In baseline samples from ME/CFS patients (n = 70), the mean serum BAFF level was 981 pg/mL (95%CI 933–1029), while in healthy controls (n = 56) the median serum BAFF level was 899 pg/mL (95% CI 856–940) (p = 0.011) (Fig 1A). This evidence concerns the gene TNFSF13B and myalgic encephalomeyelitis/chronic fatigue syndrome.