BRCA2 and Familial prostate cancer: Currently, the main causes of prostate cancer are genetic factors (BRCA1 or BRCA2 mutation) [3], environmental factors (serum As and Zn levels) [4], dietary factors (red meat, high fat) [5], age, family history [5], etc. Prostate cancer may be asymptomatic in the early stage, and the clinical symptoms of advanced patients are mainly urinary retention and back pain [6].