COL4A2 and COL4A1/A2-related disorder: Pathogenic variants in type IV collagens cause Alport syndrome (COL4A3, COL4A4, and COL4A5), which primarily affects the glomerular basement membrane (11, 12) and Gould syndrome (COL4A1 and COL4A2), a congenital multisystem disorder that includes highly variable cerebrovascular disease, pediatric epilepsy, ocular anterior segment dysgenesis, skeletal myopathy, and nephropathy (13, 14, 15, 16, 17, 18).