The gene coding for the α5 chain of type IV collagen (α5(IV) collagen), which maps to Xq22, is a candidate gene for the X-linked dominant disease Alport syndrome (AS). Using three cDNA clones, covering the 3′ end of the α5(IV) collagen gene, 3 of 38 patients have been identified with mutations in this gene. Each of these patients shows a gross rearrangement of DNA: a deletion of at least 35 kb, an insertion/deletion event involving approximately 25 kb, and a duplication of at least 35 kb of DNA
