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AN EXTRAORDINARY INITIATIVE to re-green the world by wealthy philanthropists. https://www.thetimes.co.uk/article/meet-the-knepp-group-the-billionaires-dedicated-to-rewilding-the-environment-dgqrmxl9w View in LinkedIn

SO ENDS this first weekend contemplating the (almost) universal genetic code. While this is the configuration of inheritance on this planet, it is unlikely that it should be the same signature of life on other planets, or form a basis for the search for other life forms. On Earth, it has been a lucky accident, driven by the local physical conditions and material constraints of the planet. More than likely, there are thousands of other solutions to the same basic challenge of encoding inheritance. View in LinkedIn

HIGHLY UNIFORM. “Understanding how this code originated and how it affects the molecular biology and evolution of life today are challenging problems, in part because it is so highly conserved — without variation to observe it is difficult to dissect the functional implications of different aspects of a character.” https://www.sciencedirect.com/science/article/pii/S0960982216309174 View in LinkedIn

CIPHER NOT A CODE. “The code is actually closer to a cipher than a code, and individual species do not have a unique genetic code to be cracked; indeed one of the interesting characteristics of the code is that nearly all life shares exactly the same one, once called the ‘universal genetic code’.” https://www.sciencedirect.com/science/article/pii/S0960982216309174 View in LinkedIn

COMMON BUNKUM. “We often hear in the scientific and even popular press that the ‘genetic code’ of some organism has been ‘cracked’ by genomics, which is of course total nonsense. The genetic code is not the nucleotide sequence of the genome, but rather the set of rules by which those nucleotides are translated into amino acids and by extension genes into proteins.“ https://www.sciencedirect.com/science/article/pii/S0960982216309174 View in LinkedIn

SHEER LUCK. “It is tempting to think that a system so central to life should be elegant, but of course that’s not how evolution works; the genetic code was not designed by clever scientists, but rather built through a series of contingencies.” https://www.sciencedirect.com/science/article/pii/S0960982216309174 View in LinkedIn

THE FOUR INTO TWENTY. “The genetic code is a concept that captured the imaginations and drove much of the research of the first molecular biologists; almost immediately after the description of the double helix some very elegant models for how 4 ‘letters’ of DNA could encode 20 letters of protein were proposed.” https://www.sciencedirect.com/science/article/pii/S0960982216309174 View in LinkedIn

OTHER PLAYERS. “Phylogenetic analysis of translation system components, in particular aminoacyl–tRNA synthetases, shows that, at a stage of evolution when the translation system had already attained high fidelity, the correspondence between amino acids and cognate codons was determined by recognition of amino acids by RNA molecules, i.e., proto-tRNAs.” http://www.annualreviews.org/doi/abs/10.1146/annurev-genet-120116-024713 View in LinkedIn

FIDELITY IS A BY-PRODUCT. “The structure of the standard genetic code is nonrandom and ensures high robustness of the code to mutational and translational errors. However, this error minimization is most likely a by-product of the primordial code expansion driven by the diversification of the repertoire of protein amino acids, rather than a direct result of selection.” http://www.annualreviews.org/doi/abs/10.1146/annurev-genet-120116-024713 View in LinkedIn

WHY IT IS UNIVERSAL. “The universality of the code likely results from the combination of a frozen accident, i.e., the deleterious effect of codon reassignment in the standard genetic code, and the inhibitory effect of changes in the code on horizontal gene transfer.” http://www.annualreviews.org/doi/abs/10.1146/annurev-genet-120116-024713 View in LinkedIn