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1.
Int J Legal Med ; 138(3): 859-872, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38087053

RESUMO

BACKGROUND: Forensic DNA phenotyping (FDP) consists of the use of methodologies for predicting externally visible characteristics (EVCs) from the genetic material of biological samples found in crime scenes and has proven to be a promising tool in aiding human identification in police activities. Currently, methods based on multiplex assays and statistical models of prediction of EVCs related to hair, skin, and iris pigmentation using panels of SNP and INDEL biomarkers have already been developed and validated by the forensic scientific community. As well as traces of pigmentation, an individual's perceived age (PA) can also be considered an EVC and its estimation in unknown individuals can be useful for the progress of investigations. Liu and colleagues (2016) were pioneers in evidencing that, in addition to lifestyle and environmental factors, the presence of SNP and INDEL variants in the MC1R gene - which encodes a transmembrane receptor responsible for regulating melanin production - seems to contribute to an individual's PA. The group highlighted the association between these MC1R gene polymorphisms and the PA in the European population, where carriers of risk haplotypes appeared to be up to 2 years older in comparison to their chronological age (CA). PURPOSE: Understanding that genotype-phenotype relationships cannot be extrapolated between different population groups, this study aimed to test this hypothesis and verify the applicability of this variant panel in the Rio Grande do Sul admixed population. METHODS: Based on genomic data from a sample of 261 volunteers representative of gaucho population and using a multiple linear regression (MLR) model, our group was able to verify a significant association among nine intronic variants in loci adjacent to MC1R (e.g., AFG3L1P, TUBB3, FANCA) and facial age appearance, whose PA was defined after age heteroclassification of standard frontal face images through 11 assessors. RESULTS: Different from that observed in European populations, our results show that the presence of effect alleles (R) of the selected variants in our sample influenced both younger and older face phenotypes. The influence of each variant on PA is expressed as ß values. CONCLUSIONS: There are important molecular mechanisms behind the effects of MC1R locus on PA, and the genomic background of each population seems to be crucial to determine this influence.


Assuntos
DNA , Polimorfismo Genético , Humanos , Fenótipo , DNA/genética , Haplótipos , Cor de Olho/genética , Polimorfismo de Nucleotídeo Único , Genótipo
2.
Mol Biol (Mosk) ; 57(4): 597-608, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37528780

RESUMO

Ancient DNA analyses help to solve the problems related to the genogeographic origin and migration patterns of populations. The Khazar Khaganate is a subject of controversy among researchers. Its complex historical development, lack of a sufficient number of artistic and written sources, the disappearance of representatives of Khazar culture leaves open the question of the appearance of the Khazars. DNA phenotyping of bone remains from elite burials of the Khazar period of Southern Russia was carried out with respect to eye color, hair color, skin color, and AB0 blood groups. Eight out of 10 individuals had brown eyes, dark hair (to varying degrees), and a predominantly dark skin during their lifetime. Individuals from two burials had gray-blue eyes, and one individual had blond hair. The most probable AB0 blood group was identified in eight people, of which five blood group 0 (I) group, four had blood group A (II), and one had blood group B (III). The allele frequency distribution was assessed for ten population-specific autosomal markers and suggested high heterogeneity for the ethnogeographic origin of the Khazars examined. The results are evidence for ethnocultural, genetic, and phenotypic diversity of the Khazar Khaganate.


Assuntos
Antígenos de Grupos Sanguíneos , Cor de Olho , Humanos , DNA/genética , Sepultamento , Federação Russa
3.
Forensic Sci Med Pathol ; 19(3): 335-356, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36401782

RESUMO

Human ear morphology prediction with SNP-based genotypes is growing in forensic DNA phenotyping and is scarcely explored in Pakistan as a part of EVCs (externally visible characteristics). The ear morphology prediction assays with 21 SNPs were assessed for their potential utility in forensic identification of population. The SNaPshot™ multiplex chemistries, capillary electrophoresis methods and GeneMapper™ software were used for obtaining genotypic data. A total of 33 ear phenotypes were categorized with digital photographs of 300 volunteers. SHEsis software was applied to make LD plot. Ordinal and multinomial logistic regression was implemented for association testing. Multinomial logistic regression was executed to construct the prediction model in 90% training and 10% testing subjects. Several influential SNPs for ear phenotypic variation were found in association testing. The model based on genetic markers predicted ear phenotypes with moderate to good predictive accuracies demonstrated with the area under curve (AUC), sensitivity and specificity of predicted phenotypes. As an additional EVC, the estimated ear phenotypic profiles have the possibility of determining the human ear morphology differences in unknown biological samples found in crimes that do not result in a criminal database hit. Furthermore, this can help in facial reconstruction and act as an investigational lead.


