A preliminary study showing no association between methylation levels of C3 gene promoter and the risk of CAD

OBJECTIVE: Coronary artery disease (CAD) is a multi-factor disease. Complement component 3 (C3) plays an important role in the development of CAD. The present study investigated the association between DNA methylation status of C3 gene promoter and the risk of CAD. METHODS: One hundred CAD patients and 1 hundred age-and gender- matched controls were recruited in current study. Methylation levels in CpG island in C3 promoter were determined by the method of bisulfite amplicon sequencing. RESULTS: Methylation levels of four CpG sites in C3 promoter were measured. There were no significant difference in methylation level of each CpG site between CAD patients and controls. Average methylation rate was also calculated. No significant difference in average methylation rate was observed between CAD and control groups. Stratified analyses based on EH, DM and smoking status were carried out, no significant association between C3 promoter methylation levels and the susceptibility of CAD was observed. Furthermore, seven haplotypes were established and no significant difference in haplotypes was observed between CAD and control groups. However, our study showed that C3 DNA methylation levels were positively associated with LDL-C levels. CONCLUSION: The present study showed no association between methylation levels of C3 promoter and the risk of CAD. However, the methylation levels might be related to LDL-C levels. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12944-018-0949-4) contains supplementary material, which is available to authorized users.