Study On The Polymorphisms Of DYS390, DYS391 And DYS393 In Han Population In Taiyuan And Their Application In Forensic Medicine

Objective To establish a complex PCR method and to investigate the genetic polymorphism and population difference of three loci on Y-chromosome, so as to provide a database for forensic medicine casework.Methods EDTA-blood specimens were collected from 163 unrelated males in Han population in Taiyuan. Different tissues of one corpse were analyzed including blood, muscle, liver and kidney. 20 father-offspring pairs were investigated. 20 female's blood were collected. DNA was extracted by TKM1 method and Chelex-100 method. Three loci (DYS390, DYS391 and DYS393) on Y-chromosome were amplified by a complex PCR. The PCR amplification products were analyzed by vertical denaturing polyacrylamide gel electrophoresis followed by silver staining. The core repeats and their repeating numbers of these alleles were confirmed by sequencing. A direct calculation and the Fisher's test were applied to our data.Results The products amplified by a complex PCR method were clarity. 5, 6 and 7 alleles were observed in loci DYS390, DYS391 and DYS393 respectively, the gene diversity (GD) values are 0.70584, 0.44760 and 0.56282 respectively. Haplotype frequency date of 37 different types were obtained. Allele frequency comparisons with other Han population samples analyzed for the markers of DYS390 and DYS391 showed a substantial similarity. However the DYS393 marker showed a significant difference when our data were compared to samples from Shenyang area. Three markers showed heterogeneity between populations with a statistically significant difference when our data were compared to white people samples. The typing results of different tissues from one individual were identical. The amplified products of female's samples were negative. Mutations were not found from 20 father-offspring pairs.Conclusion The complex PCR is a rapid and simple method for forensic medicine casework. The three Y-STR loci are very suitable to forensic medicine analysis and paternity test.