To determine whether pathologically increased Wnt and Notch pathway signaling in SIOD begins prenatally, we performed indirect immunofluorescence for unphosphorylated β-catenin and NICD in a 15-week-gestation SMARCAL1-deficient kidney and age-matched unaffected kidneys. The gene discussed is NOTCH1; the disease is Schimke immuno-osseous dysplasia.