NPHP1 and normal pressure hydrocephalus: To date, mutations in more than 20 different genes have been identified to cause NPH (Braun and Hildebrandt, 2017; Devlin and Sayer, 2019; Petzold et al., 2023), the major ones being NPHP1 and NPHP4 genes, which account for 53% and 5% of cases, respectively (Petzold et al., 2023).