Danon Disease: Clinical Manifestations, Pathophysiology, and Treatment

Area of Science:

• Genetics
• Cardiology
• Cell Biology

Background:

• Danon disease is a rare X-linked dominant vacuolar myopathy.
• It stems from mutations in the lysosome-associated membrane protein-2 (LAMP-2) gene, particularly the LAMP-2B subtype.
• LAMP-2 is crucial for macroautophagy, and its dysfunction impairs cellular component degradation.

Purpose of the Study:

• To describe the pathophysiology and clinical manifestations of Danon disease.
• To highlight characteristic diagnostic findings.
• To review current and emerging treatment strategies.

Main Methods:

• Review of existing literature on Danon disease.
• Analysis of clinical data and diagnostic imaging.
• Overview of ongoing gene therapy clinical trials.

Main Results:

• Danon disease presents with a triad of intellectual disability, cardiomyopathy, and skeletal myopathy in males, and primarily cardiomyopathy in females.
• Characteristic findings include autophagic vacuoles with unique sacrolemmal features, specific ECG abnormalities, and cardiac MRI patterns.
• Cardiomyopathy can be hypertrophic or dilated, with arrhythmias being common.

Conclusions:

• Danon disease is a severe, often fatal, cardiac condition requiring timely diagnosis and management.
• Heart transplantation is a current treatment, while gene therapy offers a potential future therapeutic avenue.
• RP-A501, a gene therapy agent, is in Phase II trials for delivering LAMP-2 to cardiomyocytes.