We observed that expression of many of the chemokines and their receptors (CCL4, CCL5, CXCL1, CXCL2, CXCL3, CXCL6, CXCL8, CXCR1, and CXCR2) were altered in PTSD patients. The gene discussed is CXCL2; the disease is post-traumatic stress disorder.