Indeed, higher expression levels of OCTN2, the protein encoded by SLC22A5, have been found in inflamed regions of the intestinal epithelium compared with non-inflamed areas, and a role of this protein in the intestinal homeostasis has also been reported46; whereas, given the relevance of the type 1 interferon signaling pathway in SSc, the IRF1 gene seems a more plausible candidate to be involved in SSc susceptibility. This evidence concerns the gene IRF1 and systemic sclerosis.