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Genetic and Rare Diseases Information Center (GARD)

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Tyrosinemia type 1

Other Names for this Disease
  • FAH deficiency
  • Fumarylacetoacetase deficiency
  • Hepatorenal tyrosinemia
  • Tyrosinemia type I
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What is tyrosinemia type 1?

How might tyrosinemia type 1 be treated?

What is tyrosinemia type 1?

Tyrosinemia type 1 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 shortage of the enzyme fumarylacetoacetate hydrolase, one of the enzymes required for the multi-step process that breaks down tyrosine. This enzyme shortage is caused by mutations in the FAH gene. Symptoms usually appear in the first few months of life and include failure to thrive, diarrhea, vomiting, jaundice, cabbage-like odor, and increased tendency to bleed (particularly nosebleeds). Tyrosinemia type I can lead to liver and kidney failure, problems affecting the nervous system, and an increased risk of liver cancer. This condition is inherited in an autosomal recessive manner.[1]
Last updated: 4/26/2010

How might tyrosinemia type 1 be treated?

There is currently no cure for tyrosinemia type 1. Individuals with this condition need to be on a special diet restricted in two amino acids, tyrosine and phenylalanine, throughout life. Affected individuals may also be treated with a medication called nitisinone. Early diagnosis and prompt treatment are essential for an improved prognosis. Some individuals require a liver transplant if their liver disease is already advanced before treatment begins.[2]

Detailed information on the treatment of tyrosinemia type 1 is available from GeneReviews.
Last updated: 4/26/2010

  1. Tyrosinemia. Genetics Home Reference (GHR). 2008; Accessed 2/3/2010.
  2. Tyrosinemia: Information for Physicians and Other Health Care Providers. Illinois Department of Public Health Web site. Accessed 4/26/2010.