The hydrocephalus prevalence was 0.50% in APOL1-G0/G0 individuals (serving as reference), 0.65% in APOL1-G0/G1 individuals (odds ratio 1.31 [0.99–1.74], P=0.057), and 0.90% in APOL1-G1/G1 individuals (odds ratio 1.85 [1.16–2.86], P=0.0092) (Supplementary Figure S5A). This evidence concerns the gene APOL1 and Hydrocephalus.