Co-occurrence of DMPK expansion and CLCN1 mutation in a patient with myotonia.
Sara LocciRosanna CardaniPaola BrunoriSabrina LucchiariGiacomo P ComiAntonio FedericoNicola De StefanoGiovanni MeolaAndrea MignarriPublished in: Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology (2021)
Only one other similar case was reported so far; however, the segregation of the two mutations and the characteristics of the muscle were not studied. Since our patient lacked the classical phenotypical and muscle histopathological characteristics of DM1 and showed mild splicing alterations despite a pathogenic DMPK expansion and the nuclear accumulation of toxic RNA, we may speculate that the co-occurrence of a CLCN1 mutation could have attenuated the severity of DM1 phenotype.