"Worm" is an engaging book about the beginning of genome sequencing, originating from the focused study of a type of nearly-microscopic, transparent worm. It is a chronicle of a historic research effort, and an insight into how research is conducted, rather than a technical discussion of biology. Andrew Brown assumes the reader has very little knowledge of genetics, and takes care to explain (in simple terms) key topics that are necessary to understand events and their importance to the narrative.
I would have liked there to be just a little more technical discussion in the book, but the author leaves numerous footnotes and sources pointing to further reading.