In the present study, we observed that Crohn’s disease patients carrying the NOD2 rs2066844 variant had low functional activity of the MBL-MASP complex, suggesting that both the NOD2 rs2066844 variant and impairment of the functional activity of the MBL-MASP complex could affect the innate immune response against pathogens, leading to an increased risk of Crohn’s disease35, 36. Here, MBL2 is linked to Crohn disease.