Qiguang Tong

Mutation Spectrum in a Large Cohort of Unrelated Chinese Patients With Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HC) is a hereditary heterogeneous cardiovascular disorder. Existing data have been of predominantly Caucasian samples, and a large study is needed in Chinese population. The present study was intended to explore the genetic basis and clinical characteristics correlated with different genotypes in a large cohort of Chinese patients. Direct gene sequencing of β-myosin heavy chain (MYH7), myosin binding protein-C (MYBPC3), and cardiac troponin T (TNNT2) was performed in 136 unrelated Chinese HC patients. Clinical evaluations were conducted. In total, 32 mutations were identified in 36 patients (27%), including 10 novel ones. Distribution of mutations was 56% (MYBPC3), 31% (MYH7), and 13% (TNNT2), respectively. Double mutations were identified in 3% patients. The occurrence of HC-associated sarcomeric mutations was associated with an earlier age of onset, increased left ventricular hypertrophy, a higher incidence of syncope, previous family history, and sudden cardiac death. No statistical difference was identified in patients carrying MYBPC3 and MYH7 mutations with regard to clinical characteristics and outcomes. Patients with double mutations were associated with malignant progression in the study. In conclusion, MYBPC3 is the most predominant gene in HC. Multiple mutations are common in MYH7, MYBPC3, and TNNT2. The present study suggests a large diversity of HC and a prognostic role of genotype.

GW24-e1791 Mutation spectrum in a large cohort of unrelated Chinese patients with hypertrophic cardiomyopathy

Objectives Hypertrophic cardiomyopathy (HC) is a hereditary heterogeneous cardiovascular disorder. Data published to date was mainly in Caucasians and large study is needed in Chinese population. We were aimed to explore the genetic basis and the clinical characteristics correlate with different genotypes in a large cohort of Chinese patients. Methods Direct sequencing of β-myosin heavy chain (MYH7), myosin binding protein-C (MYBPC3) and cardiac troponin T (TNNT2) genes was performed in 136 unrelated Chinese HC patients. Clinical evaluation was assessed in all patients. Results In total, 32 mutations were identified in 36 patients (27%), including 10 novel ones. Distribution of mutations was 56% (MYBPC3), 31% (MYH7) and 13% (TNNT2). Double mutations were identified in 3% patients. The occurrence of HC-associated sarcomeric mutations were associated with an earlier age of onset, increased left ventricular hypertrophy, a higher incidence of syncope, family history and sudden cardiac death. No statistical difference was identified in patients carrying MYBPC3 and MYH7 mutations with regard to the clinical characteristics and outcome. Patients with double mutations were associated with malignant clinical process in the study. Conclusions In conclusion, MYBPC3 is the most predominant gene. Multiple mutations were common in MYH7, MYBPC3 and TNNT2. This study suggested the diversity of HC and a prognostic role of genotype.