Sequence Analysis Of Y-STR DYS719 And DYS439 Loci And Their Genetic Polymorphism Among Shanxi Han Population

Objective To obtain the allele frequency of the two Y-STR loci (DYS719&DYS439) in Shanxi Han ethnic group ,and discuss the possibility of applying the two Y-STR loci to forensic casework.Methods EDTA-blood specimens were collected from 120 unrelated males in Han population in Shanxi. Different tissues of one corpse were analyzed including heart, liver , splen, lung, kidney, muscle and skin. The blood of 20 females were collected as control. Fifteen father-offspring pairs were investigated. All blood-specimens were anticoagulated with EDTA ,the Genomic DNA was extracted via method of phenol-chloroform.We choosed two Y-STR loci DYS719 and DYS439 from GDB,and amplified with PCR,the products were analysised by agarose gel electrophoresis and 8% non-denaturing polyacrylamide gel electrophoresis followed by silver-staining. Each allele of the DYS719 and DYS439 loci were sequenced and the allele ladders were constructed. Alleles of the Y-STR loci were nominated according to recommendations of the International Society of Forensic Genetics. The core repeats and their repeating numbers of these alleles were confirmed by sequencing.Results The results show that the DYS719 locus consists of repeats of a core sequence aat, five alleles were found,they are named 11,12,13,14,15,respectively with the allele frequency of 0.0833,0.1333,0.2167,0.4167,0.1500, the genetic diversity is 0.7322, and probability of discrimination power and probability of exclusion were both 0.7322. The DYS439 locus consists of repeats of a core sequence ctat ,four alleles were found , they are named 10,11,12,13,with the frequency of 0.1250,0.3833,0.3250,0.1667, the genetic diversity is 0.7040, and probability of discrimination power and probability of exclusion were both 0.7040. PCR products were not found in female DNA. The analysis of 15 father/son pairs have detected no mutation at the two loci. Different tissue from one corpse also has the same allele in the two Y-STR loci, shows that the two Y-STR loci have a good tissue oneness.Conclusion These results indicate that the DYS719 and DYS439 loci are high genetic polymorphic, the haplotype diversity shows good probability of discrimination power and high probability of exclusion. They are to be useful genetic markers in forensic science and human genetics research.