<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (September 2013) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (September 2013) (Learn how and when to remove this template message) </Td> </Tr> <P> Gene mapping describes the methods used to identify the locus of a gene and the distances between genes . </P> <P> The essence of all genome mapping is to place a collection of molecular markers onto their respective positions on the genome . Molecular markers come in all forms . Genes can be viewed as one special type of genetic markers in the construction of genome maps, and mapped the same way as any other markers . </P>

Physical location of a gene on a chromosome is called