This book is the most condensed, accessible discussion of genetic manipulation techniques and methods around. Armed with this, one can move on and understand any other text in the area.
Very good for appreciating the field and understanding its fundamentals. For Instance doesn't just explain what chromosomes are, it explains why they exist
This book was a recommended text for the cell and Molecular Biology module on my Masters degree. It is very informative and a good start in understanding genes and genomes.