alkaptonuria

MONDO:0008753Mondo

Findings

No curated finding names alkaptonuria yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.

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).

Definition from the Mondo Disease Ontology (MONDO:0008753), read 2026-09-29. CC BY 4.0.

Inheritance: Autosomal recessive inheritance
Onset and course: Adult onset · Infantile onset

Features

58 features

What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.

Dark urineHPOHP:0040319
- 13 of 13 reported patients
- Frequent (30% to 79% of cases)
Elevated urinary homogentisic acidHPOHP:0033704
- 58 of 58 reported patients
- Very frequent (80% to 99% of cases)
OchronosisHPOHP:0030764
- 58 of 58 reported patients
- Very frequent (80% to 99% of cases)
Low back painHPOHP:0003419
- 33 of 35 reported patients · Adult onset
Abnormal skin pigmentationHPOHP:0001000
- Very frequent (80% to 99% of cases)

Genes

1 gene

Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.

HGDHGNC:4892
- Definitive · ClinGen · Autosomal recessive · 2020
- Definitive · Natera · Autosomal recessive · 2023
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2018
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021

Where it sits

A kind of: disorder of tyrosine metabolism

Other names

4 names

Resolves to: alkaptonuria

Also called: alcaptonuriahereditary ochronosishomogentisate 1,2-dioxygenase deficiencyhomogentisic acid oxidase deficiency

Show the remaining 46

Intervertebral disk calcificationHPOHP:0005645
- Very frequent (80% to 99% of cases)
Irregular hyperpigmentationHPOHP:0007400
- Very frequent (80% to 99% of cases)
Joint dislocationHPOHP:0001373
- Very frequent (80% to 99% of cases)
Joint stiffnessHPOHP:0001387
- Very frequent (80% to 99% of cases)
Joint swellingHPOHP:0001386
- Very frequent (80% to 99% of cases)
OsteoarthritisHPOHP:0002758
- Very frequent (80% to 99% of cases)
Abnormal heart valve morphologyHPOHP:0001654
- Frequent (30% to 79% of cases)
Abnormal nail morphologyHPOHP:0001597
- Frequent (30% to 79% of cases)
Abnormality of the noseHPOHP:0000366
- Frequent (30% to 79% of cases)
Aortic valve calcificationHPOHP:0004380
- Frequent (30% to 79% of cases)
Aortic valve stenosisHPOHP:0001650
- Frequent (30% to 79% of cases)
Back painHPOHP:0003418
- Frequent (30% to 79% of cases)
Cartilage destructionHPOHP:0100773
- Frequent (30% to 79% of cases)
Kidney stoneHPOHP:0000787
- 16 of 58 reported patients
- Frequent (30% to 79% of cases)
Mitral valve calcificationHPOHP:0004382
- Frequent (30% to 79% of cases)
Oil-drop brown pigmentation of the corneal limbusHPOHP:6000027
- Frequent (30% to 79% of cases)
Pigmentation of the scleraHPOHP:0007832
- Frequent (30% to 79% of cases)
ProstatitisHPOHP:0000024
- Frequent (30% to 79% of cases)
Tendon ruptureHPOHP:0100550
- Frequent (30% to 79% of cases)
Thickened Achilles tendonHPOHP:0004690
- 12 of 58 reported patients
- Frequent (30% to 79% of cases)
Limited hip movementHPOHP:0008800
- 33 of 58 reported patients
KyphosisHPOHP:0002808
- 31 of 58 reported patients
Dark cerumenHPOHP:6000025
- 6 of 13 reported patients
- Occasional (5% to 29% of cases)
Amyloid depositionHPOHP:0011034
- Occasional (5% to 29% of cases)
Aortic aneurysmHPOHP:0004942
- Occasional (5% to 29% of cases)
AtherosclerosisHPOHP:0002621
- Occasional (5% to 29% of cases)
Black pigment gallstonesHPOHP:0011982
- Occasional (5% to 29% of cases)
Corneal astigmatismHPOHP:0025612
- Occasional (5% to 29% of cases)
GlaucomaHPOHP:0000501
- Occasional (5% to 29% of cases)
Hemolytic anemiaHPOHP:0001878
- Occasional (5% to 29% of cases)
HypertensionHPOHP:0000822
- Occasional (5% to 29% of cases)
HypothyroidismHPOHP:0000821
- Occasional (5% to 29% of cases)
Increased susceptibility to fracturesHPOHP:0002659
- Occasional (5% to 29% of cases)
MethemoglobinemiaHPOHP:0012119
- Occasional (5% to 29% of cases)
Mitral regurgitationHPOHP:0001653
- Occasional (5% to 29% of cases)
Mitral stenosisHPOHP:0001718
- Occasional (5% to 29% of cases)
Myocardial infarctionHPOHP:0001658
- Occasional (5% to 29% of cases)
Ocular hypertensionHPOHP:0007906
- Occasional (5% to 29% of cases)
Prostatic calculusHPOHP:0034882
- Occasional (5% to 29% of cases)
Reduced bone mineral densityHPOHP:0004349
- Occasional (5% to 29% of cases)
ScoliosisHPOHP:0002650
- Occasional (5% to 29% of cases)
Limitation of knee mobilityHPOHP:0010501
- 7 of 58 reported patients
Limited shoulder movementHPOHP:0006467
- 2 of 58 reported patients
Decreased glomerular filtration rateHPOHP:0012213
- 1 of 58 reported patients
Brown pigmentation of the conjunctivaHPOHP:6000365
Diminished physical functioningHPOHP:0033666