congenital bile acid synthesis defect 2
Findings
No curated finding names congenital bile acid synthesis defect 2 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Congenital bile acid synthesis defect type 2 (BAS defect type 2) is an anomaly of bile acid synthesis characterized by severe and rapidly progressive cholestatic liver disease, and malabsorption of fat and fat-soluble vitamins.
Definition from the Mondo Disease Ontology (MONDO:0009339), 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.
- Abnormal circulating enzyme concentration or activityHPOHP:0012379
- Very frequent (80% to 99% of cases)
- Giant cell hepatitisHPOHP:0200084
- Very frequent (80% to 99% of cases)
- HyperbilirubinemiaHPOHP:0002904
- Very frequent (80% to 99% of cases)
- Abnormal serum bile acid concentrationHPOHP:0030984
- Frequent (30% to 79% of cases)
- Abnormality of the coagulation cascadeHPOHP:0003256
- Frequent (30% to 79% of cases)
- CholestasisHPOHP:0001396
- Frequent (30% to 79% of cases)
- Conjugated hyperbilirubinemiaHPOHP:0002908
- Frequent (30% to 79% of cases)
- Dark urineHPOHP:0040319
- Frequent (30% to 79% of cases)
- Decreased circulating vitamin E concentrationHPOHP:0100513
- Frequent (30% to 79% of cases)
- Elevated circulating alkaline phosphatase concentrationHPOHP:0003155
- Frequent (30% to 79% of cases)
- Elevated circulating hepatic transaminase concentrationHPOHP:0002910
- Frequent (30% to 79% of cases)
- Extramedullary hematopoiesisHPOHP:0001978
- Frequent (30% to 79% of cases)
Show the remaining 15
- Failure to thriveHPOHP:0001508
- Frequent (30% to 79% of cases)
- Fat malabsorptionHPOHP:0002630
- Frequent (30% to 79% of cases)
- Hepatic failureHPOHP:0001399
- Frequent (30% to 79% of cases)
- Hepatic steatosisHPOHP:0001397
- Frequent (30% to 79% of cases)
- HepatomegalyHPOHP:0002240
- Frequent (30% to 79% of cases)
- Increased circulating lactate dehydrogenase concentrationHPOHP:0025435
- 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.
- AKR1D1HGNC:388
- Definitive · ClinGen · Autosomal recessive · 2024
- Definitive · G2P · Autosomal recessive · 2015
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2022
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
7 names
Resolves to: congenital bile acid synthesis defect 2
- Also called
- AKR1D1 congenital bile acid synthesis defectBASD2bile acid synthesis defect, congenital, type 2CBAS2cholestasis with delta(4)-3-oxosteroid 5-beta-reductase deficiencycongenital bile acid synthesis defect caused by mutation in AKR1D1congenital bile acid synthesis defect type 2