___ is caused by a defect in the synthesis of the α-3, α-4, or α-5 chains of type IV collagen, which is a constituent of the glomerular basement membrane (GBM). Most cases of ___ are X-linked mutations in the COL4A5 gene, but autosomal recessive or dominant mutations in COL4A3 and COL4A4 account for a sizable minority of cases. ____ may also present with sensorineural deafness and anterior lenticonus.
