[Molecular genetics of Alport syndrome].

Alport syndrome is a hereditary glomerulonephritis in which progressive loss of kidney function is often accompanied by sensorineural deafness. Ultrastructural studies in glomerular basement membranes (GBM) of Alport syndrome patients implicate an altered GBM protein structure as the cause of nephritis. The product of COL4A5, the alpha 5 (IV) collagen chain, is a specific component of GBM of the kidney. Various mutations in the COL4A5 gene have been identified in X-linked dominant Alport syndrome, and these aberrations of the alpha 5 (IV) can account for at least a part of X-linked Alport syndrome.