Three of these were upregulated in DA.F344(Cia5d) FLS (Ncor1, Trim41, and Gtlf3b) and two were downregulated in DA.F344(Cia5d) (Trpv2 and Trim16), raising the possibility that a polymorphism/mutation in one of these genes could explain the arthritis and FLS invasive phenotypes attributed to Cia5d. Specifically, a polymorphism in a regulatory element or intron in one of these genes, or in another gene in the region, could influence transcription, thus explaining differences in levels of mRNA and disease. This evidence concerns the gene NCOR1 and arthritic joint disease.