However, researchers have recently realized that there is a continuum of phenotypes between M1 and M2 in ALS (Li et al., 2019), such as disease-associated microglia (DAM) (Krasemann et al., 2017; Dols-Icardo et al., 2020) and receptor-interacting protein kinase 1 (RIPK1)—regulated inflammatory microglia (RRIMs) (Mifflin et al., 2021). The gene discussed is RIPK1; the disease is amyotrophic lateral sclerosis.