Tyrosinemia, Type III (TYR III)



Tyrosinemia, type III (TYR III) is an inherited condition in which the body is unable to break down certain building blocks of proteins, known as amino acids. People with tyrosinemia, type III are unable to break down an amino acid known as tyrosine. This condition can result in learning problems, seizures, and loss of balance if untreated. There are three types of tyrosinemia (I, II, and III); TYR III is the least common type, with fewer than 20 reported cases. Signs of TYR III are highly variable and not well known and may include poor coordination and balance or seizures. These signs may occur when a baby eats foods that the body cannot break down. 

Condition Type:



Tyrosinemia, type III (TYR III) is a very rare condition. Only a few cases have ever been reported.

More Information for Parents:
Also known as:
  • Tyrosinemia due to 4-hydroxyphenylpyruvate dioxygenase deficiency
  • Tyrosinemia due to 4-hydroxyphenylpyruvic acid oxidase deficiency
  • Tyrosinemia due to HPD deficiency
  • Tyrosinemia type III

Core Conditions