, Pune, 411008, Maharashtra, India
| | - Sunitha Manjari Kasibhatla
- HPC-Medical and Bioinformatics Applications Group, Centre for Development of Advanced Computing, Innovation Park, Pashan, Pune, 411008, Maharashtra, India
| | - Rajendra Joshi
- HPC-Medical and Bioinformatics Applications Group, Centre for Development of Advanced Computing, Innovation Park, Pashan, Pune, 411008, Maharashtra, India.
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Davoudi P, Do DN, Rathgeber B, Colombo S, Sargolzaei M, Plastow G, Wang Z, Miar Y. Characterization of runs of homozygosity islands in American mink using whole-genome sequencing data. J Anim Breed Genet 2024. [PMID: 38389405 DOI: 10.1111/jbg.12859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/27/2024] [Accepted: 02/02/2024] [Indexed: 02/24/2024]
Abstract
The genome-wide analysis of runs of homozygosity (ROH) islands can be an effective strategy for identifying shared variants within a population and uncovering important genomic regions related to complex traits. The current study performed ROH analysis to characterize the genome-wide patterns of homozygosity, identify ROH islands and annotated genes within these candidate regions using whole-genome sequencing data from 100 American mink (Neogale vison). After sequence processing, variants were called using GATK and Samtools pipelines. Subsequent to quality control, 8,373,854 bi-allelic variants identified by both pipelines remained for further analysis. A total of 34,652 ROH segments were identified in all individuals, among which shorter segments (0.3-1 Mb) were abundant throughout the genome, approximately accounting for 84.39% of all ROH. Within these segments, we identified 63 ROH islands housing 156 annotated genes. The genes located in ROH islands were associated with fur quality (EDNRA, FGF2, FOXA2 and SLC24A4), body size/weight (MYLK4, PRIM2, FABP2, EYS and PHF3), immune capacity (IL2, IL21, PTP4A1, SEMA4C, JAK2, CCNA2 and TNIP3) and reproduction (ADAD1, KHDRBS2, INSL6, PGRMC2 and HSPA4L). Furthermore, Gene Ontology and KEGG pathway enrichment analyses revealed 56 and 9 significant terms (FDR-corrected p-value < 0.05), respectively, among which cGMP-PKG signalling pathway, regulation of actin cytoskeleton, and calcium signalling pathway were highlighted due to their functional roles in growth and fur characteristics. This is the first study to present ROH islands in American mink. The candidate genes from ROH islands and functional enrichment analysis suggest possible signatures of selection in response to the mink breeding targets, such as increased body length, reproductive performance and fur quality. These findings contribute to our understanding of genetic characteristics, and provide complementary information to assist with implementation of breeding strategies for genetic improvement in American mink.
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Affiliation(s)
- Pourya Davoudi
- Department of Animal Science and Aquaculture, Dalhousie University, Truro, Nova Scotia, Canada
| | - Duy Ngoc Do
- Department of Animal Science and Aquaculture, Dalhousie University, Truro, Nova Scotia, Canada
| | - Bruce Rathgeber
- Department of Animal Science and Aquaculture, Dalhousie University, Truro, Nova Scotia, Canada
| | - Stefanie Colombo
- Department of Animal Science and Aquaculture, Dalhousie University, Truro, Nova Scotia, Canada
| | - Mehdi Sargolzaei
- Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada
- Select Sires Inc., Plain City, Ohio, USA
| | - Graham Plastow
- Livestock Gentec, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Zhiquan Wang
- Livestock Gentec, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Younes Miar
- Department of Animal Science and Aquaculture, Dalhousie University, Truro, Nova Scotia, Canada
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Emani PS, Geradi MN, Gürsoy G, Grasty MR, Miranker A, Gerstein MB. Assessing and mitigating privacy risks of sparse, noisy genotypes by local alignment to haplotype databases. Genome Res 2023; 33:2156-2173. [PMID: 38097386 PMCID: PMC10760520 DOI: 10.1101/gr.278322.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 11/18/2023] [Indexed: 01/04/2024]
Abstract
Single nucleotide polymorphisms (SNPs) from omics data create a reidentification risk for individuals and their relatives. Although the ability of thousands of SNPs (especially rare ones) to identify individuals has been repeatedly shown, the availability of small sets of noisy genotypes, from environmental DNA samples or functional genomics data, motivated us to quantify their informativeness. We present a computational tool suite, termed Privacy Leakage by Inference across Genotypic HMM Trajectories (PLIGHT), using population-genetics-based hidden Markov models (HMMs) of recombination and mutation to find piecewise alignment of small, noisy SNP sets to reference haplotype databases. We explore cases in which query individuals are either known to be in the database, or not, and consider several genotype queries, including those from environmental sample swabs from known individuals and from simulated "mosaics" (two-individual composites). Using PLIGHT on a database with ∼5000 haplotypes, we find for common, noise-free SNPs that only ten are sufficient to identify individuals, ∼20 can identify both components in two-individual mosaics, and 20-30 can identify first-order relatives. Using noisy environmental-sample-derived SNPs, PLIGHT identifies individuals in a database using ∼30 SNPs. Even when the individuals are not in the database, local genotype matches allow for some phenotypic information leakage based on coarse-grained SNP imputation. Finally, by quantifying privacy leakage from sparse SNP sets, PLIGHT helps determine the value of selectively sanitizing released SNPs without explicit assumptions about population membership or allele frequency. To make this practical, we provide a sanitization tool to remove the most identifying SNPs from genomic data.
