Anti-agrin antibodies (Y5 in Figure 1) have been detected in some of MG patients with or without antibodies against AChR, MuSK, and Lrp4 (Gasperi et al., 2014; Zhang et al., 2014; Cordts et al., 2017; Yan et al., 2018b). The gene discussed is AGRN; the disease is myasthenia gravis.