Analysis of beta 1 and beta 2-adrenergic receptors polymorphism in patients with apical ballooning cardiomyopathy

OBJECTIVE: The aim of our study was to analyse the frequency of beta1 and/or beta2 adrenergic receptor polymorphisms in patients with takotsubo cardiomyopathy (TTC). METHODS AND RESULTS: beta1 and/or beta2 adrenergic receptor polymorphisms in 61 patients with TTC were compared with 109 controls. The beta1 adrenoreceptor (amino acid position 389) genotype frequencies were significantly different in the two groups; assuming a recessive model for the allelic variant coding for Arg on this position, the odds ratio was 3.14, 95% Cl 1.55-6.37 (P = 0.0015). The beta2 adrenoreceptor amino acid position 27 genotype was significantly different and assuming a recessive model for the allelic variant coding for Gln on this position, the odds ratio was 0.29, 95% Cl 0.12-0.74 (P = 0.009). CONCLUSIONS: This study showed for the first time an association between TTC phenotype and beta1 adrenoreceptor gene polymorphisms. Beta adrenoreceptors gene polymorphisms are probably disease modifiers, and any risk estimate should be based on a combination of genotypes and on interactions with other genes and environmental features.