has material basis in germline mutation in HGD skin disorder alkaptonuria https://github.com/monarch-initiative/mondo/issues/4985 https://github.com/monarch-initiative/mondo/issues/5682 https://rarediseases.info.nih.gov/diseases/5775/alkaptonuria https://www.malacards.org/card/alkaptonuria ICD9:270.2 homogentisate 1,2-dioxygenase deficiency NCIT:C84546 homogentisic acidura aku alcaptonuria ochronosis, hereditary NORD:750 GARD:0005775 hereditary ochronosis MESH:D000474 homogentisic acid oxidase deficiency Orphanet:56 SCTID:360378009 NANDO:2200504 MEDGEN:1413 icd11.foundation:1761652827 A metabolic disease 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). DOID:9270 MONDO:0008753 UMLS:C0002066 MedDRA:10001689 alkaptonuria OMIM:203500 alkaptonuric ochronosis disorder of tyrosine metabolism obsolete pigmented conjunctival lesion