Correlation Analysis And Functional Study Of CTSB Gene Promoter Polymorphisms And Dilated Cardiomyopathy Patients

Objective: The study of genetic variation in dilated cardiomyopathy,in full swing,has been found that cathepsin B plays a key role in dilated cardiomyopathy.However,the genetic studies on the cathepsin B gene promoter are still sufficient,and the role in cardiovascular disease has not been reported.In this study,the relationship was explored between the genetic variation of the CTSB gene promoter and the pathogenesis of DCM by identifying the single nucleotide sequence variation in the CTSB gene promoter in the DCM group and the control group.Methods: The clinical data of the patients with dilated cardiomyopathy and the control group were analyzed by a case-control study method,and then DNA was extracted from the blood of the subjects,and PCR amplification was performed using the designed primers.Construction of a dual-luciferase reporter gene for functional analysis of DNA sequence variants.Finally,the binding sites of transcription factors predicted to be affected by DSVs were analyzed by the TRANSFAC database,and the binding effects of DSVs to transcription sites identified in DCM patients were found and validated by in vitro electrophoretic mobility assay（EMSA）.Finally,various statistical analysis methods were used to analyze the relationship between SNPs and DCM.Results: A total of 394 subjects were included in the study,including DCM group（n = 142）and control group（n = 252）.Whole blood was collected from all subjects,and c DNA was extracted and amplified by PCR technology.Sequencing revealed 2 SNPs related to the occurrence of DCM in the CTSB gene promoter region,g.4803T>C（rs1293312）and g.4954T>A（rs942670850）.Then,relevant statistical analysis was performed,including allele and genotype frequencies between DCM patients and controls,five-gene genetic model and haplotype analysis,and SNP-SNP interaction analysis,and P<0.05 was considered statistically significant.It was found that these two SNPs significantly reduced the transcriptional activity of the CTSB gene promoter.Finally,by comparing the TRANSFAC database,it was found that both SNP sites affect the binding of transcription factors,which was also confirmed by EMSA experiments.Conclusion: This study found that the genetic variation sites g.4803T>C（rs1293312）and g.4954T>A（rs942670850）in the CTSB gene promoter can be used as low-frequency influencing factors to affect the prevalence of DCM by participating in apoptosis.