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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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BRCA1 gene is located on chromosome:
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The correct answer is  Mutations in BRCA1 and BRCA2 are responsible for 80% to 90% of "single gene" familial breast cancers and about 3% of all breast cancers. BRCA1 is located on 17q21 BRCA2 is located on chromosome 13q12.