Contributor: Gordon K. Klintworth
Alport syndrome is an inherited progressive glomerulonephritis with hematuria typified by an abnormal basement membrane of the glomeruli. It is caused by mutations in genes that encode for collagen type IV (COL4A3, COL4A4, COL4A5, and COL4A6). The prevalence of this syndrome is 1 in 5,000.  Based on the mode of  inheritance Alport syndrome is subdivided into X-linked recessive Alport syndrome [Alport syndrome - X-linked recessive], autosomal recessive Alport syndrome [Alport syndrome - autosomal recessive], and autosomal dominant Alport syndrome [Alport syndrome - autosomal dominant]. Genes for Alport have been mapped to the X-chromosome (COL4A5, COL4A6) and chromosome 2 (COL4A3, COL4A4).