holocarboxylase synthetase deficiency
Findings
No curated finding names holocarboxylase synthetase deficiency yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A rare, early-onset and life-threatening, multiple carboxylase deficiency that when left untreated, is characterized by vomiting, tachypnea, irritability, lethargy, exfoliative dermatitis, and seizures that can worsen to coma and death.
Definition from the Mondo Disease Ontology (MONDO:0009666), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Neonatal onset
HPO, annotations 2026-09-02
Features
26 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.
- 3-hydroxyisovaleric aciduriaHPOHP:0033111
- 1 of 1 reported patient
- Elevated urinary 3-methylcrotonylglycine levelHPOHP:0033596
- 1 of 1 reported patient
- Feeding difficulties in infancyHPOHP:0008872
- 1 of 1 reported patient
- HyperammonemiaHPOHP:0001987
- 1 of 1 reported patient
- Frequent (30% to 79% of cases)
- Lactic acidosisHPOHP:0003128
- 1 of 1 reported patient
- Metabolic acidosisHPOHP:0001942
- 1 of 1 reported patient
- Reduced holocarboxylase synthetase activity in cultured fibroblasts
Show the remaining 14
- Nausea and vomitingHPOHP:0002017
- Very frequent (80% to 99% of cases)
- Perioral eczemaHPOHP:0011127
- Very frequent (80% to 99% of cases)
- SeizureHPOHP:0001250
- Very frequent (80% to 99% of cases)
- Weight lossHPOHP:0001824
- Very frequent (80% to 99% of cases)
- Organic aciduriaHPOHP:0001992
- Frequent (30% to 79% of cases)
- Respiratory distressHPOHP:0002098
- 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.
- HLCSHGNC:4976
- Definitive · ClinGen · Autosomal recessive · 2021
- Definitive · Myriad Women's Health · Autosomal recessive · 2018
- Definitive · G2P · Autosomal recessive · 2017
- 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
3 names
Resolves to: holocarboxylase synthetase deficiency
- Also called
- early-onset multiple carboxylase deficiencyholocarboxylase synthase deficiencyneonatal multiple carboxylase deficiency