Additionally, it has been demonstrated that IL-6 levels are associated with presence of internalization and externalization behaviors in children’s (Slopen et al., 2013; Tang et al., 2019), and that increase levels of the IL-6 in childhood are associated with an augmented risk of developing psychosis and depression in young adulthood (Khandaker et al., 2014; de Baumont et al., 2019; Perry et al., 2021). This evidence concerns the gene IL6 and major depressive disorder.