ZAP70 and severe combined immunodeficiency: For example, complete versus partial LOF mutations in ZAP70, LAT, and SLP76 lead to SCID versus CID with immune dysregulation phenotypes, respectively (Elder, 1997; Elder et al., 1994, 1995; Bacchelli et al., 2017; Keller et al., 2016; Lev et al., 2021; Chan et al., 2016; Hsu et al., 2009; Sommers et al., 2002).