What gene change causes Alkaptonuria?
Changes in the HGD gene cause Alkaptonuria. This gene provides instructions for making the enzyme homogentisate 1,2-dioxygenase that breaks down homogentisic acid. This is the only gene that is known to cause Alkaptonuria. At least 115 different changes that cause Alkaptonuria have been identified in the HGD gene. A database of these changes can be found at http://hgddatabase.cvtisr.sk/variants.php?action=search_unique&select_db=HGD.
More Causes Content
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.
Does anything make Alkaptonuria worse?
There is nothing that can cause someone's Alkaptonuria to worsen. However, the buildup of homogentisic acid affects connective tissue that leads to arthritis. To try and reduce the progression of severe arthritis, physical stress to the spine and large joints should be avoided.