With respect to the immune response against intracellular bacteria such as C. burnetii, it is of interest that CXCR3-chemokines have also been examined as candidate markers for the differentiation between active and latent tuberculosis [17], as a possible alternative for IFN-γ release assay (IGRA) in latent tuberculosis [18] and for follow-up of tuberculosis treatment [19]. The gene discussed is CXCR3; the disease is tuberculosis.