Exclusive paternal expression and novel alternatively spliced variants of ε-sarcoglycan mRNA in mouse brain

Mutations of SGCE encoding ε-sarcoglycan cause myoclonus-dystonia. SGCE is paternally expressed; however, 5–10% of patients show maternal inheritance of the disease. We found Sgce was exclusively paternally expressed in mice by using a novel polymorphism marker. The result was confirmed in Sgce heterozygous knockout mice. This finding suggests that maternally inherited myoclonus-dystonia may not result from maternal expression of SGCE. Furthermore, we report a new family of alternatively spliced Sgce mRNA expressed in the brain coding for different C-terminal sequences possessing a PDZ-binding motif. Our results provide a better basis for diagnosis and understanding of the pathogenesis of myoclonus-dystonia.