Differences between men and women with recent-onset axial SpA were reported in a prospective multicentre French cohort, where women had higher disease activity despite having less radiographic sacroiliitis or MRI inflammation, more peripheral involvement and more family history, whereas male gender was frequently related to positive HLA-B27 antigen, elevated CRP, and MRI inflammation of the spine [36]. The gene discussed is CRP; the disease is Sacroiliac arthritis.