PNPO deficiency, due to its gene mutations, has been widely studied in infantile and neonatal epileptic encephalopathy (Mills et al., 2005; Hoffmann et al., 2007; Hatch et al., 2016; di Salvo et al., 2017; Ciapaite et al., 2020). The gene discussed is PNPO; the disease is Epileptic encephalopathy.