PoliovirusLes poliovirus, agents responsables de la poliomyélite, appartiennent au genre Enterovirus. À la suite de nombreuses études dont il a fait l'objet depuis les années 1930 et particulièrement dans les années 1950, le poliovirus humain est devenu un modèle de choix pour l'étude de la biologie moléculaire des virus animaux à ARN. Chaque sérotype ou souche contient de nombreuses sous-souches.
Genotype-first approachThe genotype-first approach is a type of strategy used in genetic epidemiological studies to associate specific genotypes to apparent clinical phenotypes of a complex disease or trait. As opposed to “phenotype-first”, the traditional strategy that has been guiding genome-wide association studies (GWAS) so far, this approach characterizes individuals first by a statistically common genotype based on molecular tests prior to clinical phenotypic classification.
Gene–environment interactionGene–environment interaction (or genotype–environment interaction or G×E) is when two different genotypes respond to environmental variation in different ways. A norm of reaction is a graph that shows the relationship between genes and environmental factors when phenotypic differences are continuous. They can help illustrate GxE interactions. When the norm of reaction is not parallel, as shown in the figure below, there is a gene by environment interaction. This indicates that each genotype responds to environmental variation in a different way.