congenital lactase deficiency
Findings
No curated finding names congenital lactase deficiency yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Congenital lactase deficiency is a rare severe gastrointestinal disorder in newborns primarily reported in Finland and characterized clinically by watery diarrhea on feeding with breast-milk or lactose-containing formula.
Definition from the Mondo Disease Ontology (MONDO:0009115), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Neonatal onset
HPO, annotations 2026-09-02
Features
5 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.
- Decreased small intestinal mucosa lactase levelHPOHP:0025130
- Congenital onset
- DehydrationHPOHP:0001944
- DiarrheaHPOHP:0002014
- Lactose intoleranceHPOHP:0004789
- Metabolic acidosisHPOHP:0001942
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.
- LCTHGNC:6530
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2020
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Moderate · Ambry Genetics · Autosomal recessive · 2020
- Supportive · Orphanet · Autosomal recessive · 2021