The existence of a common susceptibility gene for psoriasis/PsA and Crohn disease was recently demonstrated by evidence of association of CARD15 polymorphisms with PsA.
A meta-analysis was performed to survey studies on the NOD2/CARD15 polymorphisms and psoriasis/PsA using comprehensive PubMed, Embase, and Web of Science citation search.
We failed to observe any significant difference between patients and controls, thereby excluding the presence of a strong genetic association between CARD15 gene polymorphisms and psoriasis, in the Italian population.
Our study supported the involvement of six candidate genes in susceptibility to psoriasis: SCL12A8, which belongs to the solute carrier gene family; FLG and TGM5, which are involved in epidermal differentiation; CARD15 and CYLD, which modulate the transcription factor NF-kB; and IL1RN, which encodes an IL receptor antagonist.
CARD15, a major susceptibility gene for Crohn's disease (CD) on chromosome 16q, is an interesting candidate gene for psoriasis, because there is a documented clinical association of CD with psoriasis, and recently the association of CARD15 mutations with PsA was reported in Newfoundland population.