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GENE TURNOVER IN MAN. "Next-generation sequencing and microarrays have identified over 1200 partial and 600 complete gene duplications/deletions in 179 individual human genomes relative to the reference." https://lnkd.in/dvpUaYF View in LinkedIn

NEW GENES IN VERTEBRATES. "The rates of new gene origination are variable in different evolutionary stages of vertebrates, although 25–30 genes generated by DNA-based and RNA-based duplication and de novo arise per MY. Interestingly, this rate is much higher on branches closer to human (65 new genes per MYs in the human lineage alone).” https://lnkd.in/dvpUaYF View in LinkedIn

NEW GENES IN FRUIT FLIES. "Zhou et al., computationally estimated new gene origination rates in the D. melanogaster subgroup via DNA-based duplication, retroposition, de novo origination and gene recombination to be 5–11 new genes per million years, and found different rates for the four mechanism." https://lnkd.in/dvpUaYF View in LinkedIn

FOUR MECHANISMS. "New genes generated by four main mechanisms have been examined: DNA-based duplication, retroposition, de novo origination and exon/domain shuffling. There have been no reports of new gene origination rates for mechanisms other than DNA-based duplication, RNA-based duplication, de novo origination, and gene recombination. Thus the rates of new gene origination we highlight should be viewed as serious underestimates." https://lnkd.in/dvpUaYF View in LinkedIn

RADICAL RENOVATION. "And while these mechanisms may generate the initial gene structures, many new structures (in a large variety of taxa) undergo radical structural renovation to change exon-intron structure, or even recruit new or existing coding sequence into the new locus." https://lnkd.in/dvpUaYF View in LinkedIn

EXCEPTIONS. "This argument ignores systems like the bacterial XerD/C resolution machinery, which efficiently cuts dimeric circular chromosomes at specific dif sites. A similar system could have been used to resolve dimeric circles in the meiosis of early eukaryotes." https://lnkd.in/d8Qr_bk View in LinkedIn

SO ENDS this curated glimpse into gene life cycles. Pseudogenes, retrogenes, chimeric genes, gene recruitment and modification, gene silencing, and vertical gene transfer can occur at florid rates: there is nothing static in the world of genes. New metabolic pathways, new gene regulatory systems and genetic rewiring all occur continuously on biological timeframes, and all appear to be subject to, and shaped by, the great hand of natural selection by selective survival. View in LinkedIn

LINEAR PLUSES. "In the reductional division of meiosis, the homologous chromosomes are held together by their chiasmata where recombination has generated a crossover between homologous chromatids. A single meiotic crossover (or any uneven number of crossovers) generates a dicentric circle, which will lead to non-disjunction of the homologs. As this problem is circumvented with linear chromosomes, linearization may have provided a selective advantage." https://lnkd.in/d8Qr_bk View in LinkedIn

POTENT DRIVERS. "New genes now appear to be potent drivers of phenotypic evolution and the genetic control of important biological processes, and show that organismal development and organ development have evolved species-specific and lineage-specific components." https://lnkd.in/dvpUaYF View in LinkedIn

PLOIDY SWITCHES. "It was argued that switching between diploid and haploid states poses a problem for organisms with circular chromosomes." https://lnkd.in/d8Qr_bk View in LinkedIn