CSN1S1

Chr 4

casein alpha s1

Also known as: CASA, CSN1

NCBI Gene: 1446 ENSG00000126545 UniProt: P47710

The protein is a major milk protein with an important role in the capacity of milk to transport calcium phosphate. Mutations cause autosomal recessive congenital lactase deficiency, which presents in infancy with severe diarrhea, dehydration, and failure to thrive when exposed to lactose-containing milk. The gene shows very low constraint to loss-of-function variants, consistent with its specialized role in milk composition rather than essential cellular functions.

ResearchSummary from RefSeq, UniProt

Predicted to be involved in several processes, including response to 11-deoxycorticosterone; response to dehydroepiandrosterone; and response to progesterone. Located in extracellular space. [provided by Alliance of Genome Resources, Jul 2025]

ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

—

P/LP submissions

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P/LP missense

1.71

LOEUF

Mechanism· predicted

Some data sources returned errors (1)

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