If an enzyme were to be absent, one step in a series of biochemical reactions may not occur leading to an accumulation of an intermediate in the reaction sequence. An accumulated intermediate in a biochemical reaction may be excreted in the urine instead of the usual end product of the series of reactions. Hypotheses Alkaptonurics lack an enzyme that breaks down alkaptans to normal excretion products. Alkaptonurics inherit this inability to produce a specific enzyme. They inherit a mutant form of a gene from each of their parents and have two mutant forms of the same gene.
Some genes contain information to specify particular enzymes.
Predictions Alkaptonurics lack a specific enzyme that acts on alkaptans in a degradative manner. Parents of alkaptonurics may have a reduced amount of the same enzyme compared to indivduals from families with no incidence of alkaptonuria. This document maintained by Robert J. Huskey Last updated on August 29, 1996.