For comparative analyses, we also included the data previously obtained for the PD-1-deficient patient and his healthy sibling (aged 10 and 6 years, respectively) (Ogishi et al., 2021), patients with a STAT1 gain-of-function (GOF) mutation (N = 1), a STAT3 GOF mutation (N = 1), activated PI3K delta syndrome (APDS; N = 2), and multisystem inflammatory syndrome in children due to RNaseL deficiency (MIS-C; N = 1) (Lee et al., 2023), together with seven healthy adult controls and six pediatric controls. The gene discussed is STAT1; the disease is COVID-19–associated multisystem inflammatory syndrome in children.