Geneticists, or genetic scientists, study heredity. Heredity is the process by which certain characteristics of an organism are handed down from parent to offspring. Geneticists study plants and animals, including humans. Geneticists work in three broad fields: biology, medicine, and agriculture. They attempt to increase knowledge about biology in order to understand and cure genetic diseases. Also, they counsel families at risk for genetic diseases or disorders. Geneticists breed new crop plants and livestock that are disease resistant or have other desirable properties. The rapidly growing biotechnology field uses genetics to produce everything from medicines to microchips. Sensitive genetic tests are being increasingly used in criminal cases to identify persons. At the turn of the twenty-first century, geneticists are involved in very important work known as the Human Genome Project. This international research program aims to construct detailed maps of the human genome, determine the complete sequence of...