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1.
Ann Hum Biol ; 50(1): 351-355, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37668227

RESUMO

BACKGROUND: X-chromosomal short tandem repeats (X-STRs) are a useful supplementary approach to analysing autosomal markers in forensics and kinship studies; such markers are not well-characterised in many populations. AIM: To investigate population genetic polymorphism and forensic characterisation of 16 X-STRs in the Jining Han population, and analyse genetic relationships with other Chinese populations. SUBJECTS AND METHODS: Allele frequencies for 16 X-STR loci were obtained from a sample set of 527 unrelated individuals from the Jining Han population. Population genetic analyses of Jining Han and another 10 reference populations were conducted using phylogenetic tree, principal component analysis and multidimensional scaling. RESULTS: We detected 149 alleles, with frequencies ranging from 0.0013 to 0.8242. The combined powers of discrimination in males and females were 0.999999997194774 and 0.999999999999995, respectively. The combined mean exclusion change (MEC)Krüger, MECKishida, MECDesmarais, and MECDesmarais Duos values were 0.999974632649096, 0.999999976997582, 0.999999977013201, and 0.999993755768423, respectively. We detected relatively high genetic homogeneity in populations with similar ethnic or geographic origins, and a close relationship between the Jining Han and Beijing Han populations. CONCLUSIONS: The present findings indicate that the 16 X-STR loci examined are highly polymorphic in the Han population of Jining, providing useful information for forensic science and population genetics studies.


Assuntos
Cromossomos Humanos X , População do Leste Asiático , Repetições de Microssatélites , Feminino , Humanos , Masculino , Alelos , China , Filogenia , População do Leste Asiático/genética , Cromossomos Humanos X/genética
2.
Int J Legal Med ; 136(2): 561-563, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34420081

RESUMO

X-chromosomal STRs are a powerful tool to assess a broad variety of complex kinship scenarios. We introduce herewith the first Swiss X-STR dataset based on 1198 individuals (592 female, 606 male), characterized with the Qiagen Investigator® Argus X-12 QS multiplex kit. Anomalous allele patterns, allele and haplotype frequencies, and forensic and population genetic parameters are presented. We detected linkage disequilibrium within three out of the four designated linkage groups and no apparent intra-national population substructure. We compared the dataset to a global panel of X-STR datasets and it fits well in the European context, as expected.


Assuntos
Genética Populacional , Repetições de Microssatélites , Cromossomos Humanos X , Impressões Digitais de DNA , Feminino , Frequência do Gene , Haplótipos , Humanos , Masculino , Suíça
3.
Int J Legal Med ; 136(2): 543-545, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33180199

RESUMO

To investigate the genetic variation and forensic efficiency of 16 X-chromosomal short tandem repeat (X-STR) loci (DX6795, DXS9902, DXS8378, HPRTB, GATA165B12, DXS7132, DXS7424, DXS6807, DXS6803, GATA172D05, DXS6800, DXS10134, GATA31E08, DXS10159, DXS6789, and DXS6810) in the Bai minority, we calculated allele frequencies, forensic parameters, and haplotype frequencies in 424 (202 males and 222 females) unrelated, healthy Bai individuals from Dali Bai Autonomous Prefecture in Yunnan Province, China. We observed a total of 132 alleles; 5-19 alleles were detected in each locus, and the corresponding allele frequencies ranged from 0.0016 to 0.7589. All of the loci detected were highly polymorphic in the Bai population in Yunnan Province, except DXS6800. The values for the combined power of discrimination in females (PDf) and males (PDm) were 0.999999999999996 and 0.999999997487061, respectively. According to a phylogenetic tree, neighboring populations and different nationalities in the same area appeared to have relatively close evolutionary relationships. This study provides and complements X-chromosome genetic polymorphism data for the Bai people in Yunnan Province, Southwest China, and enriches the available reference materials for this Chinese minority population.


