Notably, several transporters for these ions are upregulated in CPTs, including SLC4A7, SLC4A8, and SLC8A1. Both CPP and CPC are often accompanied by hydrocephalus (Konar et al, 2021), presumably through some combination of CSF overproduction, physical blockage of drainage routes by the tumor mass, and CSF malabsorption. The gene discussed is SLC4A8; the disease is neoplasm.