Surprisingly, multiple studies supported our hypothesis that G9A may promote keratinocyte proliferation and inhibit cell apoptosis, particularly in Tine et al.’s study, which mentioned that the ability of N-WASP seemed as the upstream of G9A, according to Li, Hui’s research, to promote keratinocyte proliferation brought an adverse expectation on function of N-WASP in psoriasis. This evidence concerns the gene EHMT2 and psoriasis.