APOL1 and focal segmental glomerulosclerosis: Polymorphisms in the gene for Apolipoprotein L1 (APOL1, gene name APOL1) are found only in populations of recent African ancestry and confer significant risk for chronic kidney diseases (CKD) including HIV-associated nephropathy (HIVAN), idiopathic focal segmental glomerulosclerosis (FSGS), and hypertension-attributed CKD [1–5].