Cardiac pathology exceeds skeletal muscle pathology in two cases of limb-girdle muscular dystrophy type 2I

Limb-girdle muscular dystrophy type 2I (LGMD-2I) is caused by mutations in the fukutin-related protein gene (FKRP) that lead to abnormal glycosylation of α-dystroglycan in skeletal muscle. Heart involvement in LGMD-2I is common, but little is known about a underlying cardiac pathology. Herein we describe two patients with LGMD-2I (homozygous FKRP mutation c.826C>A, p.Leu276Ile) who developed severe congestive heart failure that required cardiac transplantation. The dystrophic pathology and impairment of α-dystroglycan glycosylation were severe in the heart but mild in skeletal muscle, underscoring the lack of correlation between cardiac and skeletal muscle involvement in some LGMD-2I patients.