I am pretty sure that my wife and I are genetically designed for different diets. I feel terrible if I go too long without a large serving of meat, and she feels terrible if she goes too long without large serving of vegetables.
I tried fish oil for a while when people were touting it. Didn't seem to do anything for me.
It doesn't sound like they're very clear on which gene is responsible for allowing the Inuit to only eat fish and meat with no ill effects.
It would be great to be able to get a DNA test and know which foods would be most healthy for that particular individual. Just from this article, there seems to be too many unknowns for that to be happening for a quite some time.