Parts of it are superb. Other parts are needlessly redundant or an absolute waste of space. It could've been at least a quarter shorter without missing much.

Issacson gives too much airtime to bioethicists; in doing so he legitimizes them. Steven Pinker said it best when he told bioethicists to, "Get out of the way." Pinker elaborates further here.

Essentially, by perpetuating the meme that we should move slowly with biotech (lest we offend the bioconservatives) we are perpetuating the death and suffering of millions worldwide. Treating the human germline as holy ground is not only patently ridiculous, it is wildly immoral.

I genuinely do not understand how so many people (including the biotech innovators themselves) have been brainwashed with this meme. George Church is a notable exception.

All that being said, I thoroughly enjoyed the book and eagerly await his next work. Definitely a 5-star book, it's just irresponsible that he's mindlessly parroting a meme that is perpetuating death/suffering needlessly.