Pro-inflammatory proteins at baseline were significantly higher in patients than controls after adjustment for gender, age, childhood adversity and BMI: independent effects of markers elevated in TRD patients: IL-6 X2 = 0.061 [95% CI 0.005, 0.719], p = 0.026; TNFα X2 = 0.005 [95% CI 0.0009, 0.554], p = 0.028; CRP X2 = 0.119 [95% CI 0.027, 0.526], p = 0.005. This evidence concerns the gene IL6 and treatment resistant depression.