Indeed, over-expression of distinct pro-inflammatory cytokines, including interleukin 1 beta (IL-1β), IL-6, and tumor necrosis factor alpha (TNF-α), has been associated with several neuropsychiatric disorders, such as depression (3, 4), as well as neurodegenerative diseases, like Alzheimer's (AD) and Parkinson's (PD) (5, 6). This evidence concerns the gene TNF and depressive symptom measurement.