Abstract: Objective To investigate the genetic polymorphisms of 23 autosomal short tandem repeats（STR）loci in Xinjiang Kazakh population, and explore the population genetic relationships and evaluate its application value on forensic medicine. Methods The DNA of 550 unrelated individuals in Xinjiang Kazakh population were amplified using HuaxiaTM Platinum kit, and the PCR products were analyzed by electrophoresis through 3500XL genetic analyzer. The fragment sizes of alleles were analyzed subsequently by GeneMapper ID-X v1.4. Allele frequencies and forensic genetic parameters of 23 STR loci were statistically analyzed and compared with the available data of other populations from different races and regions. Results The power of discrimination(DP), and polymorphic information content(PIC) ranged from 0.8206 to 0.9879, 0.5888 to 0.9200. The total discrimination power and cumulate probability of exclusion were 1-9.2942×10-29 and 1-6.9503×10-11, respectively. Comparing with 23 reference populations, the genetic distance (Nei’s DA) between Xinjiang Kazakh in this study and Xinjiang Hotan Kazakh in database was the smallest(0.0044), while it was relatively larger between Xinjiang Kazakh and Tibet Tibetan (0.0333). Conclusions The results show that the 23 STR provided highly polymorphic information and forensic efficiency for forensic individual identification and paternity testing. The study of genetic diversity among different populations is useful in research of their origins, migrations and their relationships.

Key words: autosomal short tandem repeats, Xinjiang Kazakh, Neighbor-Joining tree, Genetic Relationships