These responses were abrogated by the co-administration of a selective TYK2 inhibitor (Edelkamp, 2021), which confirms a key role of IL-12, whose receptor utilizes a TYK2 and Janus kinase 2 pair for downstream signal transduction (Ullrich et al., 2020; Krueger et al., 2022), These preliminary findings suggest that IL-12 is a key effector cytokine in promoting pathogenic IFN-γ secretion and HF-IP collapse. The gene discussed is JAK2; the disease is hydrops fetalis.