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Affiliation(s)
- Prashant S Emani
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Maya N Geradi
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Gamze Gürsoy
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Monica R Grasty
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Andrew Miranker
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Mark B Gerstein
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520, USA;
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA
- Department of Computer Science, Yale University, New Haven, Connecticut 06520, USA
- Department of Statistics and Data Science, Yale University, New Haven, Connecticut 06520, USA
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Brancato D, Coniglio E, Bruno F, Agostini V, Saccone S, Federico C. Forensic DNA Phenotyping: Genes and Genetic Variants for Eye Color Prediction. Genes (Basel) 2023; 14:1604. [PMID: 37628655 PMCID: PMC10454093 DOI: 10.3390/genes14081604] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/31/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
In recent decades, the use of genetic polymorphisms related to specific phenotypes, such as eye color, has greatly contributed to the development of the research field called forensic DNA phenotyping (FDP), enabling the investigators of crime cases to reduce the number of suspects, making their work faster and more precise. Eye color is a polygenic phenotype, and many genetic variants have been highlighted, with the major contributor being the HERC2-OCA2 locus, where many single nucleotide variations (SNPs) were identified. Interestingly, the HERC2-OCA2 locus, containing the intronic SNP rs12913832, the major eye color determinant, shows a high level of evolutionary conservation across many species of vertebrates. Currently, there are some genetic panels to predict eye color by genomic DNA analysis, even if the exact role of the SNP variants in the formation of eye color is still poorly understood, with a low level of predictivity in the so-called intermediate eye color. Many variants in OCA2, HERC2, and other genes lie in introns or correspond to synonymous variants, highlighting greater complexity in the mechanism of action of such genes than a simple missense variation. Here, we show the main genes involved in oculocutaneous pigmentation and their structural and functional features, as well as which genetic variants show the highest level of eye color predictivity in currently used FDP assays. Despite the great recent advances and impact of FDP in criminal cases, it is necessary to enhance scientific research to better understand the mechanism of action behind each genetic variant involved in eye color, with the goal of obtaining higher levels of prediction.
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Affiliation(s)
- Desiree Brancato
- Department Biological, Geological, Environmental Sciences, University of Catania, Via Androne 81, 95124 Catania, Italy; (D.B.); (E.C.); (F.B.); (C.F.)
| | - Elvira Coniglio
- Department Biological, Geological, Environmental Sciences, University of Catania, Via Androne 81, 95124 Catania, Italy; (D.B.); (E.C.); (F.B.); (C.F.)
| | - Francesca Bruno
- Department Biological, Geological, Environmental Sciences, University of Catania, Via Androne 81, 95124 Catania, Italy; (D.B.); (E.C.); (F.B.); (C.F.)
| | - Vincenzo Agostini
- Department Science and Technical Innovation, University of Eastern Piedmont, Viale Teresa Michel 11, 15121 Alessandria, Italy;
| | - Salvatore Saccone
- Department Biological, Geological, Environmental Sciences, University of Catania, Via Androne 81, 95124 Catania, Italy; (D.B.); (E.C.); (F.B.); (C.F.)
| | - Concetta Federico
- Department Biological, Geological, Environmental Sciences, University of Catania, Via Androne 81, 95124 Catania, Italy; (D.B.); (E.C.); (F.B.); (C.F.)
