The Association Between Endothelial Nitric Oxide Synthase Intron 4a/b Gene Polymorphisms And Coronary Artery Ectasia

ObjectiveTo investigate the correlation between polymorphism(intron 4a/b gene)of endothelial nitric oxide synthase(eNOS)gene and coronary artery ectasia(CAE)by detecting the polymorphisms of eNOS in patients with CAE.Thus,it aims to provide a theoretical basis for the pathogenesis of CAE,and hope to find a new direction in CAE treatment from the molecular biology perspective.MethodsThe study included 146 patients who underwent coronary angiography(CAG)in Tianjin First Central Hospital during Jan 2016 to Oct 2017,including 48 patients with CAE(CAE group),46 patients with CAD(CAD group)and 52 patients with normal coronary arteries(NCA group),whose age as well as gender were matched.All the patients'clinical data was recorded,such as gender,age,history of smoking,history of drinking,history of type 2 diabetes mellitus and hypertension,etc.Polymorphism chain reaction(PCR)method was applied in this study.The genotype distribution frequency of the three groups was confirmed by the law of Hardy-Weinberg genetic equilibrium.The differences of genotype,allele distribution and the relationship between eNOS 4a/b gene polymorphisms and involvement of coronary artery dilatation were compared.Logistic regression statistical analysis was used to explore the relationship between eNOS 4a/b gene polymorphisms and CAE.Result1?The results of the CAG showed that CAE was most frequently involved in a single artery(54.2%),followed by two branches(29.2%)and three branches(16.6%).The most commonly involved vessel was the right coronary artery(42.3%),followed by the left anterior descending artery(33.3%)and circumflex artery(24.4%).2?The results of genotype distribution in three groups showed that bb genotype was the most common,followed by ab genotype,while aa genotype was the least.The frequencies about genotype of aa,ab and bb in CAE group were 0.083,0.333 and0.583,respectively.The distribution about genotype frequencies in CAD group were0.065,0.304 and 0.63,respectively.And the frequencies in NCA group were 0.019,0.192 and 0.788,respectively.But there was no significant difference between the three groups(?~2=5.77,P=0.22).The allele frequencies of a and b were 0.25 and 0.75in CAE group,0.217 and 0.783 in CAD group,0.115 and 0.885 in NCA group.There was statistical difference between the three groups(?~2=6.41,P=0.04).By further comparison,there were statistical differences between CAE group and NCA group(P=0.013<0.05).While there was no statistical differences between CAE group and CAD group as well as CAD group and NCA group(P>0.05).3?There were no statistical differences in genotypes and allele frequencies of the patients with different involved vessels in CAE group(P>0.05).The distribution of genotypes and alleles in CAE patients with different degree of lesions were compared,and no statistical difference was found(P>0.05).4?A binary Logistic regression analysis between eNOS 4a/b gene polymorphisms and CAE was performed,the results showed that there was no statistically significant correlation between the aa genotype,ab genotype and aa+ab genotype and CAE(P>0.05).In order to get rid of the influences of gender,age,hypertension etc,multivariate logistic regression analysis was performed.The result still showed that there was no statistically significant correlation between the genotypes and CAE(P>0.05).Conclusions1?Compared with the NCA group,the distribution frequency of a allele was significantly increased in CAE group,but it was not considered as the genetic susceptibility factor of CAE.2?There was no statistical correlation between eNOS 4a/b gene polymorphisms and the numbers of vascular involvement in the patients with CAE.Also,no statistical correlation was found between eNOS 4a/b gene polymorphisms and the severity of vascular dilatation in the patients with CAE.3?There was no statistical correlation between eNOS 4a/b gene polymorphisms and CAE.