SMAD3 and infectious otitis media: This group of genes represented a large fraction of all differences found between nuclear β-catenin-positive (ApcMin/+ and AOM) and negative (Smad3-/- and Tgfb1-/-; Rag2-/-) tumors (approximately 45%; 1,636 out of 3,592 features), as well as differences detected between early (that is, E13.5-E15.5, ED) and late (E.16.5-E18.5, LD) embryonic colon developmental stages.