Sequence characterization of microvariant alleles at DYS627 and DYS458

Y chromosome short tandem repeats (Y-STRs) have been widely used in genetic applications and forensic casework. Recently, we found two intermediate alleles, the DYS627 allele 24.1 and the DYS458 allele 15.3, from Chinese Han population. The two allelic variants have not been recorded by the YHRD database. We have examined the molecular structure of these allelic variants by Sanger sequencing. The results showed that this intermediate allele at DYS627 was confirmed as 24.1, the sequence of which showed a base “A” insertion in the 13th repeat unit, and the intermediate allele at DYS458 was confirmed as 15.3, the sequence of which showed a base “G” deletion in the 12th repeat unit. This may be important for individual identification and paternal kinship testing. Besides, more allelic variants detected can be enriched in the Y-STR database.     

DYS391、DYS393基因座X染色体扩增对法医鉴定影响的探讨

目的探讨提高DYS391和DYS393基因座特异性扩增方法及两基因座的X染色体扩增产物对法医学鉴定结论的影响。方法DYS391和DYS393基因座采用PCR扩增、聚丙烯酰胺凝胶电泳结合银染进行分析。结果稀释模板DNA浓度和提高退火温度对提高此两Y染色体基因座特异性扩增并不明显。DYS391和DYS393的X染色体扩增产物对法医学鉴定结论有误导可能性。结论在法医学鉴定尤其是性别鉴定中应谨慎应用DYS391和DYS393基因座。     

DYS385检测方法的改进

目的建立检测DYS385的新方法。方法比较基因数据库(GDB)中推荐的引物和Schneider所设计的引物扩增DYS385的效果;在此基础上,以GDB推荐的引物作为外引物,Schneider所设计的引物作为内引物,通过调整内、外引物的浓度,优化扩增条件,建立DYS385的半巢式PCR体系。结果与常规方法相比,采用Schneider所设计的引物扩增DYS385,扩增片段缩短112bp,电泳分离的效果好,灵敏度提高2倍,达500pg;建立的半巢式扩增方法,能特异性扩增短片段,灵敏度提高20倍,达50pg。结论建立的DYS385半巢式扩增方法具有更高的特异性和灵敏度,适合法医学应用。     

中国北方汉族人DYS19基因座多态性及应用

调查了DYS19基因在中国北方汉人群体中的基因频率分布(0.013～0.516),观察到6个等位基因,各等位基因分布存在明显的地域性差异,并对陈旧、微量、降解的生物检材具有良好的适用性.     

DYS448基因座分型缺失分析

目的调查分析DYS448基因座分型缺失,为法医学提供有意义的数据。方法收集中国汉族5487名无关男性个体血样,其中4479份样本用Y-filerTM试剂盒,1008份样本应用Yfiler PlusTM试剂盒进行复合扩增,所有样本应用AGCU Y-24试剂盒复核;统计DYS448基因座出现基因分型缺失的概率。结果在5487名无关个体的Y-STR数据中,观察到35个个体的35种单倍型中DYS448基因座分型出现缺失,其中2个样本在其它基因座位同时出现多谱带。结论 DYS448基因座分型缺失率为0.637%,在Y-STR数据库与父系鉴定应用中应予以关注。     

Y chromosome STR haplotypes and allele frequencies in Illinois Caucasian, African American, and Hispanic males

POPULATION: Population: Illinois Caucasian ( n =117), Illinois African American ( n =218), and Illinois Hispanic ( n =68).     

Population data for a novel, highly discriminating tetra-local Y-chromosome short tandem repeat: DYS503

Population: Population samples for gene diversity studies were obtained from the Virginia Division of Forensic Science (bloodstains), Richmond, VA. Ninety-eight Caucasian and 100 African American samples were included in this study.     

