Abstract: Objective To investigate the prevalence of BRCA1/2 gene mutations among uygur and han sporadic breast cancer patients in Xinjiang Uygur Automous. Methods Polymerase chain reaction (PCR) and DNA sequencing was used to detect mutations of BRCA1(exons 2, 11(11A and 11B) and 20) and BRCA2 (exon 11) genes in the Paraffin imbedding tissues from 230 sporadic breast cancer patients(115 uygur and 115 han) in Xinjiang Uygur Automous. Results In the 230 cases of sporadic breast cancer patients, there were 16 cases of gene mutation (16/230，6.96%). 1 case of BRCA1 gene in 16 cases of mutations - 5382 locus mutation and 7 cases of new mutations. There was 2 germline mutation in exon 11 of BRCA2 gene. BRCA gene mutation detection rates of Uighurs and Han patients were 7.83% (9/115) and 6.09% (7/115). The onset age of mutations group were 50 or less. Mutations group of patients with amenorrhea(3) were less than whom were premenopausal(13) (P<0.05). Conclusion The results of this study show that the prevalence of BRCA1 mutations was significantly higher than BRCA2 in sporadic breast cancer patients of Xinjiang.

Key words: Sporadic breast cancer, BRCA1/2gene, Mutation, DNA seguencing