Dr Kirsty Lu of UCL, first author on the study, said: “Previous evidence has suggested that the APOE4 gene is one of various genetic variants that cause harm late in life, but may confer benefits earlier in life, during or before reproductive years. Here we have found that APOE4’s benefits may in fact persist into old age, at the same time that the harms of Alzheimer’s disease are beginning to develop.”
Dr Susan Kohlhaas, Director of Research at Alzheimer’s Research UK, the study’s funders, said: “Alzheimer’s disease is the most common cause of dementia and a combination of risk factors including our age, lifestyle, and genetics play a role in determining our individual risk. We know the APOE4 gene can increase our overall risk of developing Alzheimer’s but having a copy doesn’t mean people will definitely go on to develop the disease.
“This new research highlights that there is still a lot to be understood about these genes, their role in the development of Alzheimer’s, and intriguingly what effects they may have beyond the disease. While this research may be of little comfort for those living with Alzheimer’s, better understanding the most impactful Alzheimer’s risk gene is crucial for building a more complete picture of the development of the disease.
“While we cannot change our age or genes, some research has found that even if you carry a risk gene, there are still things you can do to reduce your risk.”