Mapping

Genetic maps contain very important information and are used to help find the genes that can cause, or change the risk of developing, genetic diseases. For most diseases, the gene is not yet known and could be any one of the 30,000 to 70,000 genes that exist in the human genome. Since the disease gene is not known, its location is also not known. However, if the general location could be determined, then it would be much easier to figure out which of the genes near that location are the actual disease genes.

Genetic maps are very important for "disease-gene discovery," as they provide the reference locations for locating the disease gene. Finding the disease genes without a genetic map would be like trying to find a town by driving down a road without any mile markers or exit signs. There would be no clues as to where you are. The maps make it much easier to "navi-gate" the chromosomes.