Both GSK3B and MAPT genes control crucial processes in the cell. We have shown that genetic polymorphisms in these two genes interact to increase risk for late-onset, idiopathic neurodegeneration. We aim to discover whether the two genes will have an effect in other diseases and to determine the biological mechanisms in the genes act to increase disease risk. An interesting adjunct to this research is the examination of how ‘lifestyle’ factors, such as smoking and a diet of green leafy vegetables, can impact on how the two genes are expressed in our bodies. We are currently examining a large cohort of elderly Australians who have detailed records of their daily habits, to determine whether some lifestyle factors can significantly impact on the activity of GSK3B and MAPT.