PIGA and Hypsarrhythmia: In addition to early onset infantile spasms with hypsarrhythmia on EEG, IDD and profound developmental delay, the patients with more severe manifestations of PIGA germline mutations (patients: IV-2, IV-4 [15], III-1 [17], III-9 [16], 1, 2, and 5 [18], and our case [this report]) also present with dysmorphic facial features, multiple CNS abnormalities, such as thin corpus callosum and delayed myelination, as well as hypotonia (Table 1).