Medical Research: What is the background for this study? What are the main findings?
Dr. Barral: We already know that there is a substantial genetic contribution to the variability observed in different cognitive tasks including memory performance. Previous work reported heritability estimates for episodic memory ranging between 30% and 60%. However, we can’t fully explain why some individuals demonstrate a better memory performance in late life, while others do not.
We have previously defined a cognitive endophenotype based on exceptional episodic memory performance (EEM) and demonstrated that there is a familial aggregation of EEM in families selected on their basis of their exceptional survival, the Long Life Family Study. We performed genome-wide linkage analysis of long-lived families selected on the basis of their exceptional episodic memory and the follow-up SNP association analysis with episodic memory in four independent cohorts of more than 4,000 non-demented elderly cohorts.
Our results provide strong evidence for potential candidate genes related to exceptional episodic memory on 6q24.
Medical Research: What should clinicians and patients take away from your report?
Dr. Barral: If we are able to identify genes that influence our memory, we will gain a better understanding of the biological basis of memory performance that will allow interventions for enhancement of cognitive function.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Barral: The region on chromosome 6q24 associated with episodic memory contains several biological candidate genes. The next logical step would be to sequence the region to be able to identify the specific genetic variants that explain the variability in memory performance.
Common Genetic Variants on 6q24 Associated With Exceptional Episodic Memory Performance in the Elderly
Barral S1, Cosentino S1, Christensen K2, Newman AB3, Perls TT4, Province MA5, Mayeux R1; for the Long Life Family Study.
JAMA Neurol. 2014 Dec 1;71(12):1514-1519. doi: 10.1001/jamaneurol.2014.1663.