Assuntos
Minorias Étnicas e Raciais , Etnicidade , China , Cromossomos Humanos X , Etnicidade/genética , Feminino , Frequência do Gene , Genética Populacional , Humanos , Masculino , Repetições de Microssatélites , Grupos Minoritários , Filogenia , Polimorfismo Genético
4.
Int J Legal Med ; 136(2): 513-518, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34741211

RESUMO

X-chromosomal short tandem repeats (X-STRs) are useful for the identification of absent single parents and complex blood relations. In the present study, we aimed to identify novel STR loci for use as DNA markers by conducting polymorphism and haplotype analyses. We detected three novel STR loci (LC552061, LC552062, and LC552063, with repetitive structures of (GGAA)n(GGGA)m, (CCTT)n(CCCT)m, and (ATTT)n, respectively) in the p11.4 region of the X chromosome. For these X-STRs, the polymorphism information content values ranged from 0.5766 to 0.6377 and the power of discrimination in males and females ranged from 0.6269 to 0.6844 and from 0.8105 to 0.8537, respectively. The linkage disequilibrium analysis revealed p values of < 0.0001, < 0.0001, and 0.00909 between LC552061 and LC552062, LC552061 and LC552063, and LC552062 and LC552063, respectively. Additional linkage disequilibrium analysis including seven previously analyzed loci (LC149476, LC149479, LC149480, LC149484, LC317283, LC317284, and LC317285) revealed a p value of < 0.001 among each of the five loci (LC149476, LC149479, LC149480, LC149484, and LC317283) and between LC317284 and LC317285, indicating that they were a linked group. These results indicate that, in addition to the seven previously detected loci, the three novel X-STR loci identified in the present study might be useful DNA markers for complex kinship analysis and might support the Investigator® Argus X-12 kit.


Assuntos
Cromossomos Humanos X , Genética Populacional , Feminino , Frequência do Gene , Haplótipos , Humanos , Masculino , Repetições de Microssatélites , Polimorfismo Genético
5.
Electrophoresis ; 42(6): 766-773, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33415769

RESUMO

With a unique inheritance pattern compared to autosomal short tandem repeats (A-STRs), X chromosomal STRs (X-STRs) have special usage in forensic relationship testing. In this study, we designed a multiplex amplification system (named TYPER-X19 multiplex assay) consisting of 18 STR loci spreading from 7.837 to 149.460 Mb on the X chromosomes (DXS9895, DXS8378, DXS9902, DXS6810, DXS7132, DXS10079, DXS6789, DXS7424, DXS101, DXS6797, DXS7133, DXS6804, GATA165B12, DXS10103, HPRTB, GATA31E08, DXS8377, and DXS7423), and the amelogenin. PCR primers were marked with four kinds of fluorophores including FAM, HEX, TAMRA, and ROX. The multiplex system was optimized and tested for precision, concordance, reproducibility, sensitivity, stability, DNA mixture, and species specificity according to the conventional validation guidelines. The results indicated that the system was accurate, reliable, and sensitive enough, and was suitable for common forensic case-type samples. In the population genetic study, a total of 148 alleles were detected at the 18 X-STR loci in 398 Southern Han Chinese. Relatively high combined power of discrimination in male (PDm ), power of discrimination in female (PDf ), mean paternity exclusion chance in trios (MECtrio ), and mean paternity exclusion chance in duos (MECDuo ) by Desmarais were detected, and HPRTB-DXS10103 was in linkage disequilibrium. The results suggested that the TYPER-X19 multiplex assay was suitable for forensic applications.


Assuntos
Cromossomos Humanos X , Genética Forense , Genética Populacional , Cromossomos Humanos X/genética , Impressões Digitais de DNA , Feminino , Frequência do Gene , Humanos , Masculino , Repetições de Microssatélites/genética , Reprodutibilidade dos Testes
6.
Int J Legal Med ; 135(3): 787-790, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33392656

RESUMO

In this study, we investigate the forensic and population genetics properties of 21 X-chromosome markers (9 X-Alu insertions and 12 X-STRs) in a dataset composed of 716 individuals from 11 Western Mediterranean populations. The high values of combined forensic parameters indicate that this 21 X-loci panel can complement autosomal or uniparental markers in kinship analysis and complex deficient paternity testing in the populations studied. Population analyses revealed a lower differentiation between Western Mediterranean human groups for X-STRs than for X-Alu insertion polymorphisms. Moreover, X-chromosome markers suggest a sex-biased migration rate, confirming the predominance of patrilocality in this area.


