In addition, carrying the homozygous p.Leu1007fsX1008 NOD2 frameshift mutation had no effect on systemic CCL20 levels in patients with Crohn’s disease [univariable: β (95% CI) =  − 0.026 (− 0.443, 0.391), p = 0.90]. Here, CCL20 is linked to Crohn disease.