Lau MYZ, et al. - Researchers used data from the Tasmanian Longitudinal Health Study and the Melbourne Atopy Cohort Study to assess the link between polymorphisms in the CD14 gene and allergic sensitisation, and to determine if this link was altered by sibling exposure, as a marker of microbial exposure. The links were evaluated by using logistic regression and multi-level mixed-effects logistic regression. They used random-effects meta-analysis to pool effect estimates across the cohorts. They observed that, in genetically susceptible individuals, cumulative sibling exposure reduced the risk of sensitisation from childhood to middle age. In those with the rs5744455-C-allele vs the T-allele, 20.9% smaller odds of sensitisation were observed with increasing cumulative exposure to sibling before 6 months of age, a finding by pooled meta-analysis.