Assuntos
Cromossomos Humanos X , Etnicidade/genética , Marcadores Genéticos , Genética Populacional , Feminino , Genética Forense , Humanos , Masculino , Região do Mediterrâneo/etnologia
7.
Ann Hum Biol ; 48(7-8): 621-626, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34789047

RESUMO

BACKGROUND: X-chromosomes show a specific genetic mode, which makes genetic markers on the X-chromosome play crucial roles in forensic research and human evolution. Dong group, one of 55 minority groups in China, live in Guizhou, Guangxi, and Hunan provinces. Even though some genetic data of Y chromosomal short tandem repeats (STRs) and autosomal insertion/deletion polymorphism (InDels) in Dong groups have been reported, there is little research about X-STRs in the Dong group. AIM: Purposes of this study are to investigate allelic distributions and forensic statistical parameters of 19 X-STRs in the Guizhou Dong group, and explore the genetic composition of the Guizhou Dong group and its phylogenetic relationships with other reference populations. SUBJECTS AND METHODS: Five hundred and seven Dongs (272 males and 235 females) living in Guizhou province were typed using the AGCU X19 STR kit. Allelic frequencies and forensic parameters of 19 X-STRs in the Guizhou Dong group were calculated. Population genetic analyses of Guizhou Dong and another 17 reference populations were conducted using DA genetic distances, phylogenetic tree, principal component analysis, and multidimensional scaling. RESULTS: A total of 230 alleles of 19 X-STRs were identified in all Dongs. The frequencies of 19 loci ranged from 0.0013 to 0.6838. The values for cumulative power of discrimination in males (PDM), cumulative power of discrimination in females (PDF), and four different kinds of mean exclusion chance (MEC_Kruger, MEC_Kishida, MEC_Desmarais, and MEC_Desmarais_du) for the 19 X-STRs in all individuals were 0.999999999999761, 0.9999999999999999999993951, 0.999999964841617, 0.999999999997261, 0.999999999997297, and 0.999999993623172, respectively. Besides, genetic polymorphisms of seven linkage clusters ranged from 0.9381 to 0.9963. In addition, these seven groups showed high polymorphism information content (PIC), PDM, PDF, MEC_Kruger, MEC_Kishida, MEC_Desmarais, and MEC_Desmarais_duo. Population genetic analyses of Guizhou Dong and another 17 reference populations showed that the Guizhou Dong group had close genetic relationships with surrounding Tai-Kadai-speaking, Hmong-Mien-speaking, and Han groups. CONCLUSION: Nineteen X-STRs displayed high genetic diversities and could be employed for forensic personal identification and paternity analysis in the Guizhou Dong group. Close genetic affinities between Guizhou Dong and surrounding populations were observed based on the 19 X-STRs in 17 reference populations.


Assuntos
Etnicidade , Repetições de Microssatélites , China , Feminino , Frequência do Gene , Genética Populacional , Humanos , Masculino , Filogenia
8.
Ann Hum Biol ; 48(5): 430-436, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34514921