Assuntos
DNA , Cor de Olho , Humanos , Genótipo , Fenótipo , Primers do DNA , Genética Forense/métodos , Polimorfismo de Nucleotídeo Único
4.
Mol Biol (Mosk) ; 56(5): 860-880, 2022.
Artigo em Russo | MEDLINE | ID: mdl-36165022

RESUMO

This paper presents a method for genotyping a panel of 60 single nucleotide polymorphisms (SNPs) using single-stage PCR followed by hybridization on a hydrogel biochip. The pool of analyzed polymorphisms consists of 41 SNPs included in the HIrisPlex-S panel, 4 SNPs of the AB0 gene (261G>Del, 297A>G, 657C>T, 681G>A), markers of the AMELX and AMELY genes, and 14 SNP markers of the Y chromosome haplogroups: B (M60), C (M130), D (CTS3946), E (M5388), G (P257), H (M2920), I (U179), J (M304), L (M185), N (M231), O (M175), Q (M1105), R (P224) and T (M272). These genetic data allow one to predict the phenotype of the desired person according to the characteristics of eye, hair, skin color, AB0 blood group, sex, and genogeographic origin in the male line. The setting protocol is simplified as much as possible to facilitate the introduction of the method into practice. The distribution of allele frequencies of the studied polymorphisms, as well as AB0 blood groups among the Slavs (N = 482), originating mainly from central Russia, was established.


Assuntos
Sistema ABO de Grupos Sanguíneos , Cromossomos Humanos Y , Cor de Olho , Técnicas de Genotipagem , Cor de Cabelo , Análise de Sequência com Séries de Oligonucleotídeos , Pigmentação da Pele , Sistema ABO de Grupos Sanguíneos/genética , Cromossomos Humanos Y/genética , Cor de Olho/genética , Cor de Cabelo/genética , Haplótipos , Humanos , Hidrogéis , Masculino , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Polimorfismo de Nucleotídeo Único , Pigmentação da Pele/genética , População Branca/genética
5.
Br J Sociol ; 73(1): 206-219, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34951479

RESUMO

This article counters the view (albeit contested) of race as a natural empirical object with technology as a secondary, external entity applied to it. Instead, I posit race itself as a technology that is inherently discriminatory in motivation, design and function, as evident throughout its brutally effective history. Focusing on the post/genomic era, I consider contemporary forms of molecular racialization as the latest technological iteration of race as a disciplinary device. I characterize this biopolitical racial technology as operant through a carceral methodology in four stages: (a) the epistemological mutability of molecular racialization as reiterating the obscurantist claim of modern raciology to constitute a benign description of literal racial difference; (b) the ontological de-individualization of certain racial others as aggregated risky populations and legitimate targets of repressive management; (c) a predictive empiricism whereby molecular race is seen as indicative of potential behaviours that sanctions oppressive state interventions against specific populations; (d) a normative bioethical dissembling whereby state agencies' exploitation of target molecular racialized populations' vulnerabilities result in the debarment of proper ethical consideration and the right to justice. Drawing largely on criminal justice and immigration control examples, the article asserts that the carceral methodologies of molecular racialization demonstrate race as a repressive technology designed to (re)produce subaltern racial populations and propagate racism.


Assuntos
Racismo , Emigração e Imigração , Humanos , Conhecimento , Grupos Raciais , Tecnologia
6.
Int J Legal Med ; 135(4): 1329-1339, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33884487

