Genetic polymorphisms in 16 X-STR loci analyzed in the She population from Zhejiang Province, China

Forensic characterisation and polymorphism analysis of 16 X-chromosomal STRs in the Jining Han population in Eastern China

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.

Genetic polymorphisms of 16 X-STR loci analyzed in the Han population of Yunnan Province, Southwest China

To investigate the genetic diversity and forensic identification efficiency of X-chromosomal short tandem repeats (X-STRs) in the Yunnan Han population, 16 X-STRs in 415 Yunnan Han individuals (247 males and 168 females) were studied. A total of 137 alleles were detected, and all loci in the Yunnan Han population were highly polymorphic. The combined discrimination of males (PDm) and females (PDf) was 0.9999997769115 and 0.999999999999999999996, respectively. Interpopulation comparisons between the Yunnan Han population and 21 other populations showed that the evolutionary relationships between different groups with the same ethnic group or nearby geographic origins were closer. This study provides the first data on X-STR genetic polymorphisms in the Yunnan Han population and enriches the X-STR database for the Chinese Han population.

Forensic genetic polymorphisms of 16 X-STR loci in the Yunnan Miao population and their relationship to other Chinese groups

Allele frequencies for 16 X-chromosomal STR (X-STR) loci were obtained from a sample set of 440 unrelated Yunnan Miao individuals in China. A total of 117 alleles were observed in this group, with allele frequencies ranging from 0.0016 to 0.7565. The most informative marker for the studied population was DXS10134, with a polymorphism information content (PIC) of 0.8499, and the least polymorphic locus was DXS6810 (PIC = 0.3071). The power of discrimination (PD) varied from 0.4046 (DXS6800) to 0.8642 (DXS10134) in males and from 0.6188 (DXS6800) to 0.9673 (DXS10134) in females. The combined PDM and PDF were 0.999999989975990 and 0.999999999999949, respectively. The combined MECD and MECT were 0.999983301904059 and 0.999999915883733, respectively. Furthermore, population genetic structure investigation between the Yunnan Miao and 20 other populations using principal component analysis (PCA), multidimensional scaling plot (MDS), and neighboring-joining (NJ) phylogenetic tree analyses illustrated significant genetic difference between the Yunnan Miao and the other populations. This study is the first to provide X chromosome genetic polymorphism data of the Miao population in Yunnan Province and can be used as a supplementary reference to enrich the national database.