RESUMO

BACKGROUND: X-chromosome specific short tandem repeats (X-STR) are indispensable for parentage analysis, kinship determination and forensic casework. AIM: To determine allelic frequencies and forensic parameters of the 12 X-STR markers from the Investigator® Argus X-12® kit panel for the population of the Russian Federation. SUBJECTS AND METHODS: We analysed 803 unrelated individuals from 58 localities across the Russian Federation. Intra-population genetic diversity was evaluated and comparison of the Russian population with 19 geographically distant populations performed. RESULTS: Heterozygosity values across all the loci ranged from 0.685 for DXS7423 to 0.939 for DXS10135. Deviations from the Hardy-Weinberg equilibrium were observed for DXS10074 (p < 0.05) and DXS10146 (p < 0.01). The value for power of discrimination across all the loci in males was 0.9999999996, while in females it equalled 0.9999999999. Combined mean exclusion chances MECKruger, MECKishida, MECD-trio, and MECD-duo were 0.9999988168, 0.9999999983, 0.9999999983, and 0.9999995797, respectively. Phylogenetic analysis indicated small genetic differences between the Russian population and the populations of neighbouring Lithuania, Belarus and the Slavic-speaking countries (Czech Republic, Serbia and Croatia). CONCLUSIONS: This paper is the first report of forensically important parameters and allele frequencies for the 12 X-STR loci included in Argus X-12® marker system in the population of the Russian Federation.


Assuntos
Cromossomos Humanos X , Impressões Digitais de DNA , Genética Populacional , Repetições de Microssatélites , Cromossomos Humanos X/genética , Feminino , Variação Genética , Humanos , Masculino , Filogenia , Federação Russa
9.
Ann Hum Biol ; 47(5): 490-497, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32605398

RESUMO

BACKGROUND: The Jat Sikh population is the largest endogamous group of Punjab, a state in north-west India, and has not yet been explored for genetic polymorphism based on X-STR genetic markers. In India, which is the second most populous country in the world, only two population studies based on X-STR markers have been reported so far. AIM: To explore the genetic diversity of 12 X chromosomal STR genetic markers in the Jat Sikh population of Punjab and expand the X-STR polymorphism database. SUBJECTS AND METHODS: In this study, a total of 200 Jat Sikh individuals (100 males and 100 females) residing in Punjab were investigated for 12 X-STR markers using the Investigator Argus X-12 QS Kit. RESULTS: The highest power of discrimination (PD) in females (PDf) and males (PDm) was observed to be 0.965 (DXS10135) and 0.929 (DXS10135 and DXS10148), respectively. DXS10135 was found to be the most polymorphic and discriminating locus among all the studied loci in both males and females with highest values of power of discrimination (PD) and polymorphic information content (PIC) as well. CONCLUSION: Overall, the studied markers of the Argus 12 X-STR kit provide high polymorphic information which may prove to be an important tool in resolving issues such as missing person identification, incest, immigration disputes, kinship analysis and genealogical studies. The dataset obtained from this study will add to the present database of X-STRs.


Assuntos
Cromossomos Humanos X/genética , Marcadores Genéticos , Variação Genética , Genoma Humano , Repetições de Microssatélites , Feminino , Genótipo , Humanos , Índia , Masculino
10.
Int J Legal Med ; 133(1): 39-44, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29564553

RESUMO

StatsX (Statistics for X-STR) v2.0 is developed to facilitate the workflow for analysis of population data on X-chromosomal short tandem repeat (X-STR) marker. The interactive graphical and installable software can estimate allele/haplotype frequencies from female, male, and pooled samples and calculate forensic parameters by importing a single file. In addition, it is able to filter out the invalid raw data and export a series of pre-formatted Arlequin input files that are directly used for testing the significance of the Hardy-Weinberg equilibrium (HWE), linkage disequilibrium (LD), and gender differentiation. As expected, all results of frequencies and forensic parameters can be saved as EXCEL workbooks and also plotted as bar or line graphs. Further, full concordance was obtained by recalculating frequencies and forensic parameters with other established software from a published Han Chinese population.


Assuntos
Cromossomos Humanos X , Gráficos por Computador , Impressões Digitais de DNA , Genética Populacional , Repetições de Microssatélites , Software , Conjuntos de Dados como Assunto , Feminino , Frequência do Gene , Haplótipos , Humanos , Masculino , Reprodutibilidade dos Testes
11.
Int J Legal Med ; 133(4): 1043-1047, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30446817

RESUMO

Population genetic data for 21 X-chromosome markers (Alu insertions and STRs) are reported for two populations (rural and urban) in Salta province (north-western Argentina). New variants are described, confirming the complexity and variability of some markers in this set. Results reveal Salta populations harbor a high Native American component, despite their self-recognized European ancestry. Notwithstanding the high genetic similarity of both populations, the rural sample seems to have maintained a larger Amerindian legacy. Data further show these X-linked markers, especially STRs, are highly informative in Salta populations and, therefore, can contribute to the development of a local database for forensic purposes in north-western Argentina.