RESUMO

Human pigmentation is a complex trait, probably involving more than 100 genes. Predicting phenotypes using SNPs present in those genes is important for forensic purpose. For this, the HIrisPlex tool was developed for eye and hair color prediction, with both models achieving high accuracy among Europeans. Its evaluation in admixed populations is important, since they present a higher frequency of intermediate phenotypes, and HIrisPlex has demonstrated limitations in such predictions; therefore, the performance of this tool may be impaired in such populations. Here, we evaluate the set of 24 markers from the HIrisPlex system in 328 individuals from Ribeirão Preto (SP) region, predicting eye and hair color and comparing the predictions with their real phenotypes. We used the HaloPlex Target Enrichment System and MiSeq Personal Sequencer platform for massively parallel sequencing. The prediction of eye and hair color was accomplished by the HIrisPlex online tool, using the default prediction settings. Ancestry was estimated using the SNPforID 34-plex to observe if and how an individual's ancestry background would affect predictions in this admixed sample. Our sample presented major European ancestry (70.5%), followed by African (21.1%) and Native American/East Asian (8.4%). HIrisPlex presented an overall sensitivity of 0.691 for hair color prediction, with sensitivities ranging from 0.547 to 0.782. The lowest sensitivity was observed for individuals with black hair, who present a reduced European contribution (48.4%). For eye color prediction, the overall sensitivity was 0.741, with sensitivities higher than 0.85 for blue and brown eyes, although it failed in predicting intermediate eye color. Such struggle in predicting this phenotype category is in accordance with what has been seen in previous studies involving HIrisPlex. Individuals with brown eye color are more admixed, with European ancestry decreasing to 62.6%; notwithstanding that, sensitivity for brown eyes was almost 100%. Overall sensitivity increases to 0.791 when a 0.7 threshold is set, though 12.5% of the individuals become undefined. When combining eye and hair prediction, hit rates between 51.3 and 68.9% were achieved. Despite the difficulties with intermediate phenotypes, we have shown that HIrisPlex results can be very helpful when interpreted with caution.


Assuntos
Cor de Olho/genética , Genótipo , Técnicas de Genotipagem/instrumentação , Técnicas de Genotipagem/métodos , Cor de Cabelo/genética , Fenótipo , Brasil/etnologia , Genética Forense/métodos , Humanos
7.
Int J Legal Med ; 135(6): 2175-2187, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34259936

RESUMO

Increasing understanding of human genome variability allows for better use of the predictive potential of DNA. An obvious direct application is the prediction of the physical phenotypes. Significant success has been achieved, especially in predicting pigmentation characteristics, but the inference of some phenotypes is still challenging. In search of further improvements in predicting human eye colour, we conducted whole-exome (enriched in regulome) sequencing of 150 Polish samples to discover new markers. For this, we adopted quantitative characterization of eye colour phenotypes using high-resolution photographic images of the iris in combination with DIAT software analysis. An independent set of 849 samples was used for subsequent predictive modelling. Newly identified candidates and 114 additional literature-based selected SNPs, previously associated with pigmentation, and advanced machine learning algorithms were used. Whole-exome sequencing analysis found 27 previously unreported candidate SNP markers for eye colour. The highest overall prediction accuracies were achieved with LASSO-regularized and BIC-based selected regression models. A new candidate variant, rs2253104, located in the ARFIP2 gene and identified with the HyperLasso method, revealed predictive potential and was included in the best-performing regression models. Advanced machine learning approaches showed a significant increase in sensitivity of intermediate eye colour prediction (up to 39%) compared to 0% obtained for the original IrisPlex model. We identified a new potential predictor of eye colour and evaluated several widely used advanced machine learning algorithms in predictive analysis of this trait. Our results provide useful hints for developing future predictive models for eye colour in forensic and anthropological studies.


Assuntos
DNA , Cor de Olho , DNA/genética , Cor de Olho/genética , Humanos , Fenótipo , Polimorfismo de Nucleotídeo Único , Software
8.
Int J Legal Med ; 135(4): 1425-1432, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33847802

RESUMO

A European-wide online survey was conducted to generate an overview on the state-of-the-art using massively parallel sequencing (MPS) platforms for forensic DNA analysis and DNA phenotyping among forensic practitioners in Europe. The survey was part of the dissemination activities of the "VISible Attributes through GEnomics - VISAGE" Horizon 2020 funded European research project [30], in preparation of a series of educational training activities. A total of 105 replies from 32 European countries representing participants from police, governmental, academic, and private laboratories providing professional services in the field of forensic genetics were included in the final analysis. Of these, 73% already own an MPS platform or are planning to acquire one within the next 1-2 years. One-third of the participants have already carried out MPS-based STR sequencing, identity, or ancestry SNP typing. A total of 23-40% of participants are planning to explore all FDP applications showing the overall very high interest in using MPS for the whole range of forensic MPS markers and applications. About 50% of the participants have previously gathered experience using forensic DNA phenotyping (FDP) markers based on conventional (i.e., not MPS-based) DNA typing methods. A total of 55% of the participants have attended training on the general use of MPS technology, but 36% have received no training whatsoever. Accordingly, 90% have expressed high or medium interest to attend training on the analysis and interpretation of DNA phenotyping data for predicting appearance, ancestry, and age. The results of our survey will provide valuable information for organizing relevant training workshops on all aspects of MPS-based DNA phenotyping for the forensic genetics scientific community.


