Validating Gulf War Illness Blood Biomarkers

Inclusion Criteria: 1. Age 35 years or older. 2. For GWI cases, served in the 1990-1991 Gulf War as active duty, national guard, or reserves and meet criteria for the CDC Chronic Multisymptom Illness (CMI) GWI definition or Kansas GWI definition. 3. For controls, must be a veteran in the same age range as those veterans with GWI as defined above. 4. Ability to understand written and spoken English or availability of a legal representative who can understand written or spoken English. Participants and caregiver/informants must be able to read, write and speak the language in which psychometric tests are provided with visual and auditory acuity (corrected) sufficient to allow for accurate testing. Exclusion Criteria: 1. Diagnosed or being treated by a physician for any of the following (Steele et al, 2000) and deemed clinically significant per the discretion of the PI: 1. Cancer (except for non-melanoma skin cancers) 2. Chronic infectious disease 3. Problems resulting from postwar injuries. 4. Liver disease 5. Lupus 6. Multiple sclerosis 7. Stroke 8. Serious psychiatric condition (those associated with psychosis and/or for which the respondent had been hospitalized since 1991). 9. Dementia or any type of Parkinson's disease (PD). 2. Hospitalized in the last 5 years for alcohol or drug dependence, depression, or post-traumatic stress disorder (PTSD). 3. Female subject is either pregnant or nursing.