Merosin-deficient congenital muscular dystrophy with mental retardation and cerebellar cysts unlinked to the LAMA2, FCMD and MEB loci

We report a case of congenital muscular dystrophy with secondary merosin de ficiency, structural involvement of the central nervous system and mental r etardation in an 8-year-old girl from a consanguineous family. She had earl y-onset hypotonia, generalized muscle wasting, with weakness especially of the neck muscles, joint contractures, mental retardation and high creatine kinase. Muscle biopsy showed dystrophic changes with partial deficiency of the laminin alpha (2) chain. Cranial magnetic resonance imaging revealed mu ltiple small cysts in the cerebellum, without cerebral cortical dysplasia o r white matter changes. The laminin alpha (2) chain (6q2), Fukuyama type co ngenital muscular dystrophy (9q31-q33) and muscle-eye-brain disease (1p32-p 34) loci were all excluded by linkage analysis. We suggest that this case r epresents a new entity in the nosology of congenital muscular dystrophy. (C ) 2000 Elsevier Science B.V. All rights reserved.