Fibrillin-1 gene polymorphism and risk of mitral valve disease

71İNGİLİZCE ÖZET (SUMMARY)FIBRILLIN-1 GENE POLYMORPHISM AND RISK OF MITRAL VALVE DISEASEBACKGROUND: MVP (OD pattern for familiar cases, the role of FBN genetic variant in theMVP has locally been studied), rheumatic carditis (the mitral valve is the primary focus ofendocardial involvement, but genetic data isn?t found about different involvements of mitralvalve in the rheumatic carditis), and connective tissue diseases such as MFS (OD pattern,mutation in the FBN1 gene on chromosome 15) and EDS (mutations in collagen gene), themost common anomalies of the mitral valve apparatus throughout childhood. FBN is one ofthe structural components of the elastin-associated microfibrils found in the mitral valve.AIM: A case-controlled study has performed to investigate the relationship between FBN1gene polymorphisms and risk of mitral valve disease and evaluate of genotype and phenotypecorrelation in the patients.METHODS: Thirtyseven patients with MVP, 40 patients with rheumatic carditis diagnosedby clinically evaluation and echocardiography and 59 age- and sex-matched normal controlswere studied. Polymorphisms of exon 50, intron 52 and 56 of the FBN1 were identified byPCR-based restriction analysis.RESULTS: There was significant difference in the distribution of FBN1 intron 56 genotypes(p = 0.001) and allelic frequency (p = 0.021) between the cases and controls in favor of healtychildren. A significant difference was not seen in genotype distribution or allelic frequencybetween the cases and controls for neither FBN1 exon 50 polymorphism nor intron 52polymorphism (p = 0.198 and 0.738, respectively). There was not genotype and phenotypecorrelation between mild/moderate cases and severe cases with mitral valve disease for FBN1exon 50, intron 52 or intron 56 polymorphisms.CONCLUSION: Patients with mitral valve disease (MVP, connective tissue diseases orrheumatic carditis) have higher frequencies of FBN1 intron 56 GC genotypes. Healty childrenhave higher frequencies of FBN1 intron 56 CC genotypes. We speculate that the higherfrequency FBN1 intron 56 G allel, the more increase in the risk of mitral valve disease.Key words: Mitral valve disease, fibrillin-1, mitral valve prolapse