A genetic metabolic disorder due to deficiency of the enzyme homogentisic acid (HGA) dioxygenase. Deficiency of this enzyme leads to the three cardinal features of alkaptonuria (the presence of homogentisic acid in the urine), ochronosis (bluish-black pigmentation in connective tissue), and arthritis. Urine that turns dark is a characteristic featu [..]

A rare inherited condition in which a person's urine turns a dark brownish-black color when exposed to air. A mutation on the HGD gene causes the condition. 13 Bio, 13 Problem; 16 Animation

A single-gene disorder identified by Archibald Garrod that is characterized by dark urine. Garrod first coined the term "inborn error in metabolism" to describe this and other congenital, in [..]

(n) a rare recessive metabolic anomaly marked by ochronosis and the presence of alkapton in the urine

A rare genetic metabolic disorder (Modern)

An inborn error of amino acid Metabolism resulting from a defect in the enzyme Homogentisate 1,2-Dioxygenase, an enzyme involved in the breakdown of Phenylalanine and Tyrosine. It is characterized by [..]

An inborn error of amino acid metabolism resulting from a defect in the enzyme homogentisate 1,2-dioxygenase and causing an accumulation of homogentisic acid in the urine. The condition is characteriz [..]

<biochemistry> An autosomal recessive condition due to the absence of homogentisic acid oxidase which produces an accumulation of homogentisic acid in the urine (causing it to darken on standing). Accumulation of homogentisic acid causes; ochronosis - a brown pigmentation of the skin and eyes, and arthritis. Origin: Gr. Ouron = urine (18 Jan [..]