Profiling of the germline mutation BRCA1 : p.Ile1845fs in a large cohort of Han Chinese breast cancer

Background Breast cancer is a one of the malignant carcinomas partially caused by genetic risk factors. Germline BRCA1 gene mutations are reportedly associated with breast cancers. Identification of BRCA1 mutations greatly improves the preventive strategies and management of breast cancer. The aim of our study was to investigate the frequency of the deleterious BRCA1 : p.Ile1845fs variant in breast carcinomas, as well as the correlation between p.Ile1845fs variant with clinicopathological parameters and clinical outcomes. Results A total of 23,481 clinically high-risk patients with breast cancer and 6489 healthy controls were recruited for p.Ile1845fs variant sequencing (either sanger or next generation sequencing). We identified 94 breast cancer patients (0.40%, 94/23481) as well as 11 healthy controls (0.17%, 11/6489) carried p.Ile1845fs variant. BRCA1 : p.Ile1845fs variant showed a higher frequency in patients with TNBC molecular typing (20.21%, 19/94) and family history (37.23%, 35/94) compared with non-carriers ( P = 3.62E-6 and 0.034, respectively). According to our data, we advanced the frequency of p.Ile1845fs variant and we confirmed that BRCA1 : p.Ile1845fs variant was associated with increased risk of breast cancer (OR = 2.36, 95%CI = 1.26–4.89, P = 0.004). Conclusions BRCA1 : p.Ile1845fs variant was a frequently pathogenic mutation in breast cancer in Han Chinese women and our data may be helpful for diagnosis and therapy of breast cancer.