Which is used to make a linkage map for a group of organisms?

A linkage map is created using genetic markers, such as single nucleotide polymorphisms (SNPs) and microsatellites, to estimate the relative positions of genes on a chromosome. By analyzing the frequency of recombination between these markers during meiOSis, researchers can determine how closely linked different genes are. This information is then used to construct a map that illustrates the arrangement of genes within a group of organisms, aiding in the study of genetics and breeding programs.