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Rahat MA, Akbar F, Rasool A, Ilyas M, Rakha A, Shams S, Jelani M, Bibi F, Shirah BH, Abdulkareem AA, Naseer MI, Israr M. Phenotypic Classification of Eye Colour and Developmental Validation of the Irisplex System on Population Living in Malakand Division, Pakistan. Biomedicines 2023; 11:biomedicines11041228. [PMID: 37189847 DOI: 10.3390/biomedicines11041228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 05/17/2023] Open
Abstract
The core objective of forensic DNA typing is developing DNA profiles from biological evidence for personal identification. The present study was designed to check the validation of the IrisPlex system and the Prevalence of eye colour in the Pakhtoon population residing within the Malakand Division. METHODS Eye colour digital photographs and buccal swab samples of 893 individuals of different age groups were collected. Multiplexed SNaPshot single base extension chemistry was used, and the genotypic results were analysed. Snapshot data were used for eye colour prediction through the IrisPlex and FROG-kb tool. RESULTS The results of the present study found brown eye colour to be the most prevalent eye colour in comparison to intermediate and blue coloured. Overall, individuals with brown-coloured eyes possess CT (46.84%) and TT (53.16%) genotypes. Blue eye-coloured individuals are solely of the CC genotype, while individuals of intermediate eye colour carry CT (45.15%) and CC (53.85%) genotypes in rs12913832 SNP in the HERC2 gene. It was also revealed that brown-coloured eyes individuals were dominant among all age groups followed by intermediate and blue. Statistical analysis between particular variables and eye colour showed a significant p-value (<0.05) for rs16891982 SNP in SLC45A2 gene, rs12913832 SNP in HERC2 gene, rs1393350 SNP in SLC45A2, districts and gender. The rest of the SNPs were non-significant with eye colour, respectively. The rs12896399 SNP and SNP rs1800407 were found significant with rs16891982 SNP. The result also demonstrated that the study group differs from the world population based on eye colour. The two eye colour prediction results were compared, and it was discovered that IrisPlex and FROG-Kb had similar higher prediction ratios for Brown and Blue eye colour. CONCLUSIONS The results of the current study revealed brown eye colour to be the most prevalent amongst members of the local population of Pakhtoon ethnicity in the Malakand Division of northern Pakistan. A set of contemporary human DNA samples with known phenotypes are used in this research to evaluate the custom panel's prediction accuracy. With the aid of this forensic test, DNA typing can be supplemented with details about the appearance of the person from whom the sample was taken in cases involving missing persons, ancient human remains, and trace samples. This study may be helpful for future population genetics and forensics studies.
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Affiliation(s)
- Murad Ali Rahat
- Centre for Biotechnology and Microbiology, University of Swat, Charbagh 19120, Pakistan
- Department of Forensic Sciences, University of Swat, Charbagh 19120, Pakistan
| | - Fazal Akbar
- Centre for Biotechnology and Microbiology, University of Swat, Charbagh 19120, Pakistan
| | - Akhtar Rasool
- Centre for Biotechnology and Microbiology, University of Swat, Charbagh 19120, Pakistan
| | - Muhammad Ilyas
- Centre for Omic Sciences, Islamia College University Peshawar, Peshawar 25120, Pakistan
| | - Allah Rakha
- Department of Forensic Sciences, University of Health Sciences, Lahore 54600, Pakistan
| | - Sulaiman Shams
- Department of Biochemistry, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan
| | - Musharraf Jelani
- Centre for Omic Sciences, Islamia College University Peshawar, Peshawar 25120, Pakistan
| | - Fehmida Bibi
- Special Infectious Agents Unit, King Fahd Medical Research Centre, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Bader H Shirah
- Department of Neuroscience, King Faisal Specialist Hospital & Research Centre, Jeddah 21589, Saudi Arabia
| | - Angham Abdulrhman Abdulkareem
- Faculty of Science, Department of Biochemistry, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Muhammad Imran Naseer
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Muhammad Israr
- Department of Forensic Sciences, University of Swat, Charbagh 19120, Pakistan
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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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Assessing effectiveness of many-objective evolutionary algorithms for selection of tag SNPs. PLoS One 2022; 17:e0278560. [PMID: 36480538 PMCID: PMC9731481 DOI: 10.1371/journal.pone.0278560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 11/19/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Studies on genome-wide associations help to determine the cause of many genetic diseases. Genome-wide associations typically focus on associations between single-nucleotide polymorphisms (SNPs). Genotyping every SNP in a chromosomal region for identifying genetic variation is computationally very expensive. A representative subset of SNPs, called tag SNPs, can be used to identify genetic variation. Small tag SNPs save the computation time of genotyping platform, however, there could be missing data or genotyping errors in small tag SNPs. This study aims to solve Tag SNPs selection problem using many-objective evolutionary algorithms. METHODS Tag SNPs selection can be viewed as an optimization problem with some trade-offs between