Insulin and IGF play an important role in brain function and structure.5 Insulin, IGF-1 and IGF-2polypeptides and receptor genes are expressed in neurons34 and glia,35,36 particularly instructures that are targeted in neurodegenerative diseases.34,35,37 IGF and insulinare associated with regulating and maintaining cognitive function,38 and participate in neuronal andglial functions such as growth, metabolism, survival, gene expression, proteinsynthesis, cytoskeletal assembly, neurotransmitter function, synapse formation andplasticity.34,39. This evidence concerns the gene IGF1 and neurodegenerative disease.