We hate the thought of genetic influence like we hate the thought of chemical malfluence. Alone all by ourselves at the table of transcendence, the ambrosia of auto-encomium flows like the blood of the forbidden fruit after you just knocked over Adam's lemonade stand. I can't get drunk. I'm never scared or lonely or confused. Alcohol neither affects nor effects me, and faced with the rugged nature of my indefatigable bloodstream, sodium thiopental is nothing but an extra sprinkle of table salt on my matzo.
I'm neither here nor there. I see other people with different traits, but I refuse to believe in them because, if mere chemicals have any influence on them, then they would, by deduction, have a similar influence on me, me, mighty me, and that would suggest that I'm not a special snowflake and that I might actually die like everyone else who has died, which I prefer to believe is a sheer impossibility. To believe that anything beyond my control can affect my control would be audacious, unthinkable, because that would mean I'm just like the rest of them, mortal and listless, bereft of absolute power and unable to alter the totality of my environment at a whim. Any seeming chemical proclivity to design machinery or to throw punches is an illusion generated by the confluence of non-snowflake elements seeking to destroy my individuality, whose foundation rests upon the cycle of my belief in others' individualities, therefore I firmly cling to it, I cling to it like life itself, because in a way, it is life itself; it's all I believe in and all I know. Genes don't have predictable effects, alcohol doesn't have predictable effects, and further tests are needed to explain why most car accident victims who traverse windshields at speed do so only with injury.
...which is all very well and good, but even within the safety of the illusion, the conclusion that you're not a snowflake because of your shell's verifiable commonalities ignores the element of choice that went into selecting why you were here in the first place, and why you chose to express yourself in any given form. Fine, you can employ the universality of "your" selection to ascribe it to a beyond-you, but even so, that you is in all things, and even the most materialistic free will presupposes your own agency in selecting what types of sin will tempt and shape you, and/or how you will refine your rage or cunning for that eventual malebolge. In short, if you chose the steroidal handicap, backing out of it halfway through is akin to penciling down your score on Hole 7 when no one, not even your own caddy, is looking. Part of the drama is that many of the choices have already been made, and that there's only one person to blame for them.
Sure, it's all bullshit, but what else are you gonna believe in while you're here? Hobgoblins and dawkinses? Eloi dying peacefully in the shadow of the red shield? I didn't think so. You've got nothing left but you.