We utilized an established transgenic mouse model of MERS-CoV pathogenesis for these studies where the murine ortholog of the human receptor, dipeptidyl peptidase 4 (DPP4) was humanized at residues 288 and 330 (288/330+/+ mice) to facilitate infection and pathogenesis reminiscent to that in humans [12]. The gene discussed is DPP4; the disease is infection.