Cetainly we are all greatly influenced by our genetics and by nature. But perhaps we are also influenced to a large degree by our enviornment and by what happens in our life. I'm not saying that we are all unique, even though genetically at least we are, nor am I saying that we all have "free will". I just think it's narrow minded to think that we are products of instict alone.
It can be proven scientifically that much of human behavior, more than anyone had ever predicted, is directed by DNA, but it is also a fact that our genes are programmed to adapt to our enviornment and change over time in response to the events in our lives.
This isn't really "free will", but it does suggest that not everything we do is not base soley on instict.