Dilated cardiomyopathy (DCM) is the most common cardiomyopathy leading to heart failure. The most frequent genetic cause of familial DCM involves mutation in which gene?

• A Myosin heavy chain (MYH7) mutations causing hypertrophic cardiomyopathy
• B Titin (TTN) — giant sarcomeric protein mutations accounting for ~25% of familial DCM ✓
• C Desmoplakin (DSP) causing arrhythmogenic right ventricular cardiomyopathy
• D Alpha-galactosidase A (GLA) causing Fabry disease cardiomyopathy

Explanation

Titin (TTN) encodes the largest human protein and forms the elastic filament framework of the sarcomere; truncating TTN mutations account for approximately 25% of familial DCM cases, making it the most common genetic cause. MYH7 mutations (beta-myosin heavy chain) predominantly cause HCM. Desmoplakin mutations cause ARVC. Fabry disease is an X-linked lysosomal storage disorder causing hypertrophic cardiomyopathy.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.