A new study has revealed that genetics may play a more significant role in the development of Alzheimer’s disease than previously thought.<\/p>\n
The research, led by the University of Glasgow<\/a>, published in the journal npj Dementia, found that while better memory, reasoning, and reaction times were linked to a lower risk of Alzheimer\u2019s disease up to 15 years later, this protective effect was significantly reduced in people with a higher genetic risk.<\/p>\n Researchers focused on the APOE e4 genotype, which is present in roughly one in four people and is the strongest known genetic predictor of late-onset Alzheimer\u2019s.<\/p>\n Read more:\u00a0Glasgow drugs trial to use genetics to ‘personalise’ treatments\u00a0<\/a><\/p>\n A single copy of the APOE e4 gene increases Alzheimer\u2019s risk threefold, while two copies raise the risk by twelvefold.<\/p>\n Dr Donald Lyall, senior lecturer in population brain health at the University of Glasgow<\/a>‘s School of Health<\/a> and Wellbeing, said: “Our study adds to the knowledge gap that exists on the relationship between genetic factors, cognitive health generally, and subsequent risk of dementia in later life.<\/p>\n “Our findings suggest that genetics plays a more significant role than previously thought and may influence the risk or protection conferred by other factors like premorbid cognitive health.”<\/p>\n In the study, people with above-average reasoning ability were found to have a 36%\u00a0lower risk of developing Alzheimer\u2019s within 15 years.<\/p>\n However, for those who also carried the APOE e4 gene, the risk reduction dropped to just 21%.<\/p>\n More strikingly, individuals with high reasoning skills but who carried the APOE e4 genotype were more likely to develop Alzheimer\u2019s than those with below-average reasoning but no genetic risk factor.<\/p>\n The researchers analysed data from over 252,000 UK Biobank participants aged 55 and older, with the average age at the start of the study being just over 62.<\/p>\n To ensure long-term accuracy, individuals diagnosed with Alzheimer\u2019s within two years of testing were excluded.<\/p>\n Researchers excluded individuals diagnosed with Alzheimer\u2019s within two years of cognitive testing.<\/p>\n The study reinforces the challenges in identifying effective therapies for Alzheimer\u2019s, particularly given the influence of genetic factors.<\/p>\n