When you look at dog breeds, there are many things that are common in certain breeds. German Shepherds are typically very fast learners and food motivated. *oodles are typically high strung and reactive to their environment. Of course, there are statistical outlyers to everything. And with time and effort, you can train dogs into or out of the behaviours you want.
I'm sure the same goes with humans. At the DNA level, I personally believe our minds are strongly influenced by the hidden codes in our genes. We can actively ignore these signals... but as you mentioned above, if all your genes combined like all kinds of food, dig in!
Very true! DNA is our OS to a certain degree. We can override it but it takes conscious effort.