Banner by Daniel Walsh
Super Kids: the Future of Gene Editing?
by Carson Clark
It’s 2085, and David is two minutes old. Eight months earlier, his mother and father were worried for David’s life when their doctor informed them that their baby showed three copies of chromosome 3, essentially a death sentence. Luckily, the doctor explained that advances in genetic engineering allowed for the safe removal of the extra chromosome, and now newborn David sat happily in the arms of his mother.
Much before the development of modern genetics, the first instance of genetic manipulation has its origins around 10,000 B.C. when ancient farmers selectively bred crops with specific qualities to increase yield. These farmers selected different combinations of wild grasses to breed the precursors of modern staples like wheat and rice (http://www.sciencegroup.org.uk/ifgene/history.htm). Genetic engineering has come quite a ways since those early examples of exploiting genetics.
David is five months old. His mom smiles at his sleeping face. She remembers her doctor coming in after David’s first treatment, his face bearing bad news. He explained that David’s prenatal tests also showed trisomy 21 -- Down Syndrome. It wasn’t too late to alter this, the doctor explained. She and her husband couldn’t sleep for the next week. She still gets scolded by her mother: “How could you change something so important about him?!” She puts another blanket on sleeping David, wondering if she made the right decision.
Modern genetic engineering primarily uses a gene-editing technology called CRISPR-Cas9. Pioneered in 2012, CRISPR gene-editing involves the use of a guide-RNA, which is simply a molecule researchers create that binds to a specific portion of DNA. Once the guide-RNA binds to its specific portion of DNA, the guide RNA recruits a protein called Cas9, which binds to the DNA and unwinds it. This allows the RNA to bind to the newly opened DNA, and then Cas9 snips the DNA. The DNA now has to be repaired, and this can be done by disabling the gene, fixing the gene, or (of most interest to researchers) inserting a new gene into the DNA (https://www.sciencenewsforstudents.org/article/explainer-how-crispr-works). Basically, researchers can manipulate what cell machinery are active or inactive to influence how the DNA cut gets repaired, and therefore, researchers can selectively insert new genes into someone’s genome.
According to Beth Mole, writer at Nature.com, researchers are currently working on ways to silence the effects of Down syndrome with genetic modifications (http://www.nature.com/news/researchers-turn-off-down-s-syndrome-genes-1.13406). The strategy utilizes the gene XIST, the X-inactivation gene, which normally functions in females to silence one of her two X chromosomes. XIST produces molecules that act as a blanket of sorts, coating the entire surface of the chromosome and disallowing any expression from genes on that particular chromosome. Therefore, when the XIST gene is added via CRISPR-Cas9 to one of the extra chromosome-21’s in someone with Down Syndrome, the team of researchers think that they can silence that chromosome completely, and that a child with such a modification would develop normally. This technology could be applied to treat individuals suffering from any trisomy, not just those with Down Syndrome.
David is seven years old. He likes to race his classmates at school, and his mom recently signed him up for a club track league. At his first race, David wins the 100-meter dash in a time of 8.87 seconds; in 2009 Usain Bolt held the world record with 9.58, a time that would be laughably slow today.
While we might have some time before we decide whether to create super-athletes, the genetic possibility exists. In “Clinical Genetics in Nursing Practice,” author Felissa Lashley writes about a mutation in the gene that encodes ɑ-actinin-3 (https://books.google.com/books?id=chieefSNpwEC&pg=PA516&lpg=PA516&dq=are+superathletes+possible+in+the+future+genetics&source=bl&ots=UOfU28Vqyw&sig=tzvyklijrGBZiQlgXLCfBd8icAA&hl=en&sa=X&ved=0ahUKEwivjfD2q5vXAhUEMSYKHcvQCvsQ6AEIKzAA#v=onepage&q=are%20superathletes%20possible%20in%20the%20future%20genetics&f=false). This protein subunit is involved in generating muscle force through contraction of muscle fibers, and has been found to increase athletic performance. Lashley further argues that “using genotyping to select to select athletes based on possession of identified favorable genetic polymorphisms and discouraging others has serious ethical and societal implications.”
As supported by recent surveys, the public’s opinion might already be swaying in favor of the genetic modifications and creation of this “super-athlete” class. In 2009, New York University School of Medicine released a study that revealed “10 percent of parents surveyed would approve of genetic testing to ensure their child was athletic.” Just five years later, 26 percent of 1,001 surveyed Americans said that it would be a good thing if “prospective parents can alter the DNA of their children to produce smarter, healthier or more athletic offspring.” (https://theconversation.com/genetically-engineered-athletes-could-be-heading-this-way-soon-42166)
David is 14. He will start college in a few weeks. Most of his classmates will be around his age. He is a gifted student in math. He could out-compute his father, a mathematician himself, by the time he was 10. His high school offered advanced calculus and theoretical math classes, and in college he will study mathematical theories that were nonexistent 50 years ago--before the advent of genetic engineering.
Genetic engineering is becoming a hotly contested area of research as the field grows larger and more powerful. As gene therapies are currently being developed and used to fight diseases like respiratory and immunodeficiency conditions, the possibility of using genetic engineering for aesthetic and athletic purposes looms in the near future. As such, it is important for us as a society to have the difficult conversations now, considering the possible realities of a world in which super-athletes and genetically-made geniuses walk among us.