For example, prenatal cerebellar development is linked to homeobox genes like PAX-2 and signaling genes like Fibroblast Growth Factor 8,41,64,65 which are associated with early kidney development and CKD causes such as nephron development disorders, kidney agenesis, and vesicoureteral reflux.66,67,68,69,70,71 It is conceivable that the observed cerebellar features indicate a predisposition to lower GM, with declining kidney function in pediatric CKD acting as a second hit that worsens this decline with age. The gene discussed is PAX2; the disease is vesicoureteral reflux.