This book is designed to provide the medical student with everything needed to ace step 1 board questions concerning medical genetics. This subject is handled in a step-wise, simple-to-understand fashion, from the analysis of pedigrees and their complications to the mechanisms which cause abnormalities of chromosome number and shape. The issues of prenatal genetic counseling on recurrence risk using Punnett squares and population analysis within affected families are explained, as well as means of direct and indirect diagnosis of a single gene and mitochondrial defects. The Hardy-Weinberg equation is derived and its use is demonstrated in a simple, understandable sequence of steps. Each chapter is followed by open-ended practice questions which are designed to help students work through the logic and mathematical calculations to answer any and all board questions in the field and calm their anxiety on the subject so that they will be able to reason under exam pressure. Finally, the book concludes with step-wise solutions to all the practice questions, so that students can check their work and gain the confidence they need to excel.