Genetics is the study of variation in genes and heredity. The sub-disciplines of genetics include evolutionary genetics, epigenetics, population and conservation genetics among others. The field draws on the basic principles of trait inheritance and molecular inheritance. The emergence of gene editing and gene mapping tools has broadened the frontiers of genetics and facilitated the study of individual gene inheritance, expression and change on all stages of embryo growth. From theories to practical applications, all relevant topics in the field of genetics have been included in this book. It presents the complex subject of genetics in a comprehensive and easy to understand language. It will serve as a valuable reference guide for geneticists, academicians, researchers and students.