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Radiation Hybrid Mapping

Nucleic Acids Structure and Mapping

  1. William R. Newell

Published Online: 15 SEP 2006

DOI: 10.1002/9780470027318.a1425

Encyclopedia of Analytical Chemistry

Encyclopedia of Analytical Chemistry

How to Cite

Newell, W. R. 2006. Radiation Hybrid Mapping. Encyclopedia of Analytical Chemistry. .

Author Information

  1. Aventis Cambridge Genomics Center, Cambridge, USA

Publication History

  1. Published Online: 15 SEP 2006


Radiation hybrid (RH) mapping is a convenient and widely used method for rapidly locating new DNA sequences on genomes in relation to other DNA markers. The aim of the technique is to determine the correct order and relative distances between a set of markers, or to locate a new marker to its most likely location on a genome. We review the history of the technique, its current status, and the main analytical techniques used to generate maps from raw data. The physical processes and assumptions underlying the technique are examined. These processes are used to derive models from which the required information, location of markers with respect to each other on a linear map of DNA, is obtained by a variety of computational means. The RH technique has proved indispensable in mapping the human genome, since, unlike genetic mapping, the conditions under which panels are made is completely under experimental control, so mapping at any degree of resolution is possible. The other major advantage of RH mapping over genetic mapping is that markers need not be polymorphic; it is presence or absence of a marker that is detected, not type. It has therefore been used to map the large numbers of expressed sequence tags that have been generated as part of the human genome project (HGP). This has given rise to the first human gene map and subsequent updates, so that currently 40 000 genes have been assigned locations on the human genome.