This study focused on the association between plaque psoriasis and polymorphisms of several inflammation genes. Included in the study were 142 Caucasian (Czech) patients with plaque psoriasis and 141 healthy subjects. The genotypes of the polymorphisms in angiotensinogen [M235T ATG, A(-6)G ATG], in transporters associated with antigen processing TAP1 (TAP1*0101, TAP*02011 and TAP1*0301) and in lymphotoxin alpha (TNFbeta) (NcoI in intron 1) were detected by polymerase chain reaction-based methods and restriction enzyme analysis. An increase in B1 (less frequent) allele of NcoI TNFbeta polymorphism was found in psoriatic patients compared to healthy individuals (odds ratio = 1.6, 95% confidence interval 1.13-2.26, P = 0.006). A positive family history of psoriasis was associated with a higher B1 allele frequency in NcoI TNFbeta (P = 0.011). Hardy-Weinberg disequilibrium was found in TAP1 polymorphism A-->G at nucleotide 1207 in psoriatic patients. A case-control difference was found in the allelic concurrence of M235T and A(-6)G ATG polymorphisms. The most frequent population genotypes MMGG, MTAG and TTAA were observed in 92% of patients vs 74% of control subjects (odds ratio 0.29, 95% confidence interval 0.14-0.60, P = 0.0003). A positive history of tonsillitis and/or tonsillectomy was associated with a higher T allele frequency of the M235T ATG polymorphism (P = 0.037) as well as with a higher G allele frequency of the A(-6)G ATG polymorphism (P = 0.022). Polymorphisms in proinflammatory angiotensinogen and TNFbeta genes were associated with plaque psoriasis, a positive family history of psoriasis and with frequent tonsillitis in childhood.