Developmental and Epileptic Encephalopathy due to Biallelic Pathogenic Variants in PIGM.

Our findings establish PIGM as a causative gene of early-onset developmental and epileptic encephalopathy and expand the clinical and radiological spectrum of PIGM deficiency to include hypomyelination and prenatal onset. This study underscores the importance of including PIGM in the differential diagnosis of developmental and epileptic encephalopathy and leukoencephalopathies and provides further insight into the molecular mechanisms underlying phenotypic variability of GPI-anchor disorders.