objectives, e.g. minimizing the number of tag SNPs and maximizing tolerance for missing data. In this study, the tag SNPs selection problem is formulated as a many-objective problem. Nondominated Sorting based Genetic Algorithm (NSGA-III), and Multi-Objective Evolutionary Algorithm based on Decomposition (MOEA/D), which are Many-Objective evolutionary algorithms, have been applied and investigated for optimal tag SNPs selection. This study also investigates different initialization methods like greedy and random initialization. optimization. RESULTS The evaluation measures used for comparing results for different algorithms are Hypervolume, Range, SumMin, MinSum, Tolerance rate, and Average Hamming distance. Overall MOEA/D algorithm gives superior results as compared to other algorithms in most cases. NSGA-III outperforms NSGA-II and other compared algorithms on maximum tolerance rate, and SPEA2 outperforms all algorithms on average hamming distance. CONCLUSION Experimental results show that the performance of our proposed many-objective algorithms is much superior as compared to the results of existing methods. The outcomes show the advantages of greedy initialization over random initialization using NSGA-III, SPEA2, and MOEA/D to solve the tag SNPs selection as many-objective optimization problem.
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Investigating the genetic architecture of eye colour in a Canadian cohort. iScience 2022; 25:104485. [PMID: 35712076 PMCID: PMC9194134 DOI: 10.1016/j.isci.2022.104485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 04/18/2022] [Accepted: 05/24/2022] [Indexed: 11/24/2022] Open
Abstract
Eye color is highly variable in populations with European ancestry, ranging from low to high quantities of melanin in the iris. Polymorphisms in the HERC2/OCA2 locus have the largest effect on eye color in these populations, although other genomic regions also influence eye color. We performed genome-wide association studies of eye color in a Canadian cohort of European ancestry (N = 5,641) and investigated candidate causal variants. We uncovered several candidate causal signals in the HERC2/OCA2 region, whereas other loci likely harbor a single causal signal. We observed colocalization of eye color signals with the expression or methylation profiles of cultured primary melanocytes. Genetic correlations of eye and hair color suggest high genome-wide pleiotropy, but locus-level differences in the genetic architecture of both traits. Overall, we provide a better picture of the polymorphisms underpinning eye color variation, which may be a consequence of specific molecular processes in the iris melanocytes. Genome-wide association studies of eye color in 5,641 participants Multiple independent candidate causal variants were identified across HERC2/OCA2 Single candidate causal variants observed on or near IRF4, SLC24A4, TYR, and TYRP1 Colocalization of eye color signals with expression and methylation profiles
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Predicting eye and hair colour in a Norwegian population using Verogen's ForenSeq™ DNA signature prep kit. Forensic Sci Int Genet 2021; 56:102620. [PMID: 34735941 DOI: 10.1016/j.fsigen.2021.102620] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 09/24/2021] [Accepted: 10/21/2021] [Indexed: 01/01/2023]
Abstract
Prediction of eye and hair colour from DNA can be an important investigative tool in forensic cases if conventional DNA profiling fails to match DNA from any known suspects or cannot obtain a hit in a DNA database. The HIrisPlex model for simultaneous eye and hair colour predictions was developed for forensic usage. To genotype a DNA sample, massively parallel sequencing (MPS) has brought new possibilities to the analysis of forensic DNA samples. As part of an in-house validation, this study presents the genotyping and predictive performance of the HIrisPlex SNPs in a Norwegian study population, using Verogen's ForenSeq™ DNA Signature Prep Kit on the MiSeq FGx system and the HIrisPlex webtool. DNA-profiles were successfully typed with DNA input down to 125 pg. In samples with DNA input < 125 pg, false homozygotes were observed with as many as 92 reads. Prediction accuracies in terms of AUC were high for red (0.97) and black (0.93) hair colours, as well as blue (0.85) and brown (0.94) eye colours. The AUCs for blond (0.72) and brown (0.70) hair colour were considerably lower. None of the individuals was predicted to have intermediate eye colour. Therefore, the error rates of the overall eye colour predictions were 37% with no predictive probability threshold (pmax) and 26% with a probability threshold of 0.7. We also observed that more than half of the incorrect predictions were for individuals carrying the rs12913832 GG genotype. For hair colour, 65% of the individuals were correctly predicted when using the highest probability category approach. The main error was observed for individuals with brown hair colour that were predicted to have blond hair. Utilising the prediction guide approach increased the correct predictions to 75%. Assessment of phenotype-genotype associations of eye colours using a quantitative eye colour score (PIE-score), revealed that rs12913832 AA individuals of Norwegian descent had statistically significantly higher PIE-score (less brown eye colour) than individuals of non-northern European descent. To our knowledge, this has not been reported in other studies. Our study suggests that careful assessment of the target population prior to the implementation of forensic DNA phenotyping to case work is beneficial.
