TFF1 and adenoma: PCR analysis of individual adenomas from TMX-treated Tff1-CreERT2;Rnpc3lox/lox;Gp130F/F mice, identified cells with either a Rnpc3lox/lox or Rnpc3lox/Δ genotype, but no cells with a Rnpc3Δ/Δ genotype, where Δ represents a deleted (null) allele (Fig. EV2I).