Objective  This study aimed to investigate the prevalence and spectrum of the BRCA1/2 gene mutation in high-risk breast cancer cases among multiple ethnic groups in Xinjiang, China.

  Methods  A total of 68 high-risk breast cancer cases from Xinjiang were included in this study according to the following inclusion criteria: 12 hereditary predisposition to breast cancer (HBC) cases (at least one first- or second-degree relative with breast cancer), 4 hereditary predisposition to breast and ovarian cancer cases (at least one first- or second-degree relative with ovarian cancer), 25 early-onset breast cancer cases (onset age below 35 years), 10 bilateral breast cancer cases, and 17 triple-negative breast cancer cases (onset age below 45 years). Genomic DNA was extracted and relevant coding sequences were amplified by PCR. The entire coding BRCA1/2 genes were analyzed by DHPLC followed by DNA sequencing.

  Results  A total of six deleterious mutations were identified: three in BRCA1 and three in BRCA2. The prevalence of BRCA1/2 mutation in high-risk HBC was 8.8% (6/68). No significant difference was observed among the ethnic groups in terms of BRCA1/2 mutation prevalence.

  Conclusion  High-risk HBC cases had different BRCA mutation spectra from ethnic Chinese breast cancer cases in Xinjiang, China.