COQ6 and coenzyme Q10 deficiency: A mutation of the COQ6 gene was first reported as a cause of primary CoQ10 deficiency in the study of Heeringa et al. (2011) The authors reported that all affected patients (n = 11) presenting with SRNS and SNHL showed proteinuria with a median onset age of 1.2 years (range, 0.2–6.4 years) and ESRD with a median onset age of 1.7 years (range, 0.4–9.3 years); five cases also presented with extrarenal involvement such as white matter abnormalities, seizures, ataxia, and facial dysmorphism.