New gene-editing technology offers promise but poses threat to future generations
By David Prentice, PhD | December 03, 2015
Excerpted from "Scientists debate the ethics of an unnerving gene-editing technique," Washington Post, December 1, 2015 - Genetic engineering isn't new, but CRISPR is, and it's a stunningly fast, flexible, cheap way to manipulate the code of life. It's so revolutionary — and unnerving — that hundreds of scientists, policymakers and the president's science adviser gathered Tuesday in Washington for the start of a three-day summit on the implications of this astonishing technology.
Developed only in the past four years, the CRISPR technique exploits a natural process used by ordinary bacteria to defend against invasive viruses. It enables rank-and-file scientists — just about anyone with a modern laboratory and the right skills — to alter specific genes within plants and animals and make those changes heritable. This kind of gene editing could potentially be used in gene therapies targeting a variety of devastating, heritable diseases.
But many researchers argue that it is too soon, and potentially too dangerous, to tinker with the human genome in a way that is passed down to future generations. One objection is simply pragmatic: Biological systems are extremely complex, and changing human genes could have unintended and undesirable consequences. And many bioethicists are not comfortable with the prospect that gene editing could be used for purely cosmetic enhancements, or in an attempt to give certain people physical and intellectual advantages.
“The overriding question is when, if ever, we will want to use gene editing to change human inheritance," summit chair David Baltimore of Caltech said in his introductory remarks.
CMDA Member and Research Director at Charlotte Lozier Institute David Prentice, PhD (excerpted from his testimony before Institute of Medicine on Mitochondrial Replacement Therapy and 3-Parent Embryos, with additional comments for CMDA): “The early researchers who did transfer mitochondria-containing ooplasm noted that this was ‘germline genetic modification.’ Current popular terminology refers to these individuals as ‘3-parent babies.’ The U.S. FDA itself in 2002 called this ‘de facto germline gene transfer.’ If this were not the case, the Committee would not be concerned about follow-up with not only the genetically-reconstructed individuals but also their progeny.
“In fact the phrase used —‘mitochondrial replacement therapy’—is a misnomer, as it is neither mitochondrial replacement nor therapy. In point of fact, what is being transferred is the nucleus. So these proposed techniques foster human cloning.
“They use the same manipulative techniques and skills used in somatic cell nuclear transfer, a.k.a. ‘Cell Nuclear Transfer,’ i.e., human cloning, by micromanipulation of nuclei and of oocytes.
“The newer gene-editing techniques (e.g., CRISPR) now under discussion also raise concerns about germline gene engineering, including genetically modified babies who will pass on any heritable gene alterations. No existing individual is treated using the proposed techniques. These are all non-therapeutic interventions. Rather, these techniques all create new human embryos with altered genetic composition, genetically engineered individuals who, it is hoped, will not inherit disease, or who may be designed to have enhanced or added genetic characteristics. Put another way, these techniques all evince a distinct lack of concern, even a disdain, for those individuals who currently suffer from disease, instead focusing solely on the design of new, genetically correct individuals to take their place. We should put a hold on any experiments with human beings and designing a brave new human, and focus our efforts on therapies (including genetic treatments) that address existing patients.”