All 25 patients in our retrospective chart review met the criteria for a clinical diagnosis of Lyme disease supported by a physician-documented erythema migrans (EM) rash and/or positive laboratory testing, including a positive ELISA/enzyme immunoassay (and/or C6 ELISA), immunofluorescent antibody (IFA), Centers for Disease Control and Prevention (CDC) positive IgM and/or IgG Western blot (WB), PCR, Borrelia-specific bands (23, 31, 34, 39, 83/93) on a WB [92,93], and/or positive ELISpot (lymphocyte transformation test (LTT)). The gene discussed is CD40LG; the disease is Lyme disease.