Navigation Links
Chromosomal crossover


Chromosomal crossover 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 to the different end piece. If they break at the same place or locus in the sequence of base pairs, the result is an exchange of genes. This outcome is the normal way for crossover to occur. If they break at slightly different loci, the result can be a duplication of genes on one chromosome and a deletion of these on the other. If they break and rejoin on opposite sides of the centromere, the result can be one chromosome being lost during cell division. If homologous chromosome are not perfectly aligned an unequal crossover may occur, an unequal crossover can create duplicate genes.

Any pair of homologous chromosomes may be expected to cross over three or four times during meiosis. This aids evolution by increasing independent assortment, and reducing the genetic linkage between genes on the same chromosome.

The physical basis of crossing over was first demonstrated by Harriet Creighton and Barbara McClintock in 1931.


See also


'"/>


(Date:4/3/2017)...  Data captured by IsoCode, IsoPlexis Corporation,s ... statistically significant association between the potency of ... objective response of cancer patients post-treatment. The ... cancer patients will respond to CAR-T cell ... to improve both pre-infusion potency testing and cell ...
(Date:3/29/2017)... -- higi, the health IT company that operates the largest ... , today announced a Series B investment from BlueCross ... new investment and acquisition accelerates higi,s strategy to create ... health activities through the collection and workflow integration of ... and secures data today on behalf of over 36 ...
(Date:3/24/2017)... -- Research and Markets has announced the addition of ... - Industry Forecast to 2025" report to their offering. ... The Global Biometric Vehicle ... around 15.1% over the next decade to reach approximately $1,580 million ... estimates and forecasts for all the given segments on global as ...
Breaking Biology News(10 mins):
Other biology definition