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

Tyrosinemia type 2


Other Names for this Disease
  • Keratosis palmoplantaris with corneal dystrophy
  • Oculocutaneous tyrosinemia
  • Oregon type tyrosinemia
  • Richner Hanhart syndrome
  • TAT deficiency
More Names
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Overview



What is tyrosinemia type 2?

How might tyrosinemia type 2 be treated?


What is tyrosinemia type 2?

Tyrosinemia type 2 is a genetic disorder characterized by elevated blood levels of the amino acid tyrosine, a building block of most proteins. This condition is caused by a deficiency of the enzyme tyrosine aminotransferase, one of the enzymes required for the multi-step process that breaks down tyrosine. This enzyme shortage is caused by mutations in the TAT gene. This form of the disorder can affect the eyes, skin, and mental development. Symptoms often begin in early childhood and include excessive tearing, abnormal sensitivity to light (photophobia), eye pain and redness, and painful skin lesions on the palms and soles. About 50 percent of individuals with tyrosinemia type 2 have some degree of intellectual disability. This condition is inherited in an autosomal recessive manner.[1]
Last updated: 2/3/2010

How might tyrosinemia type 2 be treated?

The management of tyrosinemia type 2 revolves around dietary restriction of phenylalanine and tyrosine. This controlled diet typically lowers the blood levels of tyrosine, resulting in rapid resolution of the skin and eye symptoms. However, the effects of this controlled diet on central nervous system involvement (mental development) remains unclear. In some cases, skin lesions may be treated with oral retinoids.[2]
Last updated: 7/25/2012

References
  1. Tyrosinemia. Genetics Home Reference (GHR). 2008; http://ghr.nlm.nih.gov/condition=tyrosinemia. Accessed 2/3/2010.
  2. Wendel U. Tyrosinemia type 2. Orphanet. November 2010; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?Lng=EN&Expert=28378. Accessed 7/25/2012.