A Novel Frameshift Mutation in Two Siblings with Merosin-deficient Congenital Muscular Dystrophy

Abstract

We present two siblings with elevated serum creatine kinaseconcentrations, developmental delay, muscle weakness, andcontractures of the lower limbs. Cranial magnetic resonanceimaging revealed diffuse white matter hyperintensity in bothsiblings. In the older sister, muscle biopsy was performed;immunohistochemical studies showed a dystrophic patternand merosin deficiency. With the diagnosis of merosin-deficientcongenital muscular dystrophy (MDC1A), LAMA2 genemutation analysis revealed an NM_000426.3:c.163_163delA;(p.N55Mfs*16) homozygous frameshift mutation in the siblings.This mutation leads to a premature stop codon and has not beenreported previously in the literature.