Characterization of deletions in the DYS385 flanking region and null alleles associated with AZFc microdeletions in Koreans

Eight DYS385 allele size discrepancies and six DYS448 null types were detected among 708 Korean men when results of three in-house multiplex short tandem repeat (STR) systems were compared. The systems included both ordinary and reduced size amplicons. Sequence analysis revealed deletion mutations at two sites upstream of the DYS385 core repeats and deletion of the entire DYS448 locus. At DYS385, allele size differences were one or two repeats and were dependent on the primer set used for polymerase chain reaction (PCR) amplification. Location of the primer target sequence in a flanking region of the STR, distal or proximal to the deletion, determined allele size. Two widely used commercial kits amplify DYS385 so as to include the mutable sites. Arrangement analysis of sequence tagged sites demonstrated that the deletion patterns at DYS448 (and DYS464) were associated with arrangements of the azoospermia factor c gene (AZFc). The DYS448 deletion appears relatively frequent in Asians.     

A DYS438 null allele observed in two generations of a large family

Typing of Y-chromosomal STR loci using the AmpFISTR^® Yfiler kit showed a DNA profile lacking the DYS438 allele in an Austrian Caucasoid brother pair.Buccal swabs were collected from additional males of two generations and different branches of the family. All family members investigated did not show a DYS438 allele in their Yfiler profile. Using the Powerplex^® Y system an allele with dramatically reduced peak height was amplified. Subsequent sequencing of the DYS438 locus exhibited a transition upstream of the repetitive region.     

DYS393多态性分析及其法医学应用

探讨了Y-DNASTR基因座DYS393的多态性及其法医学应用价值,用变性PAGE结合荧光DNA自动测序仪分析及非变性PAGE,结合银染显示两种PCR扩增产物的方法,并调查了广州地区120例汉族无关男性个体DYS393等位基因分布状况;在此基础上,建立了DYS393和HumARA两基因座的复合扩增体系,结果显示DYS393基因座共检出4种等位基因,复合扩增体系可同时提供性别鉴定和个体识别的信息.     

A novel multiplex PCR system consisting of Y-STRs DYS441, DYS442, DYS443, DYS444, and DYS445

We have developed a new sensitive multiplex PCR system consisting of five male-specific and polymorphic tetranucleotide STRs--DYS441 (GDB: 10013873), DYS442 (GDB: 10030304), DYS443 (GDB: 10807127), DYS444 (GDB: 10807128), and DYS445 (GDB: 10807129) on the Y chromosome. Fifty pg DNA per 10 microL reaction volume was required for the correct typing of five STRs. Using this system, the five Y-STRs were correctly typed from blood and semen stains that had been stored for several years at room temperature.     

Phylogenetic evidence for multiple independent duplication events at the DYS19 locus

Duplication events at Y chromosome STR loci have been repeatedly described in human populations. DYS19 is probably the best known example and it exhibits duplicate state in individuals from all continents. Despite the large amount of available data, evolutionary relationship between DYS19 duplication-bearing chromosomes has not been so far investigated. We address the genealogical correlation among such chromosomes by analysing newly identified DYS19 duplicated Y chromosomes by SNP genotyping and microsatellite-based network analysis. SNP and network analysis show that DYS19 duplicated Y chromosomes associate with different Y chromosome lineages. These results indicate that DYS19 duplication occurred more than once during human evolution.     

Analysis of Y-STR loci in a population sample from northeast China

POPULATION: A total of 141 unrelated Chinese Han male individuals living in Liaoning in northeast China.     

Y-chromosomal STR haplotypes in two endogamous tribal populations of Karnataka, India

POPULATION: Approximately 5.0 mL of blood sample was collected from a total of 150 men belonging to two tribal populations of coastal Uttar Kannada district of Karnataka, with their informed written consent. Both the populations are endogamous and they belong to the Dravidian linguistic family. Halakki is a tribal group having a population size of c. 3383. They claim that they originally belong to Gujarat and Rajasthan, and migrated through Andhra Pradesh to Karnataka. Kunabhi is also a tribal population, c. 35,214 in number. They were hunters and gatherers but presently they practice agriculture.