Lack of Association between LCT_rs140433552*CA>del Indel Polymorphism and Lactose Intolerance in a Southern Brazilian Population

Abstract

Background/Aims: Polymorphisms in the enhancer of the lactase gene (LCT) are strongly associated with lactase persistence, but not always predictive of the phenotype. We investigated a possible association between the regulatory rs140433552*CA>del variant of LCT and lactose intolerance (LI). Methods: We genotyped 122 individuals for rs140433552 and rs4988235 (–13910*C>T). Results: Associations of rs140433552*CA>del with LI depend on –13910*C>T. Homozygous individuals for the C-CA haplotype, as well as C-CA+/C individuals, seem more likely to manifest LI (OR 3.33 [95% CI 1.32–8.35], p = 0.011, and OR 3.93 [95% CI 1.61–9.61], p = 0.003, respectively), while homozygous individuals for the T-CA haplotype seem more likely to be lactose tolerant (OR 0.04 [95% CI 0.002–0.70], p = 8 × 10–4). Conclusions: rs140433552*CA>del is not independently associated with LI.

Keywords

• rs140433552*ca>del
• indel
• 3′ untranslated region
• lct
• haplotypes
• lactose intolerance
• genetic susceptibility