Fig. 1Genotypes of the tumor necrosis factor (TNF)-α polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). (A) The NCO1 restriction enzyme recognize and cut the PCR product of the G-type allele into 2 fragments. Lane 1, A/A; lane 2, A/G; lane 3, G/G; lane M, 50-base pair ladder. (B) Sequencing analysis shows three genotypes at the -G308A site of the TNF-α gene: homozygotes with G/G (upper panel) and A/A (bottom panel) genotypes and a heterozygote with the A/G (middle panel) genotype.
Fig. 2Genotypes of the tumor necrosis factor (TNF)-β polymorphism by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). (A) SSCP demonstrating bands of each genotype. Lane 1, A/A; lane 2, A/G; lane 3, G/G. (B) Sequencing analysis shows three genotypes at the +G252A site of the TNF-β gene: homozygotes with G/G (upper panel) and A/A (bottom panel) genotypes and a heterozygote with the A/G (middle panel) genotype.
Fig. 3Odd ratios of assembled genotypes between osteoarthritis (OA) patients and controls. All genotypes with the A allele of the tumor necrosis factor (TNF) gene carry more than a tenfold increase in the risk of OA compared with those genotypes with the G allele of both the TNF-α and TNF-β genes.
Table 1Genotype and allele distributions of the TNFA -G308A gene polymorphism in OA patients and controls
Table 2Subgroup analysis of TNFA -G308A genotype percentages for OA patients and controls
Table 3Genotype and allele distributions of the TNFB +G252A gene polymorphism in OA patients and controls
Table 4Subgroup analysis of TNFB +G252A genotype percentages for OA patients and controls