What is it about?
The risk of someone developing Alzheimer's disease is known to be increased if they have a family history of it. The best known genetic risk factor is different variants of the APOE gene. One of the variants increases your risk, another decreases it. We set out to see what effect the increased risk variant had in young to middle aged adults on nerve cell junctions. Increasingly scientists are thinking that dementia is the last stage in a process that takes 15-20 years to develop, so we wanted to look at the earliest stages of that. We didn't find any effect of the increased risk variant, but instead we found that the decreased risk variant was associated with some changes. These changes might possibly go some way towards explaining why these people have a lower risk of Alzheimer's disease.
Why is it important?
Most work on Alzheimer's disease has looked at people either with the disease or at high risk of it. Our results suggest that looking at people with a reduced risk might also be helpful for understanding this disease and, possibly, developing new treatments in the future.