Assuntos
Impressões Digitais de DNA/métodos , Genética Forense/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Europa (Continente) , Genética Forense/educação , Humanos , Laboratórios/organização & administração , Inquéritos e Questionários
9.
Int J Legal Med ; 135(5): 1743-1752, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33969445

RESUMO

The eyelid folding represents one of the most distinguishing features of East Asian faces, involving the absence or presence of the eyelid crease, i.e., single vs. double eyelid. Recently, a genome-wide association study (GWAS) identified two SNPs (rs12570134 and rs1415425) showing genome-wide significant association with the double eyelid phenotype in Japanese. Here we report a confirmatory study in 697 Chinese individuals of exclusively Han origin. Only rs1415425 was statistically significant (P-value = 0.011), and the allele effect was on the same direction with that reported in Japanese. This SNP combined with gender and age explained 10.0% of the total variation in eyelid folding. DNA-based prediction model for the eyelid trait was developed and evaluated using logistic regression. The model showed mild to moderate predictive capacity (AUC = 0.69, sensitivity = 63%, and specificity = 70%). We further selected six additional SNPs by massive parallel sequencing of 19 candidate genes in 24 samples, and one SNP rs2761882 was statistically significant (P-value = 0.027). All predictors including these two SNPs (rs1415425 and rs2761882), gender, and age explained 11.2% of the total variation. The combined prediction model obtained an improved predictive capacity (AUC = 0.72, sensitivity = 62%, and specificity = 66%). Our study thus provided a confirmation of previous GWAS findings and a DNA-based prediction of the eyelid trait in Chinese Han individuals. This model may add value to forensic DNA phenotyping applications considering gender and age can be separately inferred from genetic and epigenetic markers. To further improve the prediction accuracy, future studies should focus on identifying more informative SNPs by large GWASs in East Asian populations.


Assuntos
Pálpebras/anatomia & histologia , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Fenótipo , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Adulto , Área Sob a Curva , Povo Asiático/genética , China/etnologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade
10.
Int J Legal Med ; 134(5): 1569-1579, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32385594

RESUMO

Although many genes have been shown to be associated with human pigmentary traits and forensic prediction assays exist (e.g. HIrisPlex-S), the genetic knowledge about skin colour remains incomplete. The highly admixed Brazilian population is an interesting study population for investigation of the complex genotype-phenotype architecture of human skin colour because of its large variation. Here, we compared variants in 22 pigmentary genes with quantitative skin pigmentation levels on the buttock, arm, and forehead areas of 266 genetically admixed Brazilian individuals. The genetic ancestry of each individual was estimated by typing 46 AIM-InDels. The mean proportion of genetic ancestry was 68.8% European, 20.8% Sub-Saharan African, and 10.4% Native American. A high correlation (adjusted R2 = 0.65, p < 0.05) was observed between nine SNPs and quantitative skin pigmentation using multiple linear regression analysis. The correlations were notably smaller between skin pigmentation and biogeographic ancestry (adjusted R2 = 0.45, p < 0.05), or markers in the leading forensic skin colour prediction system, the HIrisPlex-S (adjusted R2 = 0.54, p < 0.05). Four of the nine SNPs, OCA2 rs1448484 (rank 2), APBA2 rs4424881 (rank 4), MFSD12 rs10424065 (rank 8), and TYRP1 1408799 (rank 9) were not investigated as part of the HIrisPlex-S selection process, and therefore not included in the HIrisPlex-S model. Our results indicate that these SNPs account for a substantial part of the skin colour variation in individuals of admixed ancestry. Hence, we suggest that these SNPs are considered when developing future skin colour prediction models.


