In a recent work by Carini and others, the authors explored the genomic architecture of whole blood obtained from rheumatoid arthritis (RA) patients investigating a possible chromosome conformation signature (including IFNAR1, IL-21R, IL-23, IL-17A and CXCL13), before and after the administration of methotrexate (MTX) treatment. This evidence concerns the gene CXCL13 and rheumatoid arthritis.