In this regard, a polymorphism in the promoter region of the IGF-I gene was associated with low levels of IGF-I and increased risk of type-2 diabetes mellitus.[21] In addition to this, IGF-I binding proteins (IGFBPs) were not measured, which play an important role in regulating the bioavailability of IGF-I. The gene discussed is IGF1; the disease is type 2 diabetes mellitus.