To explore the polymorphisms of T149C and T950C gene in osteoprotectin (OPG) promoter sites and the levels of serum OPG and soluble nuclear factor-ΚB receptor activator ligand (sRANKL) and the incidence of coronary heart disease (CHD). 528 patients in Tianjin suspected of CHD and underwent coronary angiography (CAG) who admitted to the department of cardiology of Tianjin Chest Hospital from April 2017 to December 2018 were enrolled. According to the CAG results, they were divided into two groups: CHD group (n = 302) and non-CHD group (n = 226). The gender, age, history of hypertension, family history of CHD, diabetes, levels of blood lipid parameters in serum and other clinical data of patients were recorded. The levels of serum OPG and sRANKL were measured by enzyme-linked immunosorbent assay (ELISA). T149C and T950C gene polymorphisms were analyzed by polymerase chain reaction-restriction endonuclease fragment length polymorphism (PCR-RFLP) methods. Hardy-Weinberg genetic balance test was performed for alleles. Binomial classification multivariate non-conditional Logistic regression method was used to analyze the relationship between T149C and T950C gene polymorphisms, serum levels of OPG and sRANKL and CHD. All patients were enrolled in the final analysis. The serum level of OPG in CHD group was significantly higher than that in non-CHD group (μg/L: 1.76±0.49 vs. 1.47±0.29, P < 0.01), the serum level of sRANKL was significantly lower than that in non-CHD group (ng/L: 342.14±121.38 vs. 376.63±108.66, P < 0.05). Logistic regression analysis showed that after adjusting for age, gender, blood lipid parameters, diabetes and other factors, the increase in serum OPG level was an independent risk factor for CHD [odds ratio (OR) = 1.995, 95% confidence interval (95%CI) = 1.935-2.066, P = 0.012]. PCR-RFLP results showed that TT, TC and CC genotypes were found in T149C and T950C of OPG promoter. According to Hardy-Weinberg equilibrium test, the polymorphisms of OPG T149C and T950C accorded with Hardy-Weinberg law, achieving genetic balance with representative of the population. The frequencies of TT, TC, CC and alleles T and C in T149C genotypes of non-CHD group were 53.5%, 42.9%, 3.6%, 75.0% and 25.0%, respectively, and they were 43.1%, 50.3%, 6.6%, 68.2% and 31.8%, respectively in CHD group. There were statistically significant differences in genotype and allele frequencies between the two groups (all P < 0.05). It was shown by Logistic regression analysis that the risk of CHD in TC+CC genotype of T149C was 1.86 of TT genotype (OR = 1.86, 95%CI = 1.24-2.78, P = 0.003). It was suggested that C allele might be a susceptible gene for CHD. In non-CHD group, the frequencies of TT, TC, CC, and alleles T and C in T950C genotypes were 39.8%, 46.5%, 13.7%, 63.1% and 36.9%, respectively. They were 39.4%, 43.4%, 17.2%, 61.1% and 38.9%, respectively in CHD group. There were no significant differences in genotype and allele frequencies between the two groups (all P > 0.05). Logistic regression analysis showed that TC+CC genotype of T950C was not related with CHD. The increased level of serum OPG was closely related with CHD and could be used as a risk factor for CHD. The cases carried OPG T149C TC+CC genotype might have the risk suffering CHD. C allele is might be a susceptible gene.
Read full abstract