Abstract: Objective To analyze the allele frequencies of 6 STR loci (D12S358,D12S1675, D12S1663, D12S1697, D12S16725 and D12S1613) on chromosome 12 among KBD patients and residents in the KBD and non-KBD areas. Methods EDTA-blood samples were collected from 146 unrelated Chinese Han individuals in Shaanxi Province including 57 KBD patients, 48 control subjects living in the Kashing-Beck disease(KBD) area and 48 in the non-KBD area. The DNA samples were extracted and amplified by PCR, and the PCR products were analyzed by ABI 3100 Genetic Analyzer. Results In KBD patients, the allele number for the 6 STR loci (D12S358,D12S1675, D12S1663, D12S1697, D12S16725 and D12S1613) was 7, 7, 7, 10, 12 and 8, and the genotype number were 13, 12, 9, 17, 19 and 10, respectively; in the residents in KBD area, the allele number was 7, 5, 7, 9, 13 and 9, and the genotype number 12, 10, 12, 19, 16 and 8; in residents in non-KBD area, the allele number was 7, 5, 5, 12, 8 and 9, and the genotype number 17, 16, 8, 22, 14 and 8. There were significant differences in the allele frequencies in the D12S1725 loci between KBD patients and residents living in KBD area (P=0.0119) and the non-KBD area (P=0.0050), but no significant difference in other 5 loci among the 3 groups. Conclusion KBD patients have significantly different allele distribution patterns in the D12S1725 loci from the control subjects.