This book unravels the mysteries surrounding susceptibility, pathogenesis, presenting features, clinical course, pharmacokinetics, therapeutic response and preventive aspects of illness. Explains variations, improves diagnosis, identifies subjects of illness, explores areas of pharmacotherapy, predicts prognosis, assists counselling and implements primary prevention as well as alleviates the anxiety of care providers and givers. Contains 5 chapters namely, Structure of Chromosomes, DNA Replication, Transcription, Gene Expression and Regulation, Applied Genetics along with Multiple Choice Questions and Index at the end. The entire text has been presented in a concise and lucid manner. 1. Structure of Chromosomes, 2. DNA Replication, 3. Transcription, 4. Gene Expression and Regulation, 5. Applied Genetics, 6. Multiple Choice Questions.