Thompson & Thompson Genetics in Medicine: With STUDENT CONSULT Online Access (GENETICS IN MEDICINE)

This is a great study guide for the American Board of Medical Genetics exam. It covers cytogenetics and molecular genetics in depth, and also discusses other important concepts such as Hardy-Weinberg Equilibrium, Population Genetics, Genomics, and single gene and complex inheritance.
I have not used the on-line access feature yet, but I have noticed a lot of improvements from the previous printed edition, including reorganized chapters, new/updated end-of-chapter questions, new statistics based on a more updated human gene count/information, and new sections on array comparative genomic hybridization. Overall, it would be essential to own this book if you're studying for the ABMG board exam, although I would also recommend supplementing your studies with other resouces to be more comprehensively prepared.

This is a quite comprehensive and general overview of medical genetics, with perhaps more focus on scientific research than clinical practice, although both are well represented.

However, this is a rapidly changing field of research, and some of the newest techniques (such as whole genome association studies) and most informative websites (such as SNPedia) that are insufficiently addressed in this edition will presumably get caught only in the (hopefully frequent) future editions.