EGFR and gastroesophageal reflux disease: However, the EGF mRNA expression was significantly lower in GERD patients with the genotype combination AA-GG (EGF-EGFR; n = 4, of which RE = 2 and EAC = 2) than in carriers of any other combination (n = 19; logistic regression: p = 0.048, OR: 3.15, see Figure 4).