Hypertrophic cardiomyopathy

Area of Science:

• Cardiology
• Genetics
• Molecular Biology

Background:

• Hypertrophic cardiomyopathy (HCM) is a multigenetic cardiac disease.
• It typically follows an autosomal dominant inheritance pattern with incomplete penetrance.
• HCM is primarily caused by mutations in genes encoding sarcomeric contractile proteins.

Purpose of the Study:

• To review the genetic basis of hypertrophic cardiomyopathy.
• To identify genes associated with sarcomeric and non-sarcomeric proteins implicated in HCM.
• To highlight the complex genetic landscape of HCM.

Main Methods:

• Literature review of genetic mutations associated with hypertrophic cardiomyopathy.
• Analysis of mutations in genes encoding thick filament proteins (e.g., beta myosin heavy chain).
• Analysis of mutations in genes encoding thin filament proteins (e.g., cardiac actin, troponins, tropomyosin).
• Inclusion of mutations in sarcomeric cytoskeletal proteins (e.g., titin) and non-sarcomeric proteins.

Main Results:

• Mutations identified in genes for thick filament proteins: beta myosin heavy chain, myosin light chains, and cardiac myosin binding protein-C.
• Mutations identified in genes for thin filament proteins: cardiac actin, cardiac troponin T, cardiac troponin C, cardiac troponin I, and alpha-tropomyosin.
• Mutations in the sarcomeric cytoskeletal protein titin are also implicated.
• Mutations in non-sarcomeric proteins contribute to non-pure forms of HCM.

Conclusions:

• Hypertrophic cardiomyopathy results from mutations in a wide array of sarcomeric protein genes.
• Genetic heterogeneity extends to non-sarcomeric proteins, contributing to diverse clinical presentations.
• HCM is a complex cardiac disease with varied genetic underpinnings and clinical features.