homocystinuria due to methylene tetrahydrofolate reductase deficiency
Findings
No curated finding names homocystinuria due to methylene tetrahydrofolate reductase deficiency yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Homocystinuria due to methylene tetrahydrofolate reductase (MTHFR) deficiency is a metabolic disorder characterized by neurological manifestations.
Definition from the Mondo Disease Ontology (MONDO:0009353), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
HPO, annotations 2026-09-02
Features
50 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.
- Abnormal circulating enzyme concentration or activityHPOHP:0012379
- Very frequent (80% to 99% of cases)
- Atypical behaviorHPOHP:0000708
- Very frequent (80% to 99% of cases)
- CystathioninemiaHPOHP:0003286
- Very frequent (80% to 99% of cases)
- Gait disturbanceHPOHP:0001288
- Very frequent (80% to 99% of cases)
- HomocystinuriaHPOHP:0002156
- Very frequent (80% to 99% of cases)
- HyperhomocystinemiaHPOHP:0002160
- Very frequent (80% to 99% of cases)
Show the remaining 38
- Brain imaging abnormalityHPOHP:0410263
- Frequent (30% to 79% of cases)
- HypomethioninemiaHPOHP:0003658
- Frequent (30% to 79% of cases)
- Mental deteriorationHPOHP:0001268
- Frequent (30% to 79% of cases)
- Peripheral neuropathyHPOHP:0009830
- Frequent (30% to 79% of cases)
- Psychotic episodesHPOHP:0000725
- Frequent (30% to 79% of cases)
- SeizureHPOHP:0001250
- Frequent (30% to 79% 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.
- MTHFRHGNC:7436
- Definitive · ClinGen · Autosomal recessive · 2019
- Definitive · G2P · Autosomal recessive · 2016
- Definitive · Natera · Autosomal recessive · 2023
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2023
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
2 names
Resolves to: homocystinuria due to methylene tetrahydrofolate reductase deficiency
- Also called
- methylene tetrahydrofolate reductase deficiencyMTHFR deficiency