Assuntos
Variação Genética , Polimorfismo de Nucleotídeo Único , Pigmentação da Pele/genética , População Negra/genética , Brasil/etnologia , DNA/genética , Marcadores Genéticos , Técnicas de Genotipagem/instrumentação , Humanos , Povos Indígenas/genética , População Branca/genética
11.
Proc Natl Acad Sci U S A ; 114(38): 10166-10171, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28874526

RESUMO

Prediction of human physical traits and demographic information from genomic data challenges privacy and data deidentification in personalized medicine. To explore the current capabilities of phenotype-based genomic identification, we applied whole-genome sequencing, detailed phenotyping, and statistical modeling to predict biometric traits in a cohort of 1,061 participants of diverse ancestry. Individually, for a large fraction of the traits, their predictive accuracy beyond ancestry and demographic information is limited. However, we have developed a maximum entropy algorithm that integrates multiple predictions to determine which genomic samples and phenotype measurements originate from the same person. Using this algorithm, we have reidentified an average of >8 of 10 held-out individuals in an ethnically mixed cohort and an average of 5 of either 10 African Americans or 10 Europeans. This work challenges current conceptions of personal privacy and may have far-reaching ethical and legal implications.


Assuntos
Confidencialidade , Impressões Digitais de DNA , Modelos Genéticos , Fenótipo , Sequenciamento Completo do Genoma , Adulto , Fatores Etários , Algoritmos , Tamanho Corporal , Estudos de Coortes , Anonimização de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pigmentação/genética , Adulto Jovem
12.
Int J Legal Med ; 133(6): 1667-1679, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30976986

RESUMO

Accurate genomic profiling for adult height is of high practical relevance in forensics genetics. Adult height is a classical reference trait in the field of human complex trait genetics characterized by highly polygenic nature and relatively high heritability. A meta-analysis of genome-wide association studies by the Genetic Investigation of Anthropocentric Traits (GIANT) consortium has identified 697 DNA variants associated with adult height in Europeans; however, whether these variants will still be informative in non-Europeans is still in question. The present study investigated the predictive power of these 697 height-associated SNPs in 687 Uyghurs of European-Asian admixed origin. Among all GIANT SNPs, 11% showed nominally significant association (6.78 × 10-4 < p < 0.05) with adult height in the Uyghur population and among the significant SNPs 77% of allele effects were in the same direction as those in Europeans reported in the GIANT study. Fitting linear and logistic models using a polygenic score consisting of all GIANT SNPs resulted in an 80-20 cross-validated mean R2 of 10.08% (95% CI 3.16-18.40%) for quantitative height prediction and a mean AUC value of 0.65 (95% CI 0.57-0.72%) for qualitative "above average" prediction. Fine-tuning the SNP set using their association p values considerably improved the prediction results (number of SNPs = 62, R2 = 15.59%, 95% CI 6.80-25.71%; AUC = 0.70, 95% CI 62-0.77) in the Uyghurs. Overall, our findings demonstrate substantial differences between the European and Asian populations in the genetics of adult height, emphasizing the importance of population heterogeneity underlying the genetic architecture of adult height.


Assuntos
Estatura/genética , Etnicidade/genética , Genética Populacional , Polimorfismo de Nucleotídeo Único , Adulto , Povo Asiático/genética , Queixo , Frequência do Gene , Genótipo , Humanos , Modelos Lineares , Masculino , População Branca/genética
13.
Gerontology ; 64(4): 326-332, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29393215

RESUMO

Forensic genetics developed from protein-based techniques a quarter of a century ago and became famous as "DNA fingerprinting," this being based on restriction fragment length polymorphisms (RFLPs) of high-molecular-weight DNA. The amplification of much smaller short tandem repeat (STR) sequences using the polymerase chain reaction soon replaced RFLP analysis and advanced to become the gold standard in genetic identification. Meanwhile, STR multiplexes have been developed and made commercially available which simultaneously amplify up to 30 STR loci from as little as 15 cells or fewer. The enormous information content that comes with the large variety of observed STR genotypes allows for genetic individualisation (with the exception of identical twins). Carefully selected core STR loci form the basis of intelligence-led DNA databases that provide investigative leads by linking unsolved crime scenes and criminals through their matched STR profiles. Nevertheless, the success of modern DNA fingerprinting depends on the availability of reference material from suspects. In order to provide new investigative leads in cases where such reference samples are absent, forensic scientists started to explore the prediction of phenotypic traits from the DNA of the evidentiary sample. This paradigm change now uses DNA and epigenetic markers to forecast characteristics that are useful to triage further investigative work. So far, the best investigated externally visible characteristics are eye, hair and skin colour, as well as geographic ancestry and age. Information on the chronological age of a stain donor (or any sample donor) is elemental for forensic investigations in a number of aspects and has, therefore, been explored by researchers in some detail. Among different methodological approaches tested to date, the methylation-sensitive analysis of carefully selected DNA markers (CpG sites) has brought the most promising results by providing prediction accuracies of ±3-4 years, which can be comparable to, or even surpass those from, eyewitness reports. This mini-review puts recent developments in age estimation via (epi)genetic methods in the context of the requirements and goals of forensic genetics and highlights paths to follow in the future of forensic genomics.


