Chromosomal landing is a genetic technique used to identify and isolate clones in a genetic library. Chromosomal landing reduces the problem of analyzing large, and/or highly repetitive genomes by minimizing the need for chromosome walking.
It is based on the principle that the expected average between-
marker distance
Distance is a numerical or occasionally qualitative measurement of how far apart objects or points are. In physics or everyday usage, distance may refer to a physical length or an estimation based on other criteria (e.g. "two counties over"). ...
s can be smaller than the average insert length of a clone library containing the gene of interest.
From the abstract of :
:The strategy of
chromosome walking
Primer walking is a technique used to clone a gene (e.g., disease gene) from its known closest markers (e.g., known gene). As a result, it is employed in cloning and sequencing efforts in plants, fungi, and mammals with minor alterations. This te ...
is based on the assumption that it is difficult and time consuming to find DNA markers that are physically close to a gene of interest. Recent technological developments invalidate this assumption for many species. As a result, the mapping paradigm has now changed such that one first isolates one or more DNA marker(s) at a physical distance from the targeted gene that is less than the average insert size of the genomic library being used for clone isolation. The DNA marker is then used to
screen
Screen or Screens may refer to:
Arts
* Screen printing (also called ''silkscreening''), a method of printing
* Big screen, a nickname associated with the motion picture industry
* Split screen (filmmaking), a film composition paradigm in which mul ...
the library and isolate (or 'land' on) the clone containing the gene, without any need for chromosome walking and its associated problems. Chromosome landing, together with the technology that has made it possible, is likely to become the main strategy by which
map-based cloning is applied to isolate both major genes and genes underlying
quantitative traits
Quantitative may refer to:
* Quantitative research, scientific investigation of quantitative properties
* Quantitative analysis (disambiguation)
* Quantitative verse, a metrical system in poetry
* Statistics, also known as quantitative analysis ...
in
plant
Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclu ...
species.
See also
*
Primer walking
Primer walking is a technique used to clone a gene (e.g., disease gene) from its known closest markers (e.g., known gene). As a result, it is employed in cloning and sequencing efforts in plants, fungi, and mammals with minor alterations. This te ...
References
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Molecular biology
Genetic engineering