In the lungs of both C57BL/6J and C57BL/6NJ mice, we observed up-regulation of six genes with established coding region differences between these mouse strains (Chl1, Nlrp12, Plk1, Cyfip2, Adamts3, and Pdzk1), and we suggest that any of these genes potentially could control influenza disease susceptibility. This evidence concerns the gene CYFIP2 and influenza.