Hypertrophic Cardiomyopathy Caused By Arg723Gly Mutation In Cardiac Myosin-Binding Protein C Gene

1.To detect the situation of Cardiac myosin binding protein-C gene mutation in Chinese population of Shandong province with hypertrophic cardiomyopathy(HCM);2.To verify if there are differences between the Chinese people and foreigners in the incidence of Cardiac myosin binding protein-C gene mutation in patients with hypertrophic cardiomyopathy;3.To analysize the correlation between genotypes and phenotypes;4.To establish a method to diagnose hypertrophic cardiomyopathy pre-clinically at gene level.Methods:1.78 unrelated clinical patients with HCM were chosen for the study.After informed consent,a venous blood sample for extraction of DNA was obtained.In addition,100 healthy individuals were examined as normal controls; 2.High molecular weight DNA was extracted from peripheral blood lymphocytes of patients and controls with the SDS proteinase K method and phenol/chloroform extraction;3.The primers used for amplification of exon14--16,19,20,22,33 of Cardiac myosin binding protein-C gene were from adjacent intronic sequence.Protein coding exons14-16,19,20,22,33 of Cardiac myosin binding protein-C was amplified using polymerase chain reaction(PCR).The PCR products were examined by means of agar-gel electrophoresis to assay the quantity and specialty;4.Single strand conformation polymorphism(SSCP) method was used to detect possible gene mutations in the PCR products. Different conditions were used to enhance the sensitivity of the method including different polypropylene concentration,different proportion of PCR products and cushion fluid etc.Sequence the suspicious PCR products for exact mutant point;5. Perform clinical studies and examine the incidence of sudden cardiac death within the family. Results:1.We succeeded in amplifying the five exons of the 78 patients;2. All of the PCR products were examined by SSCP method through different conditions and vivid single strand belts have been got;3.By contrast with normal controls,we have found a mutation Arg723Gly in a HCM patient;4.By contrast to the other HCM patients,we couldn't find the particularity of the patient harboring the mutation.Conclusions:1.PCR-SSCP can be used properly to examine the Cardiac myosin binding protein-C mutation and can be pervaded widely;2.We have found a frame-shift mutation in a HCM patient;3.The incidence of mutations in gene encoding Cardiac myosin binding protein-C in HCM patients of Chinese population is much lower than what have been previously reported;4.The genotypes and phenotypes are not simply in according with each other;5.There is a long way to go to conquer this disease.