RESUMO
To investigate the mutation site of pathogenic gene in patients with hypertrophic cardiomyopathy (HCM) and to analyze the relationship between the genotype and clinical phenotype. Methods: Targeted exon capture sequencing was conducted in a HCM proband for 30 coding exons related HCM gene by all exon amplification and high-throughput sequencing. Furthermore, Sanger sequencing was performed in other family member and in 200 healthy volunteers for verification. The familial investigation included in clinical presentation, physical examination, electrocardiogram and echocardiography. Results: There were 3/6 blood relatives carrying cardiac myosin-binding protein gene MyBPC3 G772A heterozygous mutation, the mutation site was at 258 amino acid of MyBPC3 as glutamic acid (Glu) was substitute to lysine (Lys), such mutation was not found in rest of family member and not in healthy volunteers. The onset of proband and her daughter was rather late, they had palpitation and chest tightness; echocardiography showed interventricular septum basal segment thickening (16-18) mm. Proband was complicating paroxysmal ventricular tachycardia, malignant arrhythmia and heart failure, the maximum pressure gradient of left ventricular outflow was 56 mmHg, which with the high risk for sudden death. Conclusion: Comprehensive gene test has been helpful for clinical stratification, early diagnosis and treatment. MYBPC3 site mutation c.G772A might be the pathogenic mutation in that specific HCM family.