What happens because of the HGD gene change?
Changes in the HGD gene cause a person's body to be deficient of the homogentisate 1,2-dioxygenase enzyme. When a person does not have this enzyme, homogentisic acid cannot be broken down into maleyloacetoacetic acid in the tyrosine degradation pathway. When homogentisic acid cannot be broken down, it accumulates in the body.
ntrone WJ, Perry MB, Troendle J, Tsilou E, Kayser MA, Suwannarat P, O'Brien KE, Bryant J, Sachdev V, Reynolds JC, Moylan E, Bernardini I, Gahl WA. A 3-year randomized therapeutic trial of nitisinone in alkaptonuria. Mol Genet Metab. 2011;103:307?14.