What disease is associated with a disorder of tyrosine catabolism?

What disease is associated with a disorder of tyrosine catabolism?

• A. Phenylketonuria
• B. Homocystinuria
• C. Tyrosinemia
• D. Maple syrup urine disease

Answer: (C)

Tyrosinemia is specifically associated with a disorder in the catabolism of tyrosine, an amino acid. In individuals with this condition, there are genetic defects related to the enzymes involved in the breakdown pathway of tyrosine. The most commonly recognized forms are tyrosinemia type I, which results from a deficiency of the enzyme fumarylacetoacetate hydrolase, and type II, caused by a deficiency in tyrosine aminotransferase. These enzyme deficiencies lead to the accumulation of toxic metabolites, causing a variety of health issues, including liver and kidney damage as well as neurological problems.

The metabolic pathway of tyrosine is essential both for generating energy and for producing important neurotransmitters. Disturbances in this pathway can lead to severe complications, which is why tyrosinemia is clinically significant. Other conditions listed, such as phenylketonuria, homocystinuria, and maple syrup urine disease, involve different metabolic pathways and disorders, primarily related to the metabolism of phenylalanine, methionine, and branched-chain amino acids respectively, rather than tyrosine itself. This specificity of tyrosinemia distinctly characterizes its association with tyrosine catabolism disorders.