Alkaptonuria

Alkaptonuria (AKU) is a rare autosomal recessive genetic disorder caused by a deficiency of the enzyme homogentisate 1,2 dioxygenase (HGD), leading to the accumulation of homogentisic acid (HGA) in the body. This excess HGA oxidizes into an ochronotic pigment polymer, causing a condition called ochronosis. Alkaptonuria follows Mendelian recessive inheritance and was first described in 1908 by Archibald Garrod. The disease is rare worldwide, with a prevalence of 1 per 100,000 to 250,000 globally and 1 case per million in the United States. It is more common in the Dominican Republic and Slovakia, with a slightly higher occurrence in the African population. Both men and women are affected, but the disease severity is higher in men.