has material basis in germline mutation in EHMT1 congenital nervous system disorder Kleefstra syndrome autosomal dominant non-syndromic intellectual disability Kleefstra syndrome 1 https://github.com/monarch-initiative/mondo/issues/10711 GARD:0025497 A Kleefstra syndrome that is characterized by severe intellectual disability, hypotonia, microcephaly, epileptic seizures, flat face with hypertelorism, synophrys, anteverted nares, everted lower lip, carp mouth with macroglossia, and heart defects, and that has material basis in a microdeletion in the chromosome region 9q34.3 or a mutation in the EHMT1 gene located in that region. KLEFS1 UMLS:C0795833 SCTID:724207001 Kleefstra syndrome 1 MONDO:0027407 chromosome 9q34.3 deletion syndrome MESH:C563043 OMIM:610253 DOID:0060352 9q-syndrome EHMT1-related Kleefstra syndrome DOID:0070075 NCIT:C129976 MEDGEN:208639 intellectual disability, autosomal dominant