The BAG3-Pro209Leu mutation is associated with early onset MFM and severe restrictive cardiomyopathy (RCM), often necessitating heart transplantation during childhood.
Genetic testing demonstrated heterozygous mutation Pro209Leu (c.626C > T) in exon 3 of BAG3 gene causing severe myopathy and neuropathy, often associated with restrictive cardiomyopathy.