Researchers at the University of Michigan, U.S.A, investigated the effect of tumor necrosis factor (TNF) polymorphisms on the response to anti-TNF and other systemic therapies for the treatment of psoriasis. Patients (n = 683) who received TNF blockers (adalimumab, etanercept, infliximab) and/or systemic agents (acitretin, alefacept, ciclosporin, efalizumab, methotrexate, psoralen UVA, UVB) were included in the study. Following self-evaluation of the treatment using a visual analogue scale a poor response was identified in 28%. Analysis of an allelic association between the response and the genotype for 4 single nucleotide polymorphisms (SNPs) in the TNF gene promoter region showed a moderate association between adalimumab and TNF(-1031 T/C) genotypes and between acitretin responders and TNF(-857C/T). However, ...