Further analysis of smoke-induced changes in CC gene expression demonstrate upregulation of genes responsible for mucin production (Muc4), inflammatory responses to viral infection (Apobec3), Atp8a1 (ATPase phospholipid transporting protein 8a1, involved in ion transport), Akr1b8 (aldo-keto reductase family member), and Resf1 (retroelement silencing factor 1). Here, MUC4 is linked to viral infectious disease.