As every schoolchild knows, just about all the molecules employed in living systems on this planet come in two forms. And these forms are mirror images of each other. [1] For example, all amino acids come in the so-called L Form, with their D form opposites almost unknown. And this is true from the simplest unicellular organisms right up to the highest form of life known, which is of course cats. (The situation with sugars is opposite; the D forms predominate)
Why this has occurred is not known. But it is a fact, which has several consequences, one of which is that all our medicines and drugs are finely tuned to the molecular situation as it is today, and has been for thousands of millions of years. So what happens if someone engineers organisms which are the exact opposite: they have D amino acids and L sugars? The result could be beyond catastrophic. It could result in pandemics of superorganisms which might wipe out not just humanity but also many of the organisms upon which we depend for our food. So we have two articles today, one by William Hunter of the Mail and one by Mark Lorch of the Conversation, Because we at LSS think that you our readers-parents, grandparents, citizens, be whomsoever ye may-need to take this one very seriously indeed.
And our thoughts? At first we dismissed it, idly thinking that “stereo-opposite” molecules could never function in human tissues. The we recalled the Thalidomide affair, where one mirror form had beneficial effects, and the other was highly toxic. Yes it functioned, alright-and with what awful consequences! Our second thought was that there is no shortage of malevolent actors, such as criminals, terrorists, or dictators of countries large and small ,who would hesitate to deploy superweapons of this sort, if they believed it would increase their power by one millimetre. We doubt that bans attempted by the intelligent and good willed(as advocated by the authors of this article) will have much effect. The only hope is research programmes to try to come up with antidotes. It seems we have about ten years.
[1]https://en.wikipedia.org/wiki/Chirality_(chemistry)
#chiral molecules #stereoisomer #enantiomer #thalidomide #microbiology # biochemistry #pandemic
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