Severe Intellectual Disability-Progressive Postnatal Microcephaly-Midline Stereotypic Hand Movements Syndrome, also known as iqsec2-related syndromic intellectual disability, is related to severe intellectual disability-progressive postnatal microcephaly-midline stereo. An important gene associated with Severe Intellectual Disability-Progressive Postnatal Microcephaly-Midline Stereotypic Hand Movements Syndrome is IQSEC2 (IQ Motif And Sec7 Domain ArfGEF 2). Related phenotypes are seizure and hypotonia