Forensic features and phylogenetic structure survey of four populations from southwest China via the autosomal insertion/deletion markers.

ABSTRACT

Insertion/Deletion (InDel) polymorphisms, characterized by their smaller amplicons, reduced mutation rates, and compatibility with the prevalent capillary electrophoresis (CE) platforms in forensic laboratories, significantly contribute to the advancement and application of genetic analysis. Guizhou province in China serves as an important region for investigating the genetic structure, ethnic group origins, and human evolution. However, DNA data and the sampling of present-day populations are lacking, especially about the InDel markers. Here, we reported data on 47 autosomal InDels from 592 individuals from four populations in Guizhou (Han, Dong, Yi, and Chuanqing). Genotyping was performed with the AGCU InDel 50 kit to evaluate their utility for forensic purposes and to explore the population genetic structure. Our findings showed no significant deviations from Hardy-Weinberg and linkage equilibriums. The combined power of discrimination (CPD) and the combined power of exclusion (CPE) for each population demonstrated that the kit could be applied to forensic individual identification and was an effective supplement for parentage testing. Genetic structure analyses, including principal component analysis, multidimensional scaling, genetic distance calculation, STRUCTURE, and phylogenetic analysis, highlighted that the genetic proximity of the studied populations correlates with linguistic, geographical, and cultural factors. The observed genetic variances within four research populations were less pronounced than those discerned between populations across different regions. Notably, the Guizhou Han, Dong, and Chuanqing populations showed closer genetic affiliations with linguistically similar groups than the Guizhou Yi. These results underscore the potential of InDel markers in forensic science and provide insights into the genetic landscape and human evolution in multi-ethnic regions like Guizhou. Key points InDel markers show promise for forensic individual identification and parentage testing via the AGCU InDel 50 kit.Genetic analysis of Guizhou populations reveals correlations with linguistic, geographical, and cultural factors.Guizhou Han, Dong, and Chuanqing populations showed closer genetic affiliations with linguistically similar groups than the Guizhou Yi.