When someone says “Genetic Engineering” our mind goes to a future (not-so-far-anymore) scenario where beings with modified physical traits are abundant but the truth is they have always been around us; we have been engineering life for thousands of years. Through selective breeding we strengthened useful traits in plants and animals for generations but we never really understood how it worked, until we discovered what DNA was. As soon as DNA was discovered scientists all around the world started working on techniques to manipulate it to manifest useful phenotypic traits in organisms.
Fast forward to today where we produce chemicals from engineered life, have genetically modified plant products that stay fresh longer, super muscled pigs for more meat, fast growing salmon, featherless chickens and see-through frogs. Not to forget glowing (florescent) zebra fish are available for as little as $10 at Walmart. Half a century ago this would have sounded like bizarre science fiction but it’s real now! All of this is very impressive but until recently the cost of gene editing was really high, it was really complicated, and took a long time to do. This has now changed with a revolutionary new technology called CRISPR (clustered regularly interspaced short palindromic repeats), try saying this tongue twister! Overnight the costs of gene editing have shrunk by 99%, instead of taking years it now takes a few weeks to conduct experiments, and basically anyone with a lab can do it.
CRISPR was discovered in bacteria, where scientists found that a protein called Cas9 was capable of taking RNA copies from bacterial DNA archives, able to find exact DNA match in foreign invaders in the bacteria and then able to cut that foreign invader DNA (go read the beautifully written paper called “Multiplex Genome Engineering Using CRISPR/Cas Systems” on http://science.sciencemag.org/content/339/6121/819 to learn more about CRISPR). Soon after it’s discovery scientists found out that CRISPR system was programmable. That you can put the Cas9 protein into any living cell, give it a copy of RNA for the DNA you want it to find and let it do it’s job of finding that exact DNA match and cutting it, voila! So CRISPR can manipulate live cells precisely to turn genes ON and OFF, that’s how big of a revolution it is!
In a short amount of time since CRISPR was disovered, scientists have been able to clear HIV virus from live animals using CRISPR (go read “In Vivo Excision of HIV-1 Provirus by saCas9 and Multiplex Single-Guide RNAs in Animal Models”), treat muscular dystrophy in mice (go read ” Muscle-specific CRISPR/Cas9 dystrophin gene editing ameliorates pathophysiology in a mouse model for Duchenne muscular dystrophy”) and trails are underway to treat cancer using CRISPR. Human trials for CRISPR cancer treatment were approved in mid-2016 in both US and China!
Things are picking up pace rather quickly as you can appreciate. So what about genetic diseases like Hemophilia, Huntington’s, Down Syndrome, or even less fatal genetic conditions like Color blindness? Over 3000 genetic diseases are caused by a single incorrect nucleotide base-pairing (SNPs) in human DNA. As I write this and you read this, scientists are working on a modified version of Cas9 (Cas9 2.0 if you will) that will be able to correct these SNPs, fixing the disease in the cell. In a decade or two we will be able to cure thousands of diseases forever in patients. But all CRISPR applications have one thing in common, they are limited to the individual and die with them! EXCEPT, if you use them on reproductive cells or very early embryos.
CRISPR can and probably WILL be used for much more (than just treating existing patients), the creation of modified humans, designer babies. The means to edit a human embryo already exist and it has already been attempted not once but twice (http://www.nature.com/news/chinese-scientists-genetically-modify-human-embryos-1.17378)! The researchers were only partially successful in doing so and said “Our results reveal serious obstacles to using the method in medical applications but we are working on solving them.” The way many people see CRISPR is like the computer in the 70s, there will be better CRIPSR tools just like there were better computers.
Regardless of YOUR personal take on genetic engineering, it will effect YOU because once you start editing genes in embryos and reproductive cells those genes can be passed down to future generations. Live births resulting from modified embryos could alter the gene pool of our species over generations. As soon as the first genetically modified kid is born, a door is opened that cannot be closed anymore.
It’ll start slow, “designer babies” will not be overly “designed”. It’s most likely that they will be created to treat a genetic disease running in a family. As the technology progresses and gets more refined, more and more people will argue that NOT using genetic modification is unethical because it condemns children to preventable suffering, or death and denies them the cure. Early on, vanity traits like skin color, eye color, hair color etc. will be left alone and diseases will be eliminated BUT as genetic modification becomes more accepted and more CRISPR technologies are developed, the temptations will grow. If you give your offspring immunity to Alzheimer, why not also give them an enhanced metabolism, why not add in a perfect eyesight, more muscular definition, maybe treat adult baldness……you name it.
Just like featherless chicken, see through-frogs, glowing fish sounded like utter science fiction with no basis in reality half a century ago, this all might seem improbable now. But just as those things are a part of the current reality, we are all but only a few decades away from developing designer babies and changing the fate of humanity forever. The debate over human embryo editing is sure to continue for some time, just as the research will. Gene-editing on human embryos using CRISPR is a revolutionary application no doubt, but could this also be a slippery slope towards eventually cherry-picking what future offspring would be like? The answer, most like, is a whopping YES.
— Arpit Sharma