Betacellulin is a member of the epidermal growth factor (EGF) family and may play a role in islet neogenesis and regeneration. To evaluate whether polymorphisms in this gene are associated with type 2 diabetes (T2DM) and impaired glucose tolerance (IGT), we genotyped 7 previously identified betacellulin variants in Amish subjects with T2DM (n=150), IGT (n=148) and normal glucose tolerance (NGT) (n=361). There were no significant differences in the allele frequencies of the variants among the 3 groups. In an expanded set of 729 nondiabetic Amish subjects, there was no significant association between the betacellulin variants and levels of glucose or insulin either fasting or during a 3 h oral glucose tolerance test, HOMA or insulin secretion index. These results are consistent with previous studies in Caucasian populations and suggest that variants in the betacellulin gene do not play a major role in the development of T2DM in Caucasian populations.