Clinical and genetic aspects of defects in the mitochondrial iron–sulfur cluster synthesis pathway

Iron–sulfur clusters are evolutionarily conserved biological structures which play an important role as cofactor for multiple enzymes in eukaryotic cells. The biosynthesis pathways of the iron–sulfur clusters are located in the mitochondria and in the cytosol. The mitochondrial iron–sulfur cluster biosynthesis pathway (ISC) can be divided into at least twenty enzymatic steps. Since the description of frataxin deficiency as the cause of Friedreich’s ataxia, multiple other deficiencies in ISC biosynthesis pathway have been reported. In this paper, an overview is given of the clinical, biochemical and genetic aspects reported in humans affected by a defect in iron–sulfur cluster biosynthesis.