It has been suggested that this article or section be merged with Physical Map, but this suggestion is disputed. (Discuss)

A genetic map is a chromosome map of a species or experimental population that shows the position of its known genes and/or markers relative to each other, rather than as specific physical points on each chromosome. Wikipedia does not have an article with this exact name. ... Figure 1: Chromosome. ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... Genetic markers are DNA sequences that can be identified by a simple assay, allowing the presence or absence of neighbouring stretches of the genome to be inferred. ...

A genetic map is a map based on the frequencies of recombination between markers during crossover of homologous chromosomes. The greater the frequency of recombination (segregation) between two genetic markers, the farther apart they are assumed to be. Conversely, the higher the frequency of association between the markers, the smaller the physical distance between them. Historically, the markers originally used were detectable phenotypes (enzyme production, eye color) derived from coding DNA sequences; eventually, confirmed or assumed noncoding DNA sequences such as microsatellites or those generating RFLPs have been used. Recombination usually denotes a genetic event that occurs during the formation of sperm and egg cells (especially in areas of study of biology topics). ... Thomas Hunt Morgans illustration of crossing over (1916) Homologous Recombination is the process by which two chromosomes, paired up during prophase I of meiosis, exchange some distal portion of their DNA. Crossover occurs when two chromosomes, normally two homologous instances of the same chromosome, break and then reconnect but... Two chromosomes are said to be homologous when they have the same alleles at the same positions (loci) for all the genes they contain, besides being of the same length. ... The phenotype of an individual organism is either its total physical appearance and constitution or a specific manifestation of a trait, such as size, eye color, or behavior that varies between individuals. ... In genetics, noncoding DNA describes DNA which does not contain instructions for making proteins (or other cell products such as RNAs). ... A microsatellite is a short, noncoding DNA sequence (a Tandemly Repetitive DNA sequence) that is repeated many times within the genome of an organism. ... In molecular biology, the term restriction fragment length polymorphism (or RFLP) is used in two related contexts: as a characteristic of DNA molecules (arising from their differing nucleotide sequences) by which they may be distinguished, and as the laboratory technique which uses this characteristic to compare DNA molecules. ...

Genetic maps help researchers to locate other markers, such as other genes by testing for genetic linkage of the already known markers.

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