Studies have found that circulating EV counts are significantly increased in patients with Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS, debilitating disease with multiple symptoms, including pain, depression, and neurocognitive deterioration in function) and that circulating EV counts correlate significantly with serum C-reactive protein levels and have reported that circulating EV counts and EV-specific proteins can be used as novel biomarkers for the diagnosis of ME/CFS [52]. This evidence concerns the gene CRP and major depressive disorder.