Abstract: Objective To investigate the relationship between polymorphic site A667V of 5,10-methylenetetrahydrofolate reductase (MTHFR) gene and psoriasis. Methods PCR-RFLP method was used to detect the polymorphism of MTHFR gene in 3 psoriasis pedigrees and 39 psoriatics. Results Genotype frequencies of the psoriastics were A/A-20.51%, A/V=48.72%and V/V=30.76%;the allelic frequencies were A=0.4487 and V=0.5513. Conclusion There is a significant difference of MTHFR gene thermolabile defect between the psoriatics and the control, and our results demonstrate MTHFR gene is related to A667V mutant.

Key words: Psoriasis, Tetrahydrofolate dehydrogenase, PCR-RFLP