Accuracy of a Genetic Test for the Diagnosis of Hypolactasia in Chilean Children: Comparison With the Breath Test.

Background: Lactase nonpersistence (LNP) in humans is a genetically determined trait. This age-dependent decrease of lactase expression is most frequently caused by single nucleotide polymorphisms in the regulatory region of the lactase (LCT) gene. The homozygous LCT-13,910C/C genotype (rs 4988235) predominates in Caucasian adults with LNP, and is useful for its diagnosis in this population.

[Comparative performance of symptoms questionnaire, hydrogen test and genetic test for lactose intolerance].

Background: Genetically programmed adult-type hypolactasia affects 56% of Chilean population. Ideally, diagnosis should be confirmed.

Aim: To compare diagnostic yield of genetic test, hydrogen (H2) expiratory test and a validated symptomatic structured survey (SS).