Assuntos
Envelhecimento/genética , Impressões Digitais de DNA/métodos , Epigenômica/métodos , Genética Forense/métodos , Ilhas de CpG , Impressões Digitais de DNA/tendências , Bases de Dados de Ácidos Nucleicos , Epigenômica/tendências , Genética Forense/tendências , Humanos , Repetições de Microssatélites
14.
Int J Legal Med ; 131(1): 21-37, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27841004

RESUMO

Short tandem repeats are the gold standard for human identification but are not informative for forensic DNA phenotyping (FDP). Single-nucleotide polymorphisms (SNPs) as genetic markers can be applied to both identification and FDP. The concept of DNA intelligence emerged with the potential for SNPs to infer biogeographical ancestry (BGA) and externally visible characteristics (EVCs), which together enable the FDP process. For more than a decade, the SNaPshot® technique has been utilised to analyse identity and FDP-associated SNPs in forensic DNA analysis. SNaPshot is a single-base extension (SBE) assay with capillary electrophoresis as its detection system. This multiplexing technique offers the advantage of easy integration into operational forensic laboratories without the requirement for any additional equipment. Further, the SNP panels from SNaPshot® assays can be incorporated into customised panels for massively parallel sequencing (MPS). Many SNaPshot® assays are available for identity, BGA and EVC profiling with examples including the well-known SNPforID 52-plex identity assay, the SNPforID 34-plex BGA assay and the HIrisPlex EVC assay. This review lists the major forensically relevant SNaPshot® assays for human DNA SNP analysis and can be used as a guide for selecting the appropriate assay for specific identity and FDP applications.


Assuntos
DNA/genética , Eletroforese Capilar , Genética Forense/métodos , Polimorfismo de Nucleotídeo Único , Animais , Bactérias/genética , Tipagem e Reações Cruzadas Sanguíneas/métodos , Cromossomos Humanos Y , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Cor de Olho/genética , Genética Populacional , Genótipo , Técnicas de Genotipagem , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Insetos/genética , Reação em Cadeia da Polimerase Multiplex , Grupos Raciais/genética , Pigmentação da Pele/genética
15.
Int J Legal Med ; 130(4): 923-934, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27221533

RESUMO

The genetics of eye colour has been extensively studied over the past few years, and the identified polymorphisms have been applied with marked success in the field of Forensic DNA Phenotyping. A picture that arises from evaluation of the currently available eye colour prediction markers shows that only the analysis of HERC2-OCA2 complex has similar effectiveness in different populations, while the predictive potential of other loci may vary significantly. Moreover, the role of gender in the explanation of human eye colour variation should not be neglected in some populations. In the present study, we re-investigated the data for 1020 Polish individuals and using neural networks and logistic regression methods explored predictive capacity of IrisPlex SNPs and gender in this population sample. In general, neural networks provided higher prediction accuracy comparing to logistic regression (AUC increase by 0.02-0.06). Four out of six IrisPlex SNPs were associated with eye colour in the studied population. HERC2 rs12913832, OCA2 rs1800407 and SLC24A4 rs12896399 were found to be the most important eye colour predictors (p < 0.007) while the effect of rs16891982 in SLC45A2 was less significant. Gender was found to be significantly associated with eye colour with males having ~1.5 higher odds for blue eye colour comparing to females (p = 0.002) and was ranked as the third most important factor in blue/non-blue eye colour determination. However, the implementation of gender into the developed prediction models had marginal and ambiguous impact on the overall accuracy of prediction confirming that the effect of gender on eye colour in this population is small. Our study indicated the advantage of neural networks in prediction modeling in forensics and provided additional evidence for population specific differences in the predictive importance of the IrisPlex SNPs and gender.


