Coming back to a missing immune deviation as the main explanatory mechanism for the hygiene hypothesis.

摘要

The expression of the allergic phenotype is dependent on the interaction between 2 major factors: a genetic predisposition and gene-environment interactions. The pattern of allergic inheritance is that of a complex poly-genic disorder. The gene-environment interactions, however, heavily influence the development of atopic allergy, and several changes in lifestyle that have occurred over the past few decades are certainly responsible for the increased prevalence of allergy in Western countries. Several epidemiologic studies have clearly shown that modifications of the pattern of microbial exposure of children associated with Westernization represent a critical factor underlying the rising severity and prevalence of atopic disorders (the so-called hygiene hypothesis).