Interestingly, in a series of studies by the same research group with overlapping patient populations(30,31,40), insulin/glucose AUC was more reduced and patterns of response more abnormal compared with controls during an OGTT than in an IVGTT, and a pattern of delayed insulin secretion in malnutrition was common; both these could indicate that part of the impaired insulin response was due to factors in the intestine. This evidence concerns the gene INS and nutritional deficiency disease.