RAG2 and infectious otitis media: Interestingly, a recent paper that examined gene expression in mouse models of colon carcinoma in a developmental context revealed a distinction between Smad3-/- and Tgfb1-/-; Rag2-/- models (both exhibiting a strong inflammatory component and showing similarity to late colon development) and ApcMin/+ and AOM models, which recapitulated early colon development [10].