Many actin-regulatory proteins are targets of BCR signaling (Tolar, 2017) and mutations in actin regulators such as Wiskott-Aldrich Syndrome protein (WASp), Arpc1B, Hem1/NCKAP1L, and Wdr1 result in autoimmune or immunodeficiency syndromes that have been termed actinopathies (Kile et al., 2007; Kahr et al., 2017; Kuijpers et al., 2017; Brigida et al., 2018; Candotti, 2018; Pfajfer et al., 2018; Randzavola et al., 2019; Volpi et al., 2019; Cook et al., 2020; Sprenkeler et al., 2020). The gene discussed is NCKAP1L; the disease is alpha-actinopathy.