As far as we know, only 1 meta-analysis has been carried out to assess the correlation between TNF-α polymorphisms and JIA, the authors concluded that there was no association between the A allele (the variant allele) of TNF-α 238A/G or TNF-α 308A/G and JIA in European populations.[16] However, the sample size of that meta-analysis was not large enough, and they included an article that did not fit the inclusion criteria. This evidence concerns the gene TNF and juvenile idiopathic arthritis.