Any familial isolated dilated cardiomyopathy in which the cause of the disease is a mutation in the SGCD gene. The disease is Monarch Disease Ontology id MONDO_0011702 (dilated cardiomyopathy 1L). Also known as: CMD1L, SGCD familial isolated dilated cardiomyopathy, cardiomyopathy, dilated, type 1L, dilated cardiomyopathy type 1L, familial isolated dilated cardiomyopathy caused by mutation in SGCD.