Definition

The LCT gene encodes lactase-phlorizin hydrolase, which breaks down lactose into glucose and galactose in the villi of the small intestine. The test does not actually examine the LCT gene itself, but rather the -13910C>T variant located in a regulatory region in the intron of the neighboring MCM6 gene; the C allele is associated with lactase expression shutting off in adulthood, while the T allele is associated with lactase persistence.

Gene/region examined

LCT/MCM6 - c.-13910C>T

Method

Sequence analysis

Accepted sample types

EDTA blood

Inheritance

Inherited as an autosomal recessive variant (C/C genotype); lactase non-persistence is recessive, while persistence is dominant in its effect.

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VUS (Variant of Uncertain Significance)

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