Immunoblots confirmed expression of Smad4 full-length protein (61 kDa) in both Smad4+/+ and Smad4+/Δ adenomas, with a smaller band of (43 kDa) detected in protein extracts from Smad4+/Δ and Smad4Δ/Δ adenomas (Supplementary Fig. 2). The gene discussed is SMAD4; the disease is adenoma.