Assuntos
Cromossomos Humanos X/genética , Indígenas Sul-Americanos/genética , Polimorfismo Genético/genética , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Argentina , Frequência do Gene , Variação Genética , Genética Populacional/estatística & dados numéricos , Humanos
12.
Ann Hum Biol ; 46(7-8): 574-580, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31795774

RESUMO

Background: Guizhou province is located in southwest China with abundant genetic, linguistic and cultural diversity. The Bouyei is one of the 18 officially recognised minority groups in Guizhou, accounting for about 97% of the total Bouyei population in China. However, the genetic history and forensic characterisation of the Bouyei people is largely unknown due to a lack of genetic data.Aim: We aim to investigate genetic polymorphisms and forensic characterisation of the Guizhou Bouyei population, as well as the relationships between the Bouyei and other East Asian populations.Subjects and methods: We genotyped 19 X-STRs in 188 males and 165 females of Guizhou Bouyei using the AGCU X19 STR Kit. We estimated allele frequencies, forensic parameters and genetic distances between the Bouyei and other East Asian populations. We presented the genetic distances in a phylogenetic tree, an MDS plot and a PCA plot.Results: In Guizhou Bouyei individuals, we observed 216 alleles with corresponding frequencies ranging from 0.0019 to 0.6757. All of the six combined powers of PDm, PDf, MEC Krüger, MEC Kishida, MEC Desmarais and MEC Desmarais in allele diversity and haplotype diversity are larger than 0.99999995. We found genetic affinities among the Bouyei people and their geographical neighbouring populations in Guizhou, such as the Sui, Miao and Han.Conclusions: The highly polymorphic and informative forensic parameters of the 19 X-STRs in Bouyei people show the powerful potential of those markers in forensic identification and parentage tests. The genetic relationships of the Bouyei with other East Asian populations correspond well with geographic affiliations as well as linguistic classifications.


Assuntos
Cromossomos Humanos X/genética , Etnicidade/genética , Genótipo , Repetições de Microssatélites , Polimorfismo Genético , China , Feminino , Genética Forense , Humanos , Masculino
13.
Int J Legal Med ; 132(2): 405-408, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28868569

RESUMO

The analysis of 12 X-STR loci included in the Investigator® Argus X-12 kit was performed on a sample of 325 unrelated persons from Vojvodina Province, Republic of Serbia. No significant differences were observed in the allele frequencies in males and females. Heterozygosity values among the studied loci ranged from 67.62 to 94.28%. All loci in female individuals were consistent with the Hardy-Weinberg equilibrium test. The combined power of discrimination values in male and female individuals was 0.9999999994 and 0.999999999999999, respectively. The combined mean exclusion chance was 0.999998 in deficiency cases, 0.9999999977 in normal trio cases, and 0.9999994 in duo cases. Loci DXS10135 and DXS10101 were found to be most polymorphic. The haplotype diversity was found to be greater than 0.993 for all linkage groups. The exact test for pairwise linkage disequilibrium for the 12 loci in the male samples showed significant linkage disequilibrium for the DXS10103-DXS10101 and DXS10134-DXS10146 pairs of loci. The results from the current study confirmed that the panel of 12 X-STR loci is highly polymorphic and informative and can be implemented as a powerful tool in deficient paternity testing and kinship analysis, as well as a useful complement tool of autosomal short tandem repeats (STRs) in forensic investigation. Population differentiation analyses indicated significant differences in genetic structure between the Serbian population and the geographically and ethno-linguistically distant populations, while genetic homogeneity was present in populations with similar geographic origin.


