Monarch Disease Ontology id MONDO_0010258 (MEHMO syndrome) is characterized by severe intellectual deficit, epilepsy, microcephaly, hypogenitalism, and obesity. Growth delay and diabetes are also present. To date, it has been described in seven boys, all of whom died within the first two years of life. The causative gene has been localized to the 21.1-22.13p region of the X chromosome and the syndrome appears to result from mitochondrial dysfunction. Also known as: MEHMO, MEHMO syndrome, X-linked recessive, MRXS20, MRXS25, MRXSBRK, X-linked intellectual disability-epileptic seizures-hypogenitalism-microcephaly-obesity syndrome, intellectual disability, X-linked, syndromic 20, intellectual disability, X-linked, syndromic 25.