Among the 66 full-text articles, reviews, or meta-analysis reviewed, 33 articles were biochemical studies; 16 articles studied non-cancer diseases such as depression; five articles analysed several P2RX7 polymorphisms that were not studied in other independent studies, resulting in the impossibility of data pooling; and four articles failed to provide sufficient data for calculation. Here, P2RX7 is linked to depressive symptom measurement.