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FRAGMENT FROM NATURE continues from last weekend to this weekend’s conclusion of the fragment on gene life cycles. In biological time, genes are dynamic entities, being born and dying, being borrowed and shared. In one viewpoint, genes are the currency of life, the most important asset that is built up over time. The accumulation of more complex biological information on planet earth has been a steady process. See how this came about. View in LinkedIn

METABOLISM EXPANSION. "New genes can generate new biochemical pathways and products if they are enzymes or become enzymes." https://lnkd.in/dvpUaYF View in LinkedIn

PATH TO FIXATION. "Duplicate genes are most often inactivated and become pseudogenes. This classic model assumes that the new gene is functional upon duplication and that the new gene subsequently acquires mutations that provide a novel beneficial function. The novel function is then preserved in the genome by natural selection." https://lnkd.in/dvpUaYF View in LinkedIn

NEW GENE FORCES. "Evolutionary forces such as natural selection and genetic drift operate on both facets of new gene evolution: the fixation of new gene loci and their acquisition of a beneficial function." https://lnkd.in/dvpUaYF View in LinkedIn

NEW GENES IN RICE. "Over 1000 retrogenes were identified in the rice genome, 380 of which evolved chimeric gene structures by recruiting previously existing genes into their gene structures. https://lnkd.in/dvpUaYF View in LinkedIn

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