The renin-angiotensin system genetic polymorphisms and rheumatic mitral valve disease.

Objective: Angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism, angiotensinogen (AGT) gene polymorphism and angiotensin II type 1 receptor (AT1R) polymorphism in relation to rheumatic mitral valve disease were examined in a case-control study to investigate possible relationships between these gene polymorphisms and rheumatic mitral valve disease in patients undergoing mitral valve replacement (MVR).

Methods: A total of 50 patients with rheumatic mitral valve disease and undergoing MVR was compared with 50 normal, and age- and sex-matched control subjects. ACE I/D, AGT gene M235T and AT1R-adenine/cytosine 1166 (A1166C) genotype polymorphisms were identified by polymerase chain reaction (PCR) -based restriction analysis.

Results: ACE I/D polymorphism differed significantly between the groups. The control group mostly represented the heterozygote ID allele (74%), while the MVR group showed frequencies of 60% for the homozygote DD and II alleles. MM homozygote frequency was significantly greater in controls, but TT homozygote frequency was significantly greater in the MVR group. AT1R-A1166C genotype polymorphism also differed significantly between groups; the MVR group had 73.7% of the AC heterozygote allele, while controls had 64.4% of the AA and 66.7% of the CC homozygote alleles.

Conclusions: These results provided evidence of an association between ACE I/D polymorphism, M235T polymorphism and AT1R-A1166C genotype polymorphism and rheumatic mitral valve disease.