Assuntos
Cromossomos Humanos X , Genética Populacional , Repetições de Microssatélites , Impressões Digitais de DNA , Feminino , Frequência do Gene , Haplótipos , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético , Sérvia
14.
Int J Legal Med ; 132(2): 409-413, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28868577

RESUMO

The X-chromosomal short tandem repeats (STRs) with more informative than autosomal STRs in some complicated biological relationships identification due to its specific mode of genetic transmission can be used as a complementary tool in forensic case practices. In this study, we presented the population genetic data of 19 X-STRs, consisting of DXS10174, DXS10075, DXS10079, DXS101, DXS10101, DXS10103, DXS10134, DXS10135, DXS10148, DXS10159, DXS10162, DXS10164, DXS6789, DXS6809, DXS7132, DXS7423, DXS7424, DXS8378, and HPRTB loci, in a sample of 235 individuals of Tibetan nationality from Sichuan province, Southwest China. All 19 X-STR loci were consistent with Hardy-Weinberg equilibrium. The results showed that the combined power of discrimination in females and males are 0.999999999999999999997 and 0.9999999999997, respectively. In addition, the mean paternity exclusion chances based on the formula of MECKrüger, MECKishida, and MECDesmarais as well as MECDesmarais Duo are 0.99999991, 0.9999999999924, 0.9999999999929, and 0.999999985, respectively. In summary, our findings suggested that the AGCU X19 kit can be considered to serve as a high polymorphic information tool for forensic identification and kinship testing in the Sichuan Tibetan population. Furthermore, population genetic structure investigation between Sichuan Tibetan population and other 19 populations using PCA, MDS, and phylogenetic tree illustrated that significant genetic difference was observed between the Sichuan Tibetan and Malay, as well as the Xinjiang Uyghur population.


Assuntos
Cromossomos Humanos X , Etnicidade/genética , Genética Populacional , Repetições de Microssatélites , Povo Asiático/genética , China , Impressões Digitais de DNA , Feminino , Frequência do Gene , Variação Genética , Humanos , Masculino , Análise de Componente Principal , Tibet/etnologia
15.
Int J Legal Med ; 132(4): 967-973, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28730502

RESUMO

This report identifies and characterizes 10 novel short tandem repeat (STR) loci on the human X chromosome, all of which are within a range of 1.1 Mb. These newly characterized loci were developed to aid in kinship assignment when the X chromosome is specifically required. The repeat DNA sequences were identified initially using data in GenBank and are located immediately upstream and downstream from the previously described locus DXS6807. Only those loci with seven or more observed alleles were used for further study resulting in the identification of 10 new loci. The distance between each pair of loci ranged from 24,998 to 244,701 bp with an average of approximately 110.8 kb. The number of observed alleles ranged from 7 to 30 for these 10 loci with a polymorphic information content ranging from 0.593 to 0.930. The LOD score from a pairwise linkage study ranged from 4.40 to 23.73, indicating that these 11 loci were highly linked, as expected. In line with standard forensic practice, all 11 loci can be amplified in one multiplex reaction, and comprehensive allelic ladders for all the loci have been constructed. These newly established 11 linked STR loci on the human X chromosome were found to be highly polymorphic and have the potential to aid in kinship testing where the X chromosome loci currently plays a role.


Assuntos
Cromossomos Humanos X/genética , Genética Forense/métodos , Repetições de Microssatélites , Feminino , Frequência do Gene , Loci Gênicos , Humanos , Desequilíbrio de Ligação , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético , Análise de Sequência de DNA
16.
Int J Legal Med ; 132(2): 361-371, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28547136

RESUMO

Recent progress in forensic genetics has introduced a number of closely located short tandem repeat (STR) markers on the X chromosome. Inevitably, dependencies arise that have to be accounted for. This paper will in detail explore the complex statistical interpretation of X-chromosomal STR markers, focusing on likelihood calculations. Specifically, we will investigate how the phase uncertainty of haplotypes comes into play in the statistical evaluations and what curious effects this phenomenon can have. The starting point is the different real cases where the weight of evidence has provided unexpected results that require further investigation in order to be fully understood. We will touch upon subjects such as association between alleles, recombinations, and mutations. The aim of this study is to facilitate a better understanding of the interaction between the concepts in addition to provide an understanding why good estimates of haplotype frequencies are crucial. The individual subjects have been discussed in other fields, whereas this study will focus on forensic applications where few studies have been conducted relating to the understanding of how these concepts interact.


