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GENE CONVERSION. "During meiosis, crossover recombination results from the pairing of homologous chromosomes and the formation of DNA double-strand breaks (DSBs), followed by synapsis, a process in which homologues become tightly paired along their length involving a protein structure known as the synaptonemal complex. DSBs are then repaired as either crossovers (hereafter ‘COs’), resulting in the exchange of large chromatid segments, or gene-conversion events." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

SCENARIO 2b. "In a variant of this scenario, early syngamy evolved as a result of ‘manipulation’ by selfish elements (plasmids, transposons) to promote their horizontal transmission." WOW. https://lnkd.in/e2tp_G5 View in LinkedIn

SCENARIO 2. "Proto-meiosis evolved in response to the fusion of two haploid cells (“syngamy”), as in standard modern eukaryotic sexual life cycles. Syngamy may have been favoured because it allows recessive deleterious mutations to be masked in diploids." https://lnkd.in/e2tp_G5 View in LinkedIn

SCENARIO 1. "Diploidy accidentally occurred by replication of the nuclear genome without subsequent cell division (“endoreplication”), and that returning to haploidy was selected for to correct this. Because either haploidy or higher ploidy levels may be favoured in different ecological situations, a variant of this scenario is that a proto-meiosis–endoreplication cycle evolved to switch between ploidy levels." https://lnkd.in/e2tp_G5 View in LinkedIn

EARLY EVENT. "A form of reductional cell division (a.k.a ‘proto-meiosis’) probably evolved in early asexual unicellular eukaryotes." https://lnkd.in/e2tp_G5 View in LinkedIn

SINGLE EVOLUTIONARY EVENT. "Meiosis is one of the ‘major innovations’ of eukaryotic life that evolved before their subsequent radiation over one billion years ago. Extant eukaryotes share a set of genes specifically associated with meiosis, implying that meiosis evolved only once before their last common ancestor." (Brilliant review). http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

EVOLUTION OF MEIOSIS. "The origin of meiosis through gradual steps is among the most intriguing evolutionary enigmas." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

CARTOON PICTURE. "In evolutionary biology studies, meiosis is also often simplified and represented by random assortment of chromosomes and recombination maps expressing the probability of recombination events between ordered loci, with little attention to the molecular and cellular details." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

EVOLUTIONARY SIGNIFICANCE. "Mechanistic studies of meiosis have been carried out in different fields, such as cell biology, genetics and epigenetics, encompassing a wide range of eukaryotes. However, these studies rarely focus on the evolutionary significance of meiotic mechanisms, rather mentioning them in passing and often in a simplified manner." http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf View in LinkedIn

KEY TO MEIOSIS SUCCESS. "This genetic reshuffling reduces genetic associations within and between loci and is thought to be the basis of the success of sexual reproduction." https://lnkd.in/e2tp_G5 View in LinkedIn