If you're looking for an easy read, this is not it! If you're looking for a work of scientific depth expressed in language that shows you that the author is aware of the "meaning of it all", and is not just writing as a dry, scientific exercise, then this is the book for you!
The author takes the reader through the basics of genetics, through the enormity of the possibilities it offers, and into the origins of life. He also posits the idea that perhaps DNA and RNA are merely the current state of affairs, not necessarily always to remain with us. Like the stone age gave way to the iron age which gave way to the bronze age, maybe there were precursors to DNA and RNA, and perhaps there will be successors too.
The only problem I had was that, as a non life-sciences person, I had no previous knowledge of the subject at all, and it was only after I had read a simpler primer that I was able to appreciate what the author had to say. That's why I have given it four stars instead of five.
All in all, a very good read, absorbing and enthralling, with bits to chew over and think about, and bits to laugh at. Literary science at its best!