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Synonyms: Hereditary ochronosis | Homogentisic acid oxidase deficiency

A rare disorder of phenylalanine and tyrosine metabolism characterized by the accumulation of homogentisic acid (HGA) and its oxidized product benzoquinone acetic acid (BQA) in various tissues (e.g. cartilage connective tissue) and body fluids (urine sweat) causing urine to darken when exposed to air as well as grey-blue coloration of the sclera and ear helix (ochronosis) and a disabling joint disease involving both the axial and peripheral joints (ochronotic arthropathy).

Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview.

Reference: Access aggregated data from Orphanet at Orphadata.

Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http: // Data version September 2023.

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Advocacy Organizations

Mississippi Metabolics Foundation

Mississippi Metabolics Foundation (MMF) was founded to raise awareness, educate, and provide support to those living or caring for someone with genetic metabolic disorders/inborn errors of metabolism (IEM).

Clinical Trials

For a list of clinical trials in this disease area, please click here.