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Diepenbroek M, Bayer B, Anslinger K. Pushing the Boundaries: Forensic DNA Phenotyping Challenged by Single-Cell Sequencing. Genes (Basel) 2021; 12:genes12091362. [PMID: 34573344 PMCID: PMC8466929 DOI: 10.3390/genes12091362] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/24/2021] [Accepted: 08/27/2021] [Indexed: 12/26/2022] Open
Abstract
Single-cell sequencing is a fast developing and very promising field; however, it is not commonly used in forensics. The main motivation behind introducing this technology into forensics is to improve mixture deconvolution, especially when a trace consists of the same cell type. Successful studies demonstrate the ability to analyze a mixture by separating single cells and obtaining CE-based STR profiles. This indicates a potential use of the method in other forensic investigations, like forensic DNA phenotyping, in which using mixed traces is not fully recommended. For this study, we collected single-source autopsy blood from which the white cells were first stained and later separated with the DEPArray™ N×T System. Groups of 20, 10, and 5 cells, as well as 20 single cells, were collected and submitted for DNA extraction. Libraries were prepared using the Ion AmpliSeq™ PhenoTrivium Panel, which includes both phenotype (HIrisPlex-S: eye, hair, and skin color) and ancestry-associated SNP-markers. Prior to sequencing, half of the single-cell-based libraries were additionally amplified and purified in order to improve the library concentrations. Ancestry and phenotype analysis resulted in nearly full consensus profiles resulting in correct predictions not only for the cells groups but also for the ten re-amplified single-cell libraries. Our results suggest that sequencing of single cells can be a promising tool used to deconvolute mixed traces submitted for forensic DNA phenotyping.
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Wang Y. Association of pigmentation related-genes polymorphisms and geographic environmental variables in the Chinese population. Hereditas 2021; 158:24. [PMID: 34238381 PMCID: PMC8268332 DOI: 10.1186/s41065-021-00189-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 06/09/2021] [Indexed: 11/10/2022] Open
Abstract
Background Human skin color is highly heritable and one of the most variable phenotypic traits. However, the genetic causes and environmental selective pressures underlying this phenotypic variation have remained largely unknown. To investigate whether the pigmentation related-genes polymorphisms are associated with the geographic environmental variables. We selected randomly 795 healthy individuals from eight ethnic groups in nine provinces in China. Six single nucleotide polymorphisms (SNPs) of SLC45A2 and TYR were genotyped using Agena MassARRAY. The Chi-square test and Spearman correlation analysis were used to compare the frequency distribution of genotypes among different ethnic groups and evaluate the relationship between SNP genetic diversity and environmental variables, respectively. Results The results indicated that rs28777 and rs183671 (SLC45A2) and rs1042602 (TYR) genotype frequency distributions were significantly different between the Xinjiang-Uighur and other ethnic groups (P < 0.05). Spearman correlation analysis found that rs28777-A (r = − 0.090, P = 0.011), rs183671-G (r = − 0.105, P = 0.003), rs1042602-A (r = − 0.108, P = 0.002), rs1126809-A (r = − 0.151, P < 0.001) allele frequencies were negatively correlated with the longitude; rs183671-G (r = 0.151), rs1042602-A (r = 0.157) and rs1126809-A (r = 0.138) allele frequencies were positively associated with the latitude (P < 0.001); rs183671-G (r = 0.116, P = 0.001), rs1042602-A (r = 0.105, P = 0.003) and rs1126809-A (r = 0.070, P = 0.048) allele frequencies were positively correlated with the sunshine hours; rs183671-G (r = − 0.076, P = 0.033), rs1042602-A (r = − 0.079, P = 0.027) and rs1126809-A (r = − 0.076, P = 0.031) were negatively correlated with the annual average temperature. Conclusions Our results confirmed the idea that environmental factors have been an important selective pressure upon pigmentation related gene polymorphisms. Supplementary Information The online version contains supplementary material available at 10.1186/s41065-021-00189-7.
