Inconsistencies among study results might in part be due to the retrospective character, the relatively small study populations or the focus on MBL2 gene polymorphisms but not on actual MBL plasma levels, which would implicate the MBL deficiency and which are also influenced by non-genetic factors such as inflammation43 and thyroid function44. The gene discussed is MBL2; the disease is hyperinsulinemic hypoglycemia, familial, 4.