Genetics does not work that way.) Behavior straight out of genes, without social and environmental conditioning is bullshit. Behavior is product of training and acquired habits, guided by hard-wired instincts and emotions.
There might be some predispositions - mutations which introduce minor changes (there cannot be major ones - changes must be small and gradual enough for the organizm to cope with) into some locations, which affect sensitivity to certain chemical compound (hormones, neurotransmitters) or minor structural changes which affects metabolism, but all this could be easily compensated by behavioral patterns on a higher level.
Animals and people with sudden traumas leading to disability are doing this, but way too sophisticated, self-obsessed hipstes and couch potatoes cannot.