Five additional GWI participants were recruited but subsequently excluded from the study: three due to exclusionary blood test results, including a positive and high ANA, a high thyroid-stimulating hormone (TSH) level indicating a thyroid disorder, and a high erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level indicating a possible autoimmune disorder; one due to a HADS depression score above the study cut-off; and one because he did not experience any symptoms during the study period, which was highly atypical of his usual symptomatology. Here, BTG3 is linked to major depressive disorder.