Genes that are located close together on the same chromosome. Linked genes will not undergo independent assortment during gamete formation, constituting an exception to the law of independent assortment. Crossing-over will disrupt the linkage of two genes on the same chromosome if they are far enough apart.

linked markers   Genes or markers that show linkage q.v..

any pair of genes that tend to be transmitted together; "the genes of Drosophila fall into four linkage groups"