Fig. 4.

Identification of epigenetically mediated genetic risk factors for psoriasis. a Possible relationship between causal factor (G), a possible mediator (M), and an outcome (Y). Top, the methylation-mediated relationship, in which genotype (G) acts on phenotype (Y) through methylation (M); middle, the consequential methylation model, in which DNA methylation (M) changes are the consequence of phenotype (Y); bottom, the independent model, in which the genotype (G) acts on DNA methylation (M) and phenotype (Y) independently. b The four components of the CIT. c Flow diagram and results for identifying epigenetically mediated genetic risk for psoriasis