Correlation between polymorphism of ACE gene I/D and ACE2 gene A9570G and atrial fibrillation

Objective To investigate the correlation between the polymorphism of angiotensin converting enzyme(ACE) gene I/D and angiotensin converting enzyme 2(ACE2) gene A9570G and atrial fibrillation.Methods In chronological order of hospitalization,305 patients were selected and divided into two groups: atrial fibrillation group(148 cases) and control group(157cases without atrial fibrillation).The control group was matched with the atrial fibrillation group in terms of age,gender,and presence of left ventricular dysfunction,coronary heart disease,diabetes,and primary hypertension.The polymorphisms of the ACE gene I/D and ACE2 gene A9570G were genotyped with polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) and gene sequencing approach.Results There were no statistical differences between the atrial fibrillation group and the control group in genotype distribution and allele frequencies of the ACE gene I/D(P=0.841;OR=0.948,95% CI 0.680-1.322,P=0.755).Moreover,there was no significant difference among the different genotypes of ACE gene I/D in the left and right atrial dimensions(P=0.887 and P=0.664,respectively).In the male subgroup,there was no statistical difference in the ACE2 gene A9570G polymorphism between the two groups(OR=1.631,95% CI 0.880-3.023,P=0.119).However,in the subgroup of males with atrial fibrillation,the left and right atrial dimensions of subjects with G genotype(40.1±6.4 and 40.1±5.7mm,respectively) were larger than those with A genotype(37.0±4.4 and 36.5±4.4mm,respectively),indicating a statistical difference(P=0.028,P=0.010).In the female subgroup,there were no statistical differences between the atrial fibrillation group and the control group in the genotype distribution and allele frequencies of the ACE2 gene A9570G polymorphism(P=0.286;OR=1.415,95% CI 0.885-2.264,P=0.146).In the subgroup of females with atrial fibrillation,no significant difference was found in the left or right atrial dimension among the different genotypes of ACE2 gene A9570G polymorphism(P=0.924 and P=0.432,respectively).Conclusions No significant correlation exists between the genotype distribution and allele frequencies of ACE gene I/D and ACE2 gene A9570G polymorphism and atrial fibrillation.However,in males with atrial fibrillation,the G genotype in the ACE2 gene A9570G polymorphism may be a risk factor for the prediction of atrial enlargement.