Assuntos
Cor de Olho/genética , Polimorfismo de Nucleotídeo Único , Antiporters/genética , Feminino , Genética Populacional , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Modelos Logísticos , Masculino , Proteínas de Membrana Transportadoras/genética , Redes Neurais de Computação , Polônia , Fatores Sexuais , Ubiquitina-Proteína Ligases
16.
Semin Cell Dev Biol ; 24(6-7): 562-75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23587773

RESUMO

In this review article we summarize current knowledge on how variation on the DNA level influences human pigmentation including color variation of iris, hair, and skin. We review recent progress in the field of human pigmentation genetics by focusing on the genes and DNA polymorphisms discovered to be involved in determining human pigmentation traits, their association with diseases particularly skin cancers, and their power to predict human eye, hair, and skin colors with potential utilization in forensic investigations.


Assuntos
DNA/genética , Pigmentação/genética , Polimorfismo Genético/genética , Cor , Humanos
17.
Int J Legal Med ; 129(6): 1191-200, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26289415

RESUMO

DNA phenotyping research is one of the most emergent areas of forensic genetics. Predictions of externally visible characteristics are possible through analysis of single nucleotide polymorphisms. These tools can provide police with "intelligence" in cases where there are no obvious suspects and unknown biological samples found at the crime scene do not result in any criminal DNA database hits. IrisPlex, an eye color prediction assay, revealed high prediction rates for blue and brown eye color in European populations. However, this is less predictive in some non-European populations, probably due to admixing. When compared to other European countries, Portugal has a relatively admixed population, resulting from a genetic influx derived from its proximity to and historical relations with numerous African territories. The aim of this work was to evaluate the utility of IrisPlex in the Portuguese population. Furthermore, the possibility of supplementing this multiplex with additional markers to also achieve skin color prediction within this population was evaluated. For that, IrisPlex was augmented with additional SNP loci. Eye and skin color prediction was estimated using the multinomial logistic regression and binomial logistic regression models, respectively. The results demonstrated eye color prediction accuracies of the IrisPlex system of 90 and 60% for brown and blue eye color, respectively, and 77% for intermediate eye color, after allele frequency adjustment. With regard to skin color, it was possible to achieve a prediction accuracy of 93%. In the future, phenotypic determination multiplexes must include additional loci to permit skin color prediction as presented in this study as this can be an advantageous tool for forensic investigation.


Assuntos
Cor de Olho/genética , Polimorfismo de Nucleotídeo Único , Pigmentação da Pele/genética , Adolescente , Adulto , Idoso , Antígenos de Neoplasias/genética , Antiporters/genética , Feminino , Genética Forense , Genética Populacional , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Fatores Reguladores de Interferon/genética , Modelos Logísticos , Masculino , Proteínas de Membrana Transportadoras/genética , Pessoa de Meia-Idade , Fenótipo , Portugal , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Ubiquitina-Proteína Ligases , Adulto Jovem
18.
Forensic Sci Int Genet ; 68: 102976, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38000161

RESUMO

RNA has gained a substantial amount of attention within the forensic field over the last decade. There is evidence that RNAs are differentially expressed with biological age. Since RNA can be co-extracted with DNA from the same piece of evidence, RNA-based analysis appears as a promising molecular alternative for predicting the biological age and hence inferring the chronological age of a person. Using RNA-Seq data we searched for markers in blood potentially associated with age. We used our own RNA-Seq data from dried blood stains as well as publicly available RNA-Seq data from whole blood, and compared two different approaches to select candidate markers. The first approach focused on individual gene analysis with DESeq2 to select the genes most correlated with age, while the second approach employed lasso regression to select a set of genes for optimal prediction of age. We present two lists with 270 candidate markers, one for each approach.


