Polymorphisms Of Tumor Necrosis Factor Alpha Promoter Gene And Its Correlation With Psoriasis Vulgaris Of The Han Nationality In Yunnan Province

Objective To investigate the gene polymorphisms of tumor necrosis factor α (TNF-α) promoter region in patients with psoriasis vulgaris (PsV) and their relationship to the ages at onset of psoriasis.Methods 77 well-characterized patients with PsV and 82 healthy controls in Yunnan Chinese Han were studied. Polymorphisms of the DNA fragment from -499 to +53 of the TNF-α promoter gene were detected by polymerase chain reaction (PCR) and the products were directly sequenced.Results TNFa-238.2 was significantly increased in frequency in PsV compared with controls (16.9% Vs 3.9%, P=0.006, OR=5.349 [95%CI 1.461 , 19.586]), especially in juvenile onset psoriasis (25% Vs 3.9%, P=0.003, OR=8.167 [95%CI 1.720,38.769]) . However, the frequency of TNFα-308.2 was significantly decreased in type I psoriasis (4.2% Vs 17.6%, P=0.033) though there was no statistical significance between total PsV group and control group (5.2% Vs 13.4%, P=0.076). Also, our results showed that the frequency of TNF238.2 between early and late onset psoriasis are obviously different (25% Vs 3.4%, P=0.025 ,OR=9.333[95%CI 1.144 ,76.136]. In addition, the results showed that gender and family history have no influence on the polymorphisms of TNF-238A and TNF-308A.Conclusions This study demonstrated that there was association between the polymorphisms of TNF-238A and the early onset psoriatic vulgaris in Han population of Yunnan province, and the TNF238.2 allele mutation might be one factor to predispose type I PsV. The findings also provide evidence that patients with early and late onset psoriasis differ in their genetic background. Further investigation should be required to prove this.