Abstract: The insertion/deletion polymorphism of the serotonin transporter-linked promoter region ( 5-HTTLPR) was studied using the polymerase chain reaction ( PCR) method in Xinjiang Uygur, Kazak, and Mongol ethnic groups. The results showed that there were no significant differencies in the distributions of the 5-HTTLPR genotype and allele frequencies among the three ehhnic groups. It should be noted that the short allele S had a higher frequency. X2 tests indicated that their distribution of genotypes was consistent with theHardy-Weinberg equillibrium( P > 0.05) . Statistical analysis gave the results: Observed heterozygosity (Hobs) , expected heterozygosity ( Hexp ) and polymorphism information of 5-HTTLPR from the Uygur ethnic group were 0.4167, 0.4845 and 0.3759; and those from Kazak ethnic group were 0.4141, 0.4338 and 0.3396; and those from Mongol ethnic group were 0.4639, 0.4386 and 0.3425. These results provide important group genetics information for forensic identification, anthropological and disease association studies.

Key words: 5-HTTLPR; Polymorphism; Uygur; Kazak; Mongol