ATIC gene mutations have been associated with AICAR transformylase/IMP cyclohydrolase deficiency (OMIM # 608688) manifesting with severe neurodevelopmental disorder (comprising intellectual disability, hypotonia, and seizures), dysmorphic features, and congenital blindness, due to optical atrophy, but this phenotype is only based on a single case [54]. The gene discussed is ATIC; the disease is hyperinsulinemic hypoglycemia, familial, 4.