No More Genetic Heart Defects?
If you had a known genetic predisposition to a deadly disease or condition, would you take advantage of technology to remove the DNA which causes the disease in your offspring? Even if it meant you could not procreate the “natural” way but would need to have in vitro fertilization? Is the thought of this kind of genetic editing too Brave New World for mainstream medicine?
Recently, researchers at the Oregon Health and Science University used CRISPR technology to identify and remove the gene which causes hypertrophic cardiomyopathy (HCM) from an embryo created specifically for this study (not implanted). HCM is a genetic heart condition which causes a thickening of the heart muscles and is one of the leading causes of sudden cardiac arrest in young athletes. It is thought one in every 500 people in the US have this condition, but most have no symptoms or mild symptoms are wrongly attributed to other conditions. For those who do have it, however, they are literally a ticking time bomb and can suffer sudden cardiac arrest at any time. Do we owe it to future generations to eradicate this condition completely?
The most impressive aspect of this accomplishment is it involves germline DNA, defined by the NCI Dictionary of Genetics Terms as “tissue derived from reproductive cells (egg or sperm) that become incorporated into the DNA of every cell in the body of the offspring. A germline mutation may be passed from parent to offspring.” In a nutshell, this means if a bad mutation is corrected or removed at the time of fertilization, it can no longer be passed along to direct descendants. Understanding this is possible gets the “what if” machine rolling and more questions than answers are available right now. What if there were no more inherited cancers like breast, colorectal, prostate, or ovarian? Why stop at cancer? What if we could also eliminate other single-gene diseases like cystic fibrosis, sickle cell anemia, Huntington’s, or Marfan’s?
While the thought of reducing human suffering should only be positive, some have claimed this same technology opens up the possibility for creating ‘designer babies’. It is important to note in this study CRISPR was not used to enhance a DNA strand with the goal of creating desirable attributes like hair and eye color, athletic ability, or IQ (all of which have been discovered to involve a complex combination of genes), but instead was used to correct a DNA strand by removing a defective gene from a male donor’s sperm so as the embryo developed it could correct for the missing gene and repair itself using the healthy mother’s genetic material.
Of course, the hope is we can correct for genetic defects either in the womb or after the child is born, ensuring the gene never gets “turned on” during the person’s lifetime. If DNA testing were done to determine what genes a person has which cause everything from ALS to male pattern baldness, a future solution may be a one-time treatment to knock out all the ‘bad’ or undesirable (from a medical standpoint) genes. It could be a literal silver bullet for disease. What the future holds for the possible applications of this technology is mind-boggling.
September 13, 2017 at 4:03 pm, Michael Mueller said:
1. Do we think this won’t lead to eugenics, and “engineered babies” for the rich?
2. This article postulates the elimination of this gene from the gene pool, but that ignores that we are devolving and this, or worse, gene anomalies will still appear even if we were able to do this will ALL embryos.
3. Are you not afraid of the always unintended consequences of such actions. I AM.
September 25, 2017 at 9:09 am, AED Superstore said:
Thank you for your comment. To address your concerns:
1. As noted in the article, at this time the technology has only been shown to eliminate an undesirable single gene condition, not enhance DNA strands. “Designer babies” would require technology much more advanced as physical attributes which some would consider desirable are the result of multiple gene combinations which are highly complex within the DNA strand. Impossible? Maybe not at some later date, but not currently as far as we know.
2. Unsure as to what you mean by “we are devolving”, but yes, gene mutations occur through generations. Again, as noted in the article, the goal is to find a way to test an individual once they are born and can undergo a one-time treatment to ensure a gene which causes diseases are never “turned on” during a person’s lifetime.
3. If history has shown us anything, it’s there are often unintentional consequences to scientific discoveries – some good, some bad. There will always be those wanting to use such discoveries for personal gain or nefarious purposes, but should this stop the scientific community from trying to find permanent ways to eliminate debilitating diseases?
Finally, as with all medical procedures, the hope is there will be regulations in place to uphold both moral and ethical practices within the scientific community with this technology.