microcephaly—seizures—and developmental delay
Definition An autosomal recessive neurodevelopmental disorder (OMIM:613402) characterised by infant onset of seizures, progressive primary microcephaly*, severe intellectual disability, delayed motor milestones, minimal to absent speech, often accompanied by behavioural problems with hyperactivity. Some cases are associated with cerebellar atrophy and peripheral neuropathy
*Without neuronal migration or structural defects.
Molecular pathology Defects of PNKP, which encodes polynucleotide kinase 3′-phosphatase, an enzyme that plays a key role in repair of DNA damage, cause microcephaly—seizures—and developmental delay.
Synonyms Epileptic encephalopathy—early infantile—10, MCSZ,