galactokinase deficiency
Findings
No curated finding names galactokinase deficiency yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Galactokinase deficiency is a rare mild form of galactosemia characterized by early onset of cataract and an absence of the usual signs of classic galactosemia, i.e. feeding difficulties, poor weight gain and growth, lethargy, and jaundice.
Definition from the Mondo Disease Ontology (MONDO:0009255), read 2026-09-29. CC BY 4.0.
Features
27 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.
- Reduced erythrocyte galactokinase activityHPOHP:6000723
- 2 of 2 reported patients
- Abnormal circulating enzyme concentration or activityHPOHP:0012379
- Very frequent (80% to 99% of cases)
- Elevated circulating galactitol concentrationHPOHP:0410061
- Very frequent (80% to 99% of cases)
- HypergalactosemiaHPOHP:0012024
- Very frequent (80% to 99% of cases)
- Increased level of galactitol in urineHPOHP:0410062
- Very frequent (80% to 99% of cases)
- CataractHPOHP:0000518
- Frequent (30% to 79% of cases)
- Nuclear cataractHPOHP:0100018
- Frequent (30% to 79% of cases)
- HepatomegalyHPOHP:0002240
- Occasional (5% to 29% of cases)
- HepatosplenomegalyHPOHP:0001433
- Occasional (5% to 29% of cases)
- Hypergonadotropic hypogonadismHPOHP:0000815
- Occasional (5% to 29% of cases)
- HyperinsulinemiaHPOHP:0000842
- Occasional (5% to 29% of cases)
- Intellectual disabilityHPOHP:0001249
- Occasional (5% to 29% of cases)
Show the remaining 15
- Motor delayHPOHP:0001270
- Occasional (5% to 29% of cases)
- Premature ovarian insufficiencyHPOHP:0008209
- Occasional (5% to 29% of cases)
- Small for gestational ageHPOHP:0001518
- Occasional (5% to 29% of cases)
- Speech apraxiaHPOHP:0011098
- Occasional (5% to 29% of cases)
- Failure to thriveHPOHP:0001508
- Very rare (1% to 4% of cases)
- Feeding difficultiesHPOHP:0011968
- Very rare (1% to 4% 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.
- GALK1HGNC:4118
- Definitive · ClinGen · Autosomal recessive · 2021
- Definitive · Myriad Women's Health · Autosomal recessive · 2018
- Definitive · G2P · Autosomal recessive · 2015
- Definitive · Natera · Autosomal recessive · 2023
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2020
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
5 names
Resolves to: galactokinase deficiency
- Also called
- galactokinase deficiency galactosemiagalactokinase deficiency with cataractsgalactosemia type 2GALK deficiencyGALK-D