As someone who has studied genetics on my own for the last twenty years I am very glad to read this editorial.
For example, take a population of 100 people, and let us say one of them has gene changes in their Fatty Acid Desaturase genes (FADS1 an d FADS2) that change how important Long Chain Omega 3 Fatty Acids (like from fish) are for them. This happens more often in people from indigenous arctic populations.
So the researcher tests if omega 3 effects cardiovascular outcome in these hundred people by adding a lot more fish oil to the diet of these 100 people. Since only one of them really needs it, the P value will be insignificant and everyone will say fish oil does nothing. Yet for that one person it was literally everything.
This is talked about only quietly in research, but I think the wider population needs to understand this to know how useless p < 0.05 is when testing nutritional effects in genetically diverse populations.
For example, take a population of 100 people, and let us say one of them has gene changes in their Fatty Acid Desaturase genes (FADS1 an d FADS2) that change how important Long Chain Omega 3 Fatty Acids (like from fish) are for them. This happens more often in people from indigenous arctic populations.
https://www.sciencedirect.com/science/article/pii/S000291652...
So the researcher tests if omega 3 effects cardiovascular outcome in these hundred people by adding a lot more fish oil to the diet of these 100 people. Since only one of them really needs it, the P value will be insignificant and everyone will say fish oil does nothing. Yet for that one person it was literally everything.
This is talked about only quietly in research, but I think the wider population needs to understand this to know how useless p < 0.05 is when testing nutritional effects in genetically diverse populations.
Interpreting Clinical Trials With Omega-3 Supplements in the Context of Ancestry and FADS Genetic Variation https://www.frontiersin.org/journals/nutrition/articles/10.3...