Association between the angiotensin-converting enzyme (insertion/deletion) and angiotensin II type 1 receptor (A1166C) polymorphisms and breast cancer among Brazilian women

INTRODUCTION: We evaluated the association between components of the renin-angiotensin system and the development of breast cancer in a case-control study by means of angiotensin-converting enzyme (ACE) insertion/deletion (I/D) and angiotensin II type 1 (AT( 1))-receptor A1166C polymorphisms. METHODS: Genotyping was performed by PCR-RFLP (restriction fragment length polymorphism) or PCR (polymerase chain reaction) using genomic DNA extracted from buccal cells of subjects with (101 cases) or without (307 controls) breast cancer. RESULTS: The frequencies of genotypes for ACE were: DD, ID and II (in %: cases: 60; 20; 20; controls: 46; 37; 17; p=0.019, chi(2)); and for AT(1)receptor were:AA,AC and CC (in %: cases: 65; 30; 5; controls: 51; 44; 5; p=0.114, chi( 2)).The results suggested that the A1166C polymorphism was not associated with breast cancer risk. On the other hand, for the ACE (I/D), there seemed to be different risks for cancer between cases and controls. CONCLUSIONS: The ID genotype was less frequently associated with the disease than were the DD or II; that is, women with the ID genotype were 3.1 times less likely to develop breast cancer than those with the other genotypes.The ID genotype might be protective against breast cancer and the ACE (I/D) polymorphism a possible target for developing genetic markers for breast cancer.