DO_rare_slim hypermethioninemia hypermethioninemia with deficiency of S-adenosylhomocysteine hydrolase GARD:13177 ORDO:88618 ICD10CM:E72.1 MIM:613752 DOID:0111039 disease_ontology A hypermethioninemia characterized by autosomal recessive inheritance of psychomotor delay, severe myopathy, hypermethioninaemia and elevated serum creatine kinase levels that has_material_basis_in compound heterozygous mutation in the AHCY gene on chromosome 20q11. hypermethioninemia due to S-adenosylhomocysteine hydrolase deficiency psychomotor retardation due to S-adenosylhomocysteine hydrolase deficiency