Genetic variation of fifteen autosomal STR loci in a Manchu population from Jilin Province, Northeast China

Genetic diversity of 15 STR loci in Yunnan Va ethnic minority and the phylogenetic relationships with 26 other populations

BACKGROUND

The Va (also called "Wa") people are an ethnic minority living mainly in the southwest of Yunnan Province.

AIM

This study was conducted to obtain the genetic information and forensic statistical parameters of 15 autosomal short tandem repeat (STR) loci included in the AmpFlSTR^®Identifiler™ kit (Applied Biosystems, Foster City, CA) in the Yunnan Va population, with a view to enriching the genetic databases of the Chinese Va population.

SUBJECTS AND METHODS

A total of 508 unrelated Chinese Va individuals were genotyped with this 15 STR kit, the genetic polymorphisms and associated forensic parameters were calculated. The genetic relationships between Chinese Va and 26 other Chinese populations were also evaluated.

RESULTS

All of the STR loci reached the Hardy-Weinberg equilibrium after Bonferroni correction. A total of 159 alleles were observed with allele frequencies ranging from 0.000984 to 0.606299. The combined discrimination power (CDP) and the cumulative probability of excluding (CPE) of the 15 STR loci were 0.999 999 999 999 999 988 126 and 0.999 995 734, respectively. Our results indicated that the geographically adjacent or ethnically close populations showed a higher genetic affinity.

CONCLUSIONS

The results of this study will enrich the forensic databases of the Chinese Va population and could be applied in forensic analysis.

Systematic selections and forensic application evaluations of 111 individual identification SNPs in the Chinese Inner Mongolia Manchu group

Single nucleotide polymorphism (SNP) possesses a promising application in forensic individual identification due to its wide distribution in the human genome and the ability to carry out the genotyping of degraded biological samples by designing short amplicons. Some commonly used individual identification SNPs are less polymorphic in East Asian populations. In order to improve the individual identification efficiencies in East Asian populations, SNP genetic markers with relatively higher polymorphisms were selected from the 1,000 Genome Project phase III database in East Asian populations. A total of 111 individual identification SNPs (II-SNPs) with the observed heterozygosity values greater than 0.4 were screened in East Asian populations, and then, the forensic efficiencies of these selected SNPs were also evaluated in Chinese Inner Mongolia Manchu group. The observed heterozygosity and power of discrimination values at 111 II-SNPs in the Inner Mongolia Manchu group ranged from 0.4011 to 0.7005, and 0.5620 to 0.8025, respectively, and the average value of polymorphism information content was greater than 0.3978. The cumulative match probability and combined probability of exclusion values at II-SNPs were 7.447E^-51 and 1-4.17E^-12 in the Inner Mongolia Manchu group, respectively. The accumulative efficiency results indicated that the set of II-SNPs could be used as a potential tool for forensic individual identification and parentage testing in the Manchu group. The sequencing depths ranged from 781× to 12374×. And the mean allele count ratio and noise level were 0.8672 and 0.0041, respectively. The sequencing results indicated that the SNP genetic marker detection based on the massively parallel sequencing technology for SNP genetic markers had high sequencing performance and could meet the sequencing requirements of II-SNPs in the studied group.