Besides, several cases of TWNK mutations in an autosomal recessive inherited trait can cause infantile onset spinocerebellar ataxia (IOSCA) (OMIM #271245) with the main clinical features including muscle hypotonia, athetosis, ataxiaophthalmoplegia, hearing deficit, sensoryaxonal neuropathy, female hypogonadism and epilepticencephalopathy [18] and Perrault syndrome 5 (PRLTS5, OMIM #616138) with hearing loss, female hypergonadotropic hypogonadism and ataxia [17]. The gene discussed is TWNK; the disease is mitochondrial DNA depletion syndrome 7 (hepatocerebral type).