Despite previous observations that CHCHD10 encodes a protein largely localized to the intermembrane space of mitochondria in the MICOS complex14 and evidence that the S59L mutation reduces mitochondrial length and disorganizes mitochondrial cristae morphology13, neither the normal function of endogenous CHCHD10 nor the nature of the FTD/ALS-associated CHCHD10 mutations have been investigated. This evidence concerns the gene CHCHD10 and amyotrophic lateral sclerosis.