Weight change and oxygen saturation decreased similarly in WT, HPS1, and HPS2 mice during the first 10 days postinfection (dpi) with H1N1 PR8 influenza; subsequently, oxygen saturations trended lower in HPS1 and HPS2 mice, though no mortality was observed in any group (Figure 2, B and C). The gene discussed is HPS1; the disease is influenza.