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Affiliation(s)
- Yuxin Wang
- Queen Mary School, Nanchang University, 461 Bayi Road, Nanchang, 330006, Jiangxi, China.
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Meyer OS, Salvo NM, Kjærbye A, Kjersem M, Andersen MM, Sørensen E, Ullum H, Janssen K, Morling N, Børsting C, Olsen GH, Andersen JD. Prediction of Eye Colour in Scandinavians Using the EyeColour 11 (EC11) SNP Set. Genes (Basel) 2021; 12:821. [PMID: 34071952 PMCID: PMC8227851 DOI: 10.3390/genes12060821] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 05/20/2021] [Accepted: 05/25/2021] [Indexed: 01/04/2023] Open
Abstract
Description of a perpetrator's eye colour can be an important investigative lead in a forensic case with no apparent suspects. Herein, we present 11 SNPs (Eye Colour 11-EC11) that are important for eye colour prediction and eye colour prediction models for a two-category reporting system (blue and brown) and a three-category system (blue, intermediate, and brown). The EC11 SNPs were carefully selected from 44 pigmentary variants in seven genes previously found to be associated with eye colours in 757 Europeans (Danes, Swedes, and Italians). Mathematical models using three different reporting systems: a quantitative system (PIE-score), a two-category system (blue and brown), and a three-category system (blue, intermediate, brown) were used to rank the variants. SNPs with a sufficient mean variable importance (above 0.3%) were selected for EC11. Eye colour prediction models using the EC11 SNPs were developed using leave-one-out cross-validation (LOOCV) in an independent data set of 523 Norwegian individuals. Performance of the EC11 models for the two- and three-category system was compared with models based on the IrisPlex SNPs and the most important eye colour locus, rs12913832. We also compared model performances with the IrisPlex online tool (IrisPlex Web). The EC11 eye colour prediction models performed slightly better than the IrisPlex and rs12913832 models in all reporting systems and better than the IrisPlex Web in the three-category system. Three important points to consider prior to the implementation of eye colour prediction in a forensic genetic setting are discussed: (1) the reference population, (2) the SNP set, and (3) the reporting strategy.
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Affiliation(s)
- Olivia Strunge Meyer
- Section of Forensic Genetics, Department of Forensic Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark; (A.K.); (N.M.); (C.B.); (J.D.A.)
| | - Nina Mjølsnes Salvo
- Centre for Forensic Genetics, Department of Medical Biology, UiT–The Arctic University of Norway, 9037 Tromsø, Norway; (N.M.S.); (M.K.); (K.J.); (G.-H.O.)
| | - Anne Kjærbye
- Section of Forensic Genetics, Department of Forensic Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark; (A.K.); (N.M.); (C.B.); (J.D.A.)
| | - Marianne Kjersem
- Centre for Forensic Genetics, Department of Medical Biology, UiT–The Arctic University of Norway, 9037 Tromsø, Norway; (N.M.S.); (M.K.); (K.J.); (G.-H.O.)
| | | | - Erik Sørensen
- Department of Clinical Immunology, Copenhagen University Hospital, Rigshospitalet, 2100 Copenhagen, Denmark;
| | - Henrik Ullum
- Statens Serum Institut, 2300 Copenhagen, Denmark;
| | - Kirstin Janssen
- Centre for Forensic Genetics, Department of Medical Biology, UiT–The Arctic University of Norway, 9037 Tromsø, Norway; (N.M.S.); (M.K.); (K.J.); (G.-H.O.)
| | - Niels Morling
- Section of Forensic Genetics, Department of Forensic Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark; (A.K.); (N.M.); (C.B.); (J.D.A.)
| | - Claus Børsting
- Section of Forensic Genetics, Department of Forensic Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark; (A.K.); (N.M.); (C.B.); (J.D.A.)
| | - Gunn-Hege Olsen
- Centre for Forensic Genetics, Department of Medical Biology, UiT–The Arctic University of Norway, 9037 Tromsø, Norway; (N.M.S.); (M.K.); (K.J.); (G.-H.O.)
| | - Jeppe Dyrberg Andersen
- Section of Forensic Genetics, Department of Forensic Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark; (A.K.); (N.M.); (C.B.); (J.D.A.)
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