Assuntos
Cromossomos Humanos X , Impressões Digitais de DNA , Haplótipos , Repetições de Microssatélites , Feminino , Genética Forense , Humanos , Funções Verossimilhança , Masculino , Modelos Estatísticos , Mutação , Linhagem , Polimorfismo de Nucleotídeo Único
17.
Int J Legal Med ; 131(6): 1523-1530, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28405752

RESUMO

Studies with X-STR loci show population genetic substructure, which makes necessary the characterization of such markers in the different geographical and/or ethnic populations. Therefore, this study assessed the distribution and forensic efficiency of an X-STR decaplex system in the population of the State of Mato Grosso, as well as analysed the population structure of this State based on the aforementioned system. All X-STR markers were in Hardy-Weinberg equilibrium and linkage equilibrium, and the DXS6809 was the most informative marker. The power of discrimination value in females and males was 0.99999999995 and 0.9999994, respectively. Analysis of molecular variance indicated 1.10% (p < 0.00001) of heterogeneity among Europeans, Africans, Brazilians and other Latin Americans, and in relation to such groups, the population of the State of Mato Grosso showed lower genetic variation when compared with the Brazilian group (-0.10%, p = 0.67327). The genetic distance analysis showed lower values of F ST (0.0004 ≤ F ST ≤ 0.00331), with non-significant p value (p > 0.00024), between the populations of Mato Grosso and Mato Grosso do Sul, Paraná and the Southeast region of Brazil (except for one sample of Rio de Janeiro). F ST values with significant p values (p ≤ 0.00024) were obtained between the population of Mato Grosso and Iberian, African and some Latin American populations. The X-STR decaplex system proved to be extremely useful in the population of the State of Mato Grosso, and the data obtained does not show the need for a specific forensic database for this State in relation to the Brazilian populations compared in this study, except for population of Rio de Janeiro.


Assuntos
Cromossomos Humanos X , Impressões Digitais de DNA/instrumentação , Genética Populacional , Sequências de Repetição em Tandem , Brasil , Feminino , Frequência do Gene , Variação Genética , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase , Grupos Raciais/genética
18.
Int J Legal Med ; 131(4): 975-977, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28101645

RESUMO

Application of X-STRs as complements of autosomal STR application in the forensic genetics has become a tendency for kinship testing, especially in deficiency paternity cases. Recently, a novel kit of 19 X-STR loci was developed, which permitted the analysis of 19 STR in the same PCR reaction, and these markers can be clustered into seven groups for the physical linkage. The objective of this study was to evaluate the allele and haplotype diversity of 19 X-STR loci in the Uygur (n = 220) and Tibetan nationality (n = 270) and to estimate the usefulness for complex kinship analysis. In the Tibetan and Uygur populations, a total of alleles of all loci were 188 and 212, with the allele frequencies ranged from 0.0037 to 0.5593 and from 0.0045 to 0.5409, respectively. Compared with previous studies, DXS10135 was the most polymorphic locus in the two population groups, whereas the least variant locus was DXS10164 in the Uygur population and DXS7423 in the Tibetan nationality. Haplotype diversity obtained in this investigation was greater than 0.9 across all LGs. This study indicated the new kit could be used as a supplementary tool in kinship testing in China. In addition, the data sets can be used as supplementary national X-STR references to enlarge the database.


