This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
BRCA 1 gene is located on chromosome 
Select and explain. 
A. 17p21, B. 17q21, C. 13p21, D. 13q21
B: 17q21
Answer: B: 17q21 
Explanation: A BRCA mutation is a mutation in either of the BRCA1 and BRCA2 genes, which are tumour suppressor genes. ... Women with harmful mutations in either BRCA1 or BRCA2 have a risk of breast cancer that is about five times the normal risk, and a risk of ovarian cancer that is about ten to thiy times normal.