Evaluation Of Polygenic Risk Scores For A Possible Genetic Basis Of The Inverse Association Between Cancer And Cognitive Decline
It’s an intriguing observation: some studies suggest that people who develop cancer might have a lower risk of cognitive decline, and vice versa. What if there’s a common thread, a shared biological mechanism that influences both? This question led researchers to explore the underlying genetic connections.
To investigate this, scientists used a tool called “polygenic risk scores.” Imagine your DNA as a vast instruction manual. A polygenic risk score is essentially a way to sum up the tiny contributions from many different genetic variations across your entire instruction manual to estimate your overall inherited likelihood for developing a specific disease.
In this research, scientists calculated polygenic risk scores for various cancers and for Alzheimer’s disease in a large group of individuals. Their goal was to see if a higher genetic predisposition for cancer was linked to better cognitive function, or if a higher genetic risk for Alzheimer’s was associated with a lower cancer risk.
The findings revealed a nuanced picture. In one significant cohort, a higher genetic predisposition for cancer was nominally associated with improved “fluid intelligence” – essentially, your ability to think on your feet, solve new problems, and understand complex information. This suggests that some genetic factors that increase cancer risk might also contribute to better cognitive performance. Interestingly, specific genetic variants within the human leukocyte antigen (HLA) complex, which plays a crucial role in our immune system, were particularly associated with this effect.
However, the study did not find a significant link between a higher genetic risk for Alzheimer’s disease and a lower risk of cancer. While these results are not definitive, they offer a fascinating glimpse into the complex interplay between our genes, cancer, and brain health, suggesting that shared biological pathways, possibly involving immune surveillance, could be at play. This opens new doors for understanding how these major diseases might be connected at a fundamental biological level.