In pre-clinical mouse models, genetic deletion of the P2X7 receptor, which was previously described as being upregulated in ALS microglia (D’Ambrosi et al., 2009), resulted in increased motoneuron loss, increased microgliosis, and accelerated disease progression, thus suggesting an unanticipated protective role for the P2X7 receptor (Apolloni et al., 2013). The gene discussed is P2RX7; the disease is amyotrophic lateral sclerosis.