Indeed, in patients with immunodysregulation polyendocrinopathy enteropathy X-linked (IPEX) syndrome due to FOXP3 mutations, or in patients with IPEX-like diseases caused by mutations in related genes (Halabi-Tawil et al., 2009; Goudy et al., 2013), psoriasis-like skin inflammation and epidermal infiltration by CD8+ T cells are some of the earliest and most severe features (Halabi-Tawil et al., 2009; Goudy et al., 2013). The gene discussed is CD8A; the disease is psoriasis.