Wow dat title ^ I'm hilarious. Honestly like why am I so funny? People ask me all the time...
Okay, so this article talks about variation that occurs before and after mitosis and meiotic recombination. First, what is meiotic recombination? Meiotic recombination is one of the defining events in the formation of eggs and sperm. It is a process in which DNA is exchanged between "partner" chromosomes. If the process is distrubed, chromosomes often go astray during meiotic division, resulting in eggs or sperm with too many or too few chromosomes. In humans, the resulting embryos are almost always abnormal and are a major source of miscarriages or congenital birth defects, such as Down syndrome.
Meiotic recombination, crossovers (exchanges of genetic material between homologous chromosomes. One of the final phases of genetic recombination, which occurs during prophase I of meiosis in a process called synapsis), and gene conversions (process by which DNA sequence information is transferred from one DNA helix (remainging unchanged) to another DNA helix, whose sequence is altered; one way a gene may be mutated) all affect variation and are therefore important from an evolutionary standpoint. Crossovers increase genetic diversity by redistributing existing variation and gene converstions alter the frequency of alleles.
A group of researches conducted a series of experiments in which they sequenced Arabidopsis Landsberg erecta (Ler) and two sets of all four meiotic products from a Columbia (Col)/Ler hybrid to try and find the genome-wide variation. This would also help them find the meiotic recombination at the nucleotide resolution.
Their results showed many single nucleotide polymorphisms (SNPs) which are DNA sequence variations that occur when a single nucleotide in the genome differs between members of a biological species or paired chromosomes in an individual. They also found many different sized insertions and deletions, which matched the other SNPs throughout the genome. Using a mutant, they discovered that two sets of four meiotic products were produced. They were then analyzed by sequencing in a nonfungal species.
A total of eighteen crossovers and four gene conversions revealed that Arabidopsis gene conversions are probably fewer, and have shorter tracts, than those in yeast.
In conclusion, meiotic recombination and chromosome assortment dramatically redistributed genome variations in cells that undergo meiosis. This plays a hand in population diversity! It presents a quick way to generate copy-number variation of sequences whose chromosomes are positioned differently in both Col and Ler.
Okay, so this article talks about variation that occurs before and after mitosis and meiotic recombination. First, what is meiotic recombination? Meiotic recombination is one of the defining events in the formation of eggs and sperm. It is a process in which DNA is exchanged between "partner" chromosomes. If the process is distrubed, chromosomes often go astray during meiotic division, resulting in eggs or sperm with too many or too few chromosomes. In humans, the resulting embryos are almost always abnormal and are a major source of miscarriages or congenital birth defects, such as Down syndrome.
This image displays the two methods used in meiotic recombination that I have described below.
Meiotic recombination, crossovers (exchanges of genetic material between homologous chromosomes. One of the final phases of genetic recombination, which occurs during prophase I of meiosis in a process called synapsis), and gene conversions (process by which DNA sequence information is transferred from one DNA helix (remainging unchanged) to another DNA helix, whose sequence is altered; one way a gene may be mutated) all affect variation and are therefore important from an evolutionary standpoint. Crossovers increase genetic diversity by redistributing existing variation and gene converstions alter the frequency of alleles.
A group of researches conducted a series of experiments in which they sequenced Arabidopsis Landsberg erecta (Ler) and two sets of all four meiotic products from a Columbia (Col)/Ler hybrid to try and find the genome-wide variation. This would also help them find the meiotic recombination at the nucleotide resolution.
Their results showed many single nucleotide polymorphisms (SNPs) which are DNA sequence variations that occur when a single nucleotide in the genome differs between members of a biological species or paired chromosomes in an individual. They also found many different sized insertions and deletions, which matched the other SNPs throughout the genome. Using a mutant, they discovered that two sets of four meiotic products were produced. They were then analyzed by sequencing in a nonfungal species.
A total of eighteen crossovers and four gene conversions revealed that Arabidopsis gene conversions are probably fewer, and have shorter tracts, than those in yeast.
In conclusion, meiotic recombination and chromosome assortment dramatically redistributed genome variations in cells that undergo meiosis. This plays a hand in population diversity! It presents a quick way to generate copy-number variation of sequences whose chromosomes are positioned differently in both Col and Ler.
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