Succinyl-CoA synthetase (SUCLA2) deficiency in two siblings with impaired activity of other mitochondrial oxidative enzymes in skeletal muscle without mitochondrial DNA depletion.
Mitochondrial DNA depletion syndrome (MDS) is characterized by a reduction in mtDNA copy number and has been associated with mutations in eight nuclear genes, including enzymes involved in mitochondrial nucleotide metabolism (POLG, TK2, DGUOK, SUCLA2, SUCLG1, PEO1) and MPV17.
One pedigree with four patients has been recently described with mitochondrial DNA depletion and mutation in SUCLA2 gene leading to succinyl-CoA synthase deficiency.