It’s undeniable that the way you are initially is a result of your genetic inheritance and early experience.
OK. Well, here's my move: To begin with, one could argue -- and it seems a reasonable argument to me and sounder scientifically -- that while we are conditioned by our genetic inheritance and early experience, we are not determined by them. Since when do my experiences determine my subsequent behavior? They certainly influence it. Moreover, I don 't see that the notion of free will necessarily implies full and ultimate responsibility. My responsibility and my knowledge are both as finite as I am. My judgment is imperfect, and my choices may -- and often are -- flawed. Get real, professor.
(You may also know, contrary to popular opinion, that current science gives us no more reason to think that determinism is false than that determinism is true.)
Well, apparently Ian McEwan doesn't know that, given what he is quoted as saying in the final paragraph, that the "arguments [against free will] seem watertight." McEwan also says that "I take on full accountability for the little ship of my being, even if I do not have control of its course. It is this sense of being the possessor of a consciousness that makes us feel responsible for it.” But by his logic he isn't taking on anything. That's just the way he happens to feel, and he can't help feeling that way because he has been determined from the start to feel that way. You're either free -- to whatever extent -- or you're not.