|a gene with two or more alternative forms, producing readily identifiable variations in a particular character, used in studies of linkage, genetic mapping, and identification of the presence of other genes that are closely linked to, and therefore usually inherited with, it|
genetic marker n.
A gene phenotypically associated with a particular, easily identified trait and used to identify an individual or cell carrying that gene.
A gene or DNA sequence having a known location on a chromosome. Genetic markers associated with certain diseases can be used to determine whether an individual is at risk for developing an inherited disease.