If you're already familiar with genetics you won't learn much new about the topic itself, but this isn't the goal of the book. It tells many small stories which happened along the lines of the progress in genetics. Starting of with Lamarck and Mendel you will discover lots of seldom told info-bits (which genetic disease probably turned Paganini into the virtuous violinist, how some mad russian scientist wanted to create humanzees at the beginning of the 20th century and, along many others, of the great race for the human genome between the HGP and Craig Venter).

All in all a nice book if you're interested anecdotes and the history of science.