Tyrosinemia is metabolic disorder caused by a genetically linked deficiency in one of 3 enzymes. The enzymes are needed to properly breakdown an amino acid call tyrosine, which can become toxic if it builds up in the liver, kidneys or central nervous system.

Tyrosinemia I is the most common of the three types and affects about 1 in 100,000 people worldwide. In the U.S., an estimated 1 in 100 to 150 people are carriers. The disease is more common in Norway and Finland, where it affects 1 in 60,000 births, and in Quebec, Canada, where it affects 1 in 16,000 people. In the Saguenay-Lac-Saint-Jean region of Quebec, the disease affects 1 in 1,846 people. Tyrosinemia Type 1 is now included in the Ashekanazi Jewish Screening Panel at the Icahn School of Medicine at Mount Sinai.

For more information and resources, visit the National Institutes of Health (NIH) Genetics Home Reference and the National Organization for Rare Disorders (NORD).