Human Phenotype Ontology 
Grandparent Node:
Abnormality of the skin (HP:0000951)help
Parent Node:
Abnormality of skin morphology (HP:0011121)help
..Starting node
Ochronosis (HP:0030764)help
Term ID: 30764
Name: Ochronosis
Definition: Brown or blue-gray discoloration of the skin that can present on the axillary and inguinal areas, face, palms or soles. In addition, blue-black discoloration can be apparent on skin overlying cartilage in which the pigment is deposited, such as the ears. This is a characteristic manifestation of alkaptonuria, which is an autosomal recessively inherited deficiency of homogentisic acid oxidase that results in accumulation of homogentisic acid in collagenous structures. The sclerae are also typically involved.
Reference: HP:0030764
Genes and Diseases:
       Child Nodes:

 Sister Nodes: 
..expandAbnormal blistering of the skin (HP:0008066) help
..expandAbnormal cutaneous collagen fibril morphology (HP:0031512) help
..expandAbnormal cutaneous elastic fiber morphology (HP:0025082) help
..expandAbnormal dermoepidermal junction morphology (HP:0031538) help
..expandAbnormal elasticity of skin (HP:0010647) help
..expandAbnormal epidermal morphology (HP:0011124) help
..expandAbnormality of skin pigmentation (HP:0001000) help
..expandDermal translucency (HP:0010648) help
..expandDry skin (HP:0000958) help
..expandElevated dermal desmosine content (HP:0025083) help
..expandGeneralized abnormality of skin (HP:0011354) help
..expandLichenification (HP:0100725) help
..expandLocalized skin lesion (HP:0011355) help
..expandPallor (HP:0000980) help
..expandPoikiloderma (HP:0001029) help
..expandRegional abnormality of skin (HP:0011356) help
..expandStiff skin (HP:0030053) help
..expandThickened skin (HP:0001072) help
InputHPO IDHPO termDistanceGeneGene id entrezHGNC IDDiseaseIdDiseaseNameFrequencyOnsetHGMD variantsClinVar variants
HPO disease - gene - phenotype typical associations:
HPO disease - gene - phenotype less frequent non-typical associations:
HP:0030764HP:0030764Ochronosis0HGD CL E G H30814892OMIM:203500Alkaptonuria77

Genes (1) :HGD

Diseases (1) :OMIM:203500

Human Phenotype Ontology(HPO) is developed by the Human Phenotype Ontology Consortium. The version used here is December 15 2022 release.