Genes are tiny pieces of DNA that carry traits which can be passed from parents to their children. One way to find a specific gene—one that causes disease, for example—is to discover a genetic "marker," a piece of DNA that sits very close to the gene. Markers come in different varieties and everyone has them. People who get sick have one form of the marker and people who don't get sick have another.
Studies the genes that cause hereditary diseases
Find out how this kid from Kansas grew up to be a gene hunter in Venezuela.
Follow Nancy in her search for a cure to Huntington's disease.
Track the traits that run in your family.
"Taking part in the struggle against hereditary diseases has given me purpose and direction, and perhaps the privilege of saving lives."