Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.

Diseases

Genetic and Rare Diseases Information Center (GARD)

Print friendly version

Alport syndrome


Other Names for this Disease

  • Alport syndrome, X-linked
  • Congenital hereditary hematuria
  • Hemorrhagic familial nephritis
  • Hemorrhagic hereditary nephritis
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Inheritance

Newline Maker

How is Alport syndrome inherited?

Alport syndrome can have different inheritance patterns. About 80 percent of cases are caused by mutations in the COL4A5 gene and are inherited in an X-linked recessive pattern. This gene is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the COL4A5 gene in each cell is sufficient to cause kidney failure and other severe symptoms of the disorder. In females (who have two X chromosomes), a mutation in only one copy of the COL4A5 gene usually only results in hematuria, but some women experience more severe symptoms. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.[1]

In approximately 15 percent of cases, Alport syndrome results from mutations in both copies of the COL4A3 or COL4A4 gene and is inherited in an autosomal recessive pattern. The parents of an individual with the autosomal recessive form of this condition each have one copy of the mutated gene and are called carriers. Some carriers are unaffected and others develop a less severe condition called thin basement membrane nephropathy, which is characterized by hematuria.[1]

Alport syndrome has an autosomal dominant pattern of inheritance in about 5 percent of cases. People with this form of Alport syndrome have one mutation in either the COL4A3 or COL4A4 gene in each cell. It remains unclear why some individuals with one mutation in the COL4A3 or COL4A4 gene have autosomal dominant Alport syndrome and others have thin basement membrane nephropathy.[1]

Last updated: 8/1/2013

References
  1. Alport syndrome. Genetics Home Reference. April 2009; http://ghr.nlm.nih.gov/condition/alport-syndrome. Accessed 10/24/2011.


Other Names for this Disease
  • Alport syndrome, X-linked
  • Congenital hereditary hematuria
  • Hemorrhagic familial nephritis
  • Hemorrhagic hereditary nephritis
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.