Dilated cardiomyopathy (DCM) is the most common cardiomyopathy worldwide. The most common identifiable genetic cause involves mutations in which protein?

• A Beta-myosin heavy chain (MYH7)
• B Cardiac troponin T (TNNT2)
• C Myosin-binding protein C (MYBPC3)
• D Titin (TTN) ✓

Explanation

Titin (TTN) truncating variants are the most common identifiable genetic cause of familial dilated cardiomyopathy, accounting for approximately 20–25% of familial DCM and approximately 18% of sporadic DCM. Titin is a giant sarcomeric protein spanning from Z-disc to M-band, acting as a molecular spring regulating myocardial passive stiffness. Beta-myosin heavy chain (MYH7) and myosin-binding protein C (MYBPC3) mutations are the most common causes of hypertrophic cardiomyopathy (HCM), not DCM.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.