genetic markers

Definition of genetic marker
National Cancer Institute

genetic marker

(jeh-NEH-tik MAR-ker)
A specific sequence of DNA at a known location on a chromosome. There are many genetic markers on each chromosome. Genetic markers and genes that are close to each other on a chromosome are usually inherited (passed from parent to child) together. This may help researchers find a gene near a marker that may cause a certain disease or trait within a family. Examples of genetic markers are single polymorphism nucleotides (SNPs) and microsatellites.

Source: NCI Dictionary of Cancer Terms