COL4A4 and chronic kidney disease: Functional studies are needed to confirm the biological role of COL4A4 in CKD and ESKD. In contrast, rs150979437 was carried by 2 healthy individuals, 9 CKD patients, and 16 ESKD patients, potentially implicating a stronger genetic effect on kidney disease progression. Furthermore, Gbadegesin et al. demonstrated an association between APOL1 G1 and G2 variants and increased CKD risk among West Africans [7].