has material basis in autosomal recessive disease developmental and epileptic encephalopathy 12 disease_ontology MIM:613722 DEE12 DOID:0080459 A developmental and epileptic encephalopathy characterized by onset of refractory seizures in the first year of life with normal to mild developmental delay before onset of seizures but developmental regression and stagnation after seizure onset that has_material_basis_in homozygous or compound heterozygous mutation in the PLCB1 gene on chromosome 20p12.3. early infantile epileptic encephalopathy 12 developmental and epileptic encephalopathy autosomal recessive inheritance