IFNA1 and interstitial lung disease: A severe inflammatory phenotype of SAVI is induced by gain-of-function mutations in STING1, which encodes STING (stimulator of IFN genes); this phenotype is characterized clinically by skin vasculopathy, systemic inflammation, and lung involvement (e.g., interstitial lung disease or diffuse alveolar hemorrhage), which is associated with high morbidity and mortality (128, 129).