Underlying the importance of genetic associations, previously a clear correlation has been shown between psoriasis and risk of the development of diseases with autoimmune background, such as rheumatoid arthritis (RA), type 1 diabetes, celiac disease, or Crohn's disease, based on the single nucleotide polymorphism (SNP) analysis of the TNFAIP3 gene [4]. Here, TNFAIP3 is linked to rheumatoid arthritis.