Milder phenotype of congenital muscular dystrophy in a novel POMT1 mutation

Congenital muscular dystrophies (CMD) with hypoglycosylated α-dystroglycan due to POMT1 mutations are associated with clinical phenotypes that vary in severity.

We describe a patient with congenital hypotonia, generalized weakness, elevated creatine kinase (CK), and normal brain imaging.

Histochemical analysis of the index case's muscle showed deficiency of glycosylated α-dystroglycan and secondary merosin deficiency. Genetic testing revealed a novel mutation in exon 20 of the POMT1 gene.

Our patient's milder form of CMD adds to the emerging evidence of an expanding phenotype caused by POMT1 mutations. The histopathological findings of the muscle biopsy in this case support the need for careful clinical, genetic, and histochemical diagnostic interpretation.