Assuntos
Cromossomos Humanos X , Repetições de Microssatélites , Polimorfismo Genético , Etnicidade/genética , Frequência do Gene , Haplótipos , Humanos , Masculino , Reação em Cadeia da Polimerase
19.
Int J Legal Med ; 131(5): 1229-1233, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28243771

RESUMO

DNA testing using X-chromosomal short tandem repeat (X-STR) polymorphisms has been used in maternity/paternity and complex kinship cases. Analyses of repeat sequences, surveys on racial statistics, and development of practical applications for DNA testing continue to be reported. In this study, we identified four novel tetranucleotide STR loci located in the X chromosome, which is the basis of X-STR research. These four tetranucleotide STRs were located within 71 kb of the chromosome Xp22.3 region. Using sequence analysis of the structure of repeat sequences, we identified simple repeat sequences of TAAA, CTTT, TATC, and GATA with rare insertions. We then calculated forensic statistical parameters using base length analysis. In the Japanese population, the polymorphism information content was 0.597-0.687, power of discrimination in females was 0.829-0.884, and power of discrimination in males was 0.635-0.729. As these tetranucleotide STRs are closely linked, we conducted haplotype analysis and detected that three loci (LC149476, LC149479, and LC149480) were in linkage disequilibrium. We demonstrated that the simultaneous analysis of these loci may be useful in complex kinship cases. Because these four loci can be detected by multiplex PCR, the detection of alleles at these loci can be rapidly and easily achieved. We conclude that the X-STR loci detected in this study may be useful tools in complex kinship cases and may increase the reliability of genetic testing.


Assuntos
Cromossomos Humanos X , Repetições de Microssatélites , Polimorfismo Genético , Povo Asiático/genética , Feminino , Frequência do Gene , Haplótipos , Humanos , Japão , Desequilíbrio de Ligação , Masculino , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
20.
Int J Legal Med ; 131(4): 963-965, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27933412

RESUMO

The X-chromosome short tandem repeat (STR) loci are of particular interest for solving complex kinship and paternity cases. Here, we report the genetic data from 209 unrelated Bangladeshi individuals (102 males and 107 females) that were genotyped using the 12 X-chromosomal STR markers included in the Investigator® Argus X-12 kit (Qiagen). The 12 X-STR markers are located in four linkage groups (linkage group I: DXS10135, DXS10148, and DXS8378; linkage group II: DXS7132, DXS10079, and DXS10074; linkage group III: DXS10103, HPRTB, and DXS10101; and linkage group IV: DXS10146, DXS10134, and DXS7423). Allelic frequencies of the 12 X-STR loci and haplotype frequencies of the four linkage groups were investigated. No significant difference was observed in the allele frequencies of males and females. Distributions of heterozygosity were observed from 64.5 to 92.5% among the studied 12 X STR loci. DXS10135 and DXS10101 loci were found to be most polymorphic. For all the four linkage groups, the haplotype diversity was found to be greater than 0.986. A total of 95, 73, 66, and 74 haplotypes were observed in linkage groups I, II, III, and IV, respectively. Hardy-Weinberg equilibrium tests showed no significant deviation from expected values for all 12 loci (p > 0.05). The exact test for pairwise linkage disequilibrium for the 12 loci in the male samples did not show any significant linkage disequilibrium except the DXS10103 and DXS10101 loci after the p values were corrected by Bonferroni's correction for multiple testing (p > 0.05/66). A combined power of discrimination in male and female individuals were 0.999999998159791 and 0.999999999999993, respectively. The combined mean exclusion chance were 0.999997635 in deficiency cases, 0.999999996 in normal trio cases, and 0.999999178 in duo cases. The currently investigated Bangladeshi population showed significant differences when compared with previously reported X-STR data from other 12 populations. The results of the data analysis indicated that all the loci in the Investigator® Argus X 12 kit were fairly informative and might be useful in forensic application and kinship analysis in Bangladeshi population.


Assuntos
Cromossomos Humanos X , Variação Genética , Genética Populacional , Repetições de Microssatélites , Reação em Cadeia da Polimerase/instrumentação , Bangladesh , Impressões Digitais de DNA , Feminino , Frequência do Gene , Marcadores Genéticos , Humanos , Masculino
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