Tian et al. (2014; TD = 46/NTD = 43) and Wu et al. (2022; TD = 121/NTD = 118) found (marginally) lower TNF-α blood levels in individuals with schizophrenia with and without TD, but (Boiko et al., 2017; TD = 71/NTD = 109; conference abstract) found no significant differences. The gene discussed is TNF; the disease is schizophrenia.