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BECOMING ESSENTIAL. "Surprisingly, new genes can quickly acquire essential roles in development. Chen et al., identified 59 genes that originated in the last ~35 MYs in Drosophila that evolved essential developmental functions. Silencing new genes can also have a critical effect on reproduction, even when the individual can complete development." https://lnkd.in/dvpUaYF View in LinkedIn

SYNGAMIC FUSION. "The counterpart of meiosis, the syngamic fusion of haploid cells to form diploids may have been advantageous to survive famine as well as providing greater resistance to the highly mutagenic environment that existed 1 Gy ago." https://lnkd.in/d8Qr_bk View in LinkedIn

ANCIENT GENOME EDITING. "What were the disadvantages of circular chromosomes that could have ensured the supremacy of an incipient eukaryote with linear chromosomes? It has been suggested that the answer lies in the first division of meiosis. Meiosis may have first evolved as a mechanism to correct polyploidy arising from genome segregation mistakes." https://lnkd.in/d8Qr_bk View in LinkedIn

SUCCESSFUL CIRCULAR DESIGN. "Before the linear chromosomes of eukaryotes emerged ∼1 Gy ago, circular chromosomes had been successfully used for 2 Gy and they continue to predominate in the most common organisms on this planet (eubacteria and archaea)." https://lnkd.in/d8Qr_bk View in LinkedIn

WHY CIRCULAR CHROMOSOMES? "Meiosis entails chromosome segregation, and thus it is important to consider the nature of the chromosomes involved given that most modern prokaryotes have circular genomes." http://cshperspectives.cshlp.org/content/6/3/a016154.full View in LinkedIn

EDITING EPIGENETICS. "Assuming some epigenetic defects are nevertheless transmitted to the next generation, sexual reproduction and outbreeding would be advantageous because they provide the opportunity for their removal at the next meiosis. Inbreeding would be disadvantageous, because it increases the probability that epigenetic defects would become homozygous and could no longer be removed by recombination." https://lnkd.in/dx9WaSq View in LinkedIn

EPIGENETIC REPROGRAMMING. "It is proposed that the absence of a functionally important methyl group in a promotor or operater region produces a recombinator or signal for the initiation of recombination. The formation of hybrid DNA in this region then allows the lost methyl groups to be replaced by maintenance methylase activity. The removal of epigenetic defects by recombination during meiosis therefore becomes an essential part of a reprogramming and rejuvenation process." http://europepmc.org/abstract/med/6400219 View in LinkedIn

CONFINED. "There is also evidence that recombination at meiosis is largely confined to structural genes or adjacent DNA." https://lnkd.in/dx9WaSq View in LinkedIn

EPIGENETICS. "Evidence is now available which strongly indicates that the control of gene activity in higher organisms depends in part on the pattern of cytosine methylation in DNA, and that this pattern is inherited through the activity of a maintenance methylase. Epigenetic defects may arise by the loss of methyl groups which the methylase is unable to replace in somatic and also germ line cells, if de novo methylation cannot occur." https://lnkd.in/dx9WaSq View in LinkedIn

BIOLOGICAL FUNCTIONS OF MEIOSIS #4. "Fourth, that it helps maintain the immortality of the germ line, possible by a process of rejuvenation involving the removal of faulty RNA and protein molecules, or by the elimination of defective meiocytes." https://lnkd.in/dx9WaSq View in LinkedIn