Primary coenzyme Q10 deficiency-7: expanded phenotypic spectrum and a founder mutation in southern Chinese.

Primary coenzyme Q10 deficiency-7 (COQ10D7) is a rare mitochondrial disease caused by biallelic mutations in . Here we report the largest cohort of COQ10D7 to date, with 11 southern Chinese patients confirmed with biallelic mutations. Five of them have the classical neonatal-onset encephalo-cardiomyopathy, while the others have infantile onset with more heterogeneous clinical presentations. We also identify a founder mutation (NM_016035.5): c.370G>A, p.(Gly124Ser) for COQ10D7, suggesting a higher chance of occurrence in the southern Chinese. This study helps improve understanding of the clinical spectrum of this disorder.