Congenital Muscular Dystrophy with Secondary Merosin Deficiency and Normal Brain MRI: A Novel Entity?

We describe two Scottish siblings affected by a form of congenital muscular dystrophy characterised by a severe clinical phenotype, similar to that observed in the 6q-linked merosin-deficient CMD but in whom brain MRI and cognitive development were normal. The maximal function achieved in the 2 siblings was sitting independently. Serum CK were grossly elevated and the skin and muscle biopsies showed a severe reduction of merosin in both. The normal brain MRI and normal cognitive development distinguish this form from Fukuyama congenital muscular dystrophy, muscle-eye-brain disease or other forms of CMD with secondary partial merosin deficiency and abnormal brain MRI and/or mental retardation. Linkage analysis excluded all the known loci for CMD. We propose that this may represent a novel variant of CMD.

Key words

Congenital muscular dystrophy - Merosin - Laminin α2 - Fukuyama CMD

References

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