This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Breast, Subject name: Surgery
[{'content': 'Most common Familial Breast cancer gene: \nSelect and explain. \nA. BRCA1, B. BRCA 2, C. Li-Fraumeni syndrome, D. STK 11', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) BRCA 1(Ref Sabiston 20th Edition 832)* Hereditary breast cancer - 5-10%# BRCA1 - 45% (MC hereditary Breast cancer)# BRCA2 - 35%# P53(Lifraumeni) - < 1%# Peutz jeughers, Cowden disease, Muir torre syndrome, Ataxia telangiectasia all less than 1% each.', 'role': 'assistant'}]