During Crohn’s disease, in addition to its stage, we observed significantly lower concentrations of β-endorphin compared to the concentration in the control group of 47.2 (34.4–57.5) pg/mL (p = 0.007 between CD1 and C and p < 0.0001 in both the CD2 and CD3 groups versus the control group (C)) (Figure 1). This evidence concerns the gene CD2 and Crohn disease.