Carriers of This Gene Are Less Able to Recall Recently Learned Information, More Prone to Dementia
A new study published in the journal Scientific Reports has found that even people who don’t show any signs of memory problems like those related to Alzheimer’s disease may still have trouble recalling recently learned information if they carry a copy of a particular Alzheimer’s-related gene called APOE4.
The gene itself does not mean a person will get Alzheimer’s disease, although it does increase the risk of the disease. This finding may eventually help doctors determine patients’ risk level for Alzheimer’s disease or decide whether to test a particular patient for other signs of Alzheimer’s disease.
60 participants ages 40-61 were involved in the study, and all of them had a copy of the APOE3 or APOE4 gene, or both. They all had normal hearing and normal cognitive assessments, and they completed memory questionnaires before undergoing the study.
Researchers played 92 audio clips for the participants and asked them to identify which ear they heard the sound in. After an hour-long break, the clips were played again, twice—but the second time, there was an additional sound at the end. Participants were asked to identify whether there was an additional sound and had to press a button when they heard it.
All participants were able to successfully identify and remember which ear the sounds were coming from, but those who carried the APOE4 gene had a harder time determining whether there was an additional sound and when it occurred.
“For some reason, people with the APOE4 gene were not able to take advantage of information they learned earlier, such as the expected location of the clip, to boost their performance,” says Dr. Claude Alain, a senior author on the paper and senior scientist at Baycrest’s Rotman Research Institute. “This study shows we have a test that is sensitive to capture problems or challenges faced by individuals with this gene, before their deficits are observed on a standard neuropsychological assessment.”
The APOE4 gene increases the risk of developing Alzheimer’s disease by about 15 times, making it an important gene mutation to study and understand. Researchers believe their findings will change the future of early diagnosis and treatment of Alzheimer’s disease.
“The research could lead to more sensitive methods of detecting Alzheimer’s disease in its very earliest stages, the time at which treatments are most likely to be effective,” says Dr. Chris Butler, senior author and an associate professor in clinical neurosciences at the University of Oxford.
the researchers’ next step will be to study the same concept on people with mild cognitive impairments to see how the brain’s ability to process auditory information changes as the disease progresses.