"Telltale Genes: Charting Human Disease" by Richard P. Lifton, MD, PhD

Why children resemble their parents has intrigued scientists for thousands of years. The discovery of DNA as the basis of heredity led to an explosive growth of knowledge about the human genome and allowed the identification of genes that predispose people to different diseases. The Human Genome Project aims to determine the entire 3 billion base pair sequence of DNA and ultimately identify all the genes, estimated between 60,000 and 100,000, that define humans.*

*The first draft of the human genome was published in 2001. Most researchers have revised their estimates of the number of genes in the human genome downward, many to as low as 30,000.