Assuntos
Corantes , DNA , Humanos , RNA Mensageiro/genética , DNA/análise , Genética Forense
19.
Forensic Sci Int Genet ; 74: 103154, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39426120

RESUMO

INTRODUCTION: The field of forensic DNA analysis has undergone rapid advancements in recent decades. The integration of massively parallel sequencing (MPS) has notably expanded the forensic toolkit, moving beyond identity matching to predicting phenotypic traits and biogeographical ancestry. This shift is of particular significance in cases where conventional DNA profiling fails to identify a single suspect. Supplementing forensic analyses with estimated biological age may be valuable but involves a complex and time-consuming DNA methylation analysis. This study explores and validates the performance of a comprehensive forensic third-generation sequencing assay utilizing Oxford Nanopore Technologies (ONT) in an adaptive and direct sequencing approach. We incorporated the most widely used forensic markers, i.e., STRs, SNPs, InDels, mitochondrial DNA (mtDNA), and two methylation-based clock classifiers, thereby combining forensic genetic and epigenetic analysis in one single workflow. METHODS AND RESULTS: In our investigation, DNA from six anonymous individuals was sequenced using the ONT standard adaptive direct sequencing approach, reaching a mean percentage of on-target reads ranging from 6.6 % to 7.7 % per sample. ONT data was compared to standard MPS data and Illumina EPIC DNA methylation profiles. Basecalling employed recommended ONT software packages. TREAT was used for ONT-based analysis of autosomal and Y-chromosome STRs, achieving 90-92 % correct calls depending on allelic read depth thresholds. InDel analyses for two lower-quality samples proved challenging due to inadequate read depth, while the remaining four samples significantly contributed to the observed percentage markers (60.9 %) and correct calls (97.8 %). SNP analysis achieved a 98 % call rate, with only two mismatches and two missed alleles. ONT-generated DNA methylation data demonstrated Pearson's correlation coefficients with EPIC data ranging from 0.67 to 0.97 for Horvath's clock. Additional age-associated markers exhibited Pearson's correlation coefficients with chronological age between 0.14 (ELOVL2) and 0.96 (FHL2) at read depths of <30 and <20, respectively. Despite excluding mtDNA from our targeted sequencing approach, adaptive proof-reading fragments covered the complete mtDNA with an average read depth of 21-72, showing 100 % concordance with reference data. DISCUSSION: Our exploratory study using ONT adaptive sequencing for conventional forensic and age associated DNA methylation markers showed high sequencing accuracy for a significant number of markers, showcasing ONT as a promising (epi)genetic forensic method. Future studies must address three critical aspects: determining clear quantity and quality measures and detection thresholds for accuracy, optimizing input DNA quantity for forensic casework expectations, and addressing ethical considerations associated with phenotype and ancestry analysis to prevent ethnic biases.

20.
BMC Res Notes ; 17(1): 51, 2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38369539

RESUMO

OBJECTIVES: The collection of genotype data was conducted as an essential part of a pivotal research project with the goal of examining the genetic variability of skin, hair, and iris color among the Kazakh population. The data has practical application in the field of forensic DNA phenotyping (FDA). Due to the limited size of forensic databases from Central Asia (Kazakhstan), it is practically impossible to obtain an individual identification result based on forensic profiling of short tandem repeats (STRs). However, the pervasive use of the FDA necessitates validation of the currently employed set of genetic markers in a variety of global populations. No such data existed for the Kazakhs. The Phenotype Expert kit (DNA Research Center, LLC, Russia) was used for the first time in this study to collect data. DATA DESCRIPTION: The present study provides genotype data for a total of 60 SNP genetic markers, which were analyzed in a sample of 515 ethnic Kazakhs. The dataset comprises a total of 41 single nucleotide polymorphisms (SNPs) obtained from the HIrisPlex-S panel. Additionally, there are 4 SNPs specifically related to the AB0 gene, 1 marker associated with the AMELX/Y genes, and 14 SNPs corresponding to the primary haplogroups of the Y chromosome. The aforementioned data could prove valuable to researchers with an interest in investigating genetic variability and making predictions about phenotype based on eye color, hair color, skin color, AB0 blood group, gender, and biogeographic origin within the male lineage.


Assuntos
Sistema ABO de Grupos Sanguíneos , População da Ásia Central , Cromossomos Humanos Y , Haplótipos , Pigmentação , Humanos , Masculino , Sistema ABO de Grupos Sanguíneos/genética , População da Ásia Central/genética , Cromossomos Humanos Y/genética , DNA/genética , Marcadores Genéticos , Genética Populacional , Genótipo , Cabelo , Haplótipos/genética , Polimorfismo de Nucleotídeo Único/genética , Pigmentação da Pele/genética , Pigmentação/genética , Variação Genética/genética
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