To uncover any possible association between the functional polymorphisms of the cytokine genes and PJI, six selected SNPs (IL1B-511, IL1B + 3962, TNF-308, TNF-238, IL6–174, IL6 nt565) were genotyped in the TJA patients with/without PJI and in the ethnically matched healthy controls. The gene discussed is TNF; the disease is juvenile polyposis syndrome.