What is Recombination: Definition and 64 Discussions

Genetic recombination (also known as genetic reshuffling) is the exchange of genetic material between different organisms which leads to production of offspring with combinations of traits that differ from those found in either parent. In eukaryotes, genetic recombination during meiosis can lead to a novel set of genetic information that can be passed on from the parents to the offspring. Most recombination is naturally occurring.
During meiosis in eukaryotes, genetic recombination involves the pairing of homologous chromosomes. This may be followed by information transfer between the chromosomes. The information transfer may occur without physical exchange (a section of genetic material is copied from one chromosome to another, without the donating chromosome being changed) (see SDSA pathway in Figure); or by the breaking and rejoining of DNA strands, which forms new molecules of DNA (see DHJ pathway in Figure).
Recombination may also occur during mitosis in eukaryotes where it ordinarily involves the two sister chromosomes formed after chromosomal replication. In this case, new combinations of alleles are not produced since the sister chromosomes are usually identical. In meiosis and mitosis, recombination occurs between similar molecules of DNA (homologous sequences). In meiosis, non-sister homologous chromosomes pair with each other so that recombination characteristically occurs between non-sister homologues. In both meiotic and mitotic cells, recombination between homologous chromosomes is a common mechanism used in DNA repair.
Gene conversion - the process during which homologous sequences are made identical also falls under genetic recombination.
Genetic recombination and recombinational DNA repair also occurs in bacteria and archaea, which use asexual reproduction.
Recombination can be artificially induced in laboratory (in vitro) settings, producing recombinant DNA for purposes including vaccine development.
V(D)J recombination in organisms with an adaptive immune system is a type of site-specific genetic recombination that helps immune cells rapidly diversify to recognize and adapt to new pathogens.

View More On Wikipedia.org
Recent contents Top users
  1. O

    Laser question (non-molecular, bi-molecular and auger recombination)

    what do we mean by ... 1. non molecular recombination 2. bi-molecular recombination and 3. auger recombination of laser... please reply if u have the ans. thank u
  2. U

    Redshift at recombination

    Homework Statement We are to assume the recombination happens at redshift z_{rec} when the number density of photons n_{\gamma}(z_{rec}) capable of ionizing hydrogen is exactly equal to the number density of baryons n_{b}(z_{rec}) . Use the measured number density of baryons, the...
  3. M

    Reduced Mass Effect on Recombination Lines Explained

    Could someone explain to me what is the "reduced mass" effect on the recombination lines? My teacher told me that would explain why the wavelength I calculated seems a little bit off with the experimental result. I don't seems to find the information anywhere...Thank you in advance.
  4. T

    Era of recombination - temperature variant

    Homework Statement When radiatio was first emmited 300,000 years after the big bang during the so-called era of recombination, it was in the visible region of the spectrum. What does this data tell scientist about the temperature variant of the early universe Homework Equations The...
  5. 2

    Baryon density of the universe at recombination epoch

    Hi I am just looking for the formula to calculate the baryon density of the universe at the recombination epoch. Is it a case of adding the average density of matter + radiation? but this does not take into account the recombination epoch (z=1200). I do not have a background in physics...
  6. V

    How Do Recombination and Drift Current Influence Diode Operation?

    1.what is the link between recombination and drift current for the current flow process in a diode(1.for unbiased condition 2. for biased condition) at equilibrium. i have the feeling that both are same as i read that diffusion compensates drift at some places and at other places, diffusion...
  7. B

    Thermalization and recombination when donors are present

    Ok, let's say you have n-type impurities in a semiconductor. So there is an equilibrium number of electrons in the conduction and impurity bands given by the temperature and the typical semiconductor statistics. Now, you excite electrons from the valence to the conduction band. Here are my...
  8. LydiaAC

    Generation and recombination in stationary state

    I know that in a semiconductor in thermal equilibrium generation and recombination are equivalent. This is obvious from continuity equation since in thermal equilibrium there is no time derivatives nor spatial gradients. However, I have read that in "stationary state" generation and...
  9. A

    Recombination of plasma ions and electrons

    If plasma is a collection of positive ions and electrons, why don't they recombine together and become neutral?
  10. P

    How to identify the ratio of the cross sectio of capture and recombination

    Sometimes we need to know the ratio of the capture section and recocmbination cross section of the electron or hole. for example, to identify the mechanism of phosphors, it's very important to know the ratio to analyze the process of luminescence. The question is how we identify the ratio, from...
  11. A

    BJT base recombination current

    I thought that the base recombination current (say in a pnp bjt) was the current caused by the electrons that come up the base wire to compensate the loss of free electrons from the recombination process in the base. But recently I read that this are actually two different currents that sum up...
  12. C

    Drawing a genetic map (recombination)

    We discovered that in the fungus Sordaria fimicola, a gene caused the fungus to produce normal black or mutant tan colored ascospores. Observations of crosses between normal and mutant fungi showed that 56% of the asci produced by these hybrid fungi are recombinant. This translated to a 28%...
  13. S

    Was Cosmic Recombination Caused by Charge Attraction or Positron Infusion?

    There are many recombination processes:http://en.wikipedia.org/wiki/Recombination but specifically in cosmology the process deals with the Electron attaching itself around Nuclei to form atomic structure's? Previous to this moment, electrons were spread out at vast distances through space...
  14. Monique

    Inducing somatic recombination

    Again such a nicely orchistrated technique. Used, for instance, when you’d like to look at a mutation which is lethal to an embryo: you’ll have to induce the mutation later in life in order to actually observe the effects. What to do? Insert a gene that induces mitotic crossing-over and place...
Back
Top