This category includes patients with mutations in the aprataxin (APTX) gene, causing ataxia and oculomotor apraxia, with mutations in the electron-transferring flavoprotein dehydrogenase gene (ETFDH), causing isolated myopathy, and with mutations in Serine/threonine-protein kinase B-raf (BRAF), causing cardiofaciocutaneous (CFC) syndrome [6]. The gene discussed is ETFDH; the disease is myopathy.