Abstract
INTRODUCTION: Gulf War illness (GWI) is an environmentally-triggered chronic multisymptom illness typified by protean symptoms, in which mitochondrial impairment is evident. It has been likened to accelerated aging. Nuclear genetics of detoxification have been linked to GWI. OBJECTIVE: To see whether mitochondrial (mt) haplogroup U - a heritable profile of mitochondrial DNA that has been tied to aging-related conditions - significantly predicts greater GWI severity; and to assess whether GWI severity is influenced by mitochondrial as well as nuclear genetics. 54 consenting Gulf War veterans gave information on GWI severity, of whom 52 had nuclear DNA assessment; and 45 had both nuclear and mitochondrial DNA assessments. Regression with robust standard errors assessed prediction of GWI severity as a function of nuclear genetics (butyrylcholinesterase variants), mitochondrial genetics (haplogroup U, previously tied to aging-related conditions); or both. RESULTS: BChE "adverse" variants significantly predicted GWI severity (β(SE) = 23.4(11.4), p = 0.046), as did mt haplogroup U (β(SE) = 36.4(13.6), p = 0.010). In a model including both, BChE was no longer significant, but mt haplogroup U retained significance (β(SE) = 36.7(13.0), p = 0.007). This is the first study to show that mitochondrial genetics are tied to GWI severity in Gulf-deployed veterans. Other data affirm a tie to nuclear genetics, making GWI indeed a "tale of two genomes."