What dietary substance is primarily implicated in alkaptonuria?

Alkaptonuria is a rare metabolic disorder that results from a deficiency of the enzyme homogentisate oxidase, which is involved in the catabolism of the amino acid tyrosine. Individuals with alkaptonuria are unable to properly break down homogentisic acid, a byproduct of tyrosine and phenylalanine metabolism. As a result, homogentisic acid accumulates in the body and can be excreted in the urine, leading to its dark coloration upon exposure to air.

Since the condition is directly related to an issue with metabolizing tyrosine, this dietary substance is primarily implicated in alkaptonuria. The buildup of homogentisic acid can also lead to various complications over time, including joint problems and tissue damage due to the deposition of the pigment in connective tissues. Thus, understanding the role of tyrosine in this metabolic pathway is key to grasping the underlying causes of alkaptonuria.