Experts

Experts explain the ‘CRISPR’ practice: A controversial gene editing technology

This summer, researchers in Oregon used a technology called CRISPR to edit out disease causing genes in a human embryo for the first time.

CRISPR, or Clustered Regularly Interspaced Short Palindromic Repeats technology, could eventually be used to eradicate serious genetic diseases in humans, but it also raises ethical questions and concerns, some people fearing the method might be used to create offspring with desirable traits — “designer babies.”

To learn more about CRISPR, The Daily Orange spoke with Kate Lewis, associate professor of biology at Syracuse University; Erik Carlson, a plant science and biotechnology master’s student at the State University of New York College of Environmental Science and Forestry; and W. Henry Lambright, political science and public administration professor at SU.

The Daily Orange: What is CRISPR technology and how is it used?

Kate Lewis: CRISPR is a method of gene editing that cuts the DNA in a precisely determined place and can be used to edit genes that are already present or to place genes where you want them. You can use it in almost any animal cell, including in humans.

The D.O.: How was it used in human embryos this summer?

Erik Carlson: This is the first case in the United States where they have edited the genes of embryos using CRISPR. … In the Oregon case, they used CRISPR to find the mutated gene, cut it out and replace it with a normal functioning gene that everyone else has.

The D.O.: What are potential complications that the use of this technology could pose if it ever became regular practice?

K.L.: When dealing with CRISPR, you have to do the gene editing in the embryo before the first cell duplicates and becomes multiple cells, and then make sure that you’ve got the correct change that you wanted while the embryo is still in that one cell stage. If you wait until the embryo divides into multiple cells, the desired effect might take place in one cell but not the others.

E.C.: Right now, using CRISPR on human genes is just in the research phase. Some of the problems that might occur when using this technology that they haven’t been able to research into yet, is something called the “off-target” effect. That’s when CRISPR makes cuts in the DNA where it’s not supposed to. CRISPR is known for being a very accurate and precise tool, but nonetheless that is something that needs to be researched, to make sure that there aren’t going to be any deleterious mutations that could occur when using it.

The D.O.: How likely is it that this technique would become regular practice? What are the possible policy hurdles it could face if it became regular practice?

Henry Lambright: CRISPR is new and potentially quite attractive to some people for health reasons. However, it is also potentially high risk and even repugnant to those who are not ready for the concept of “designer babies.” So moving in that direction would likely face enormous barriers, including political ones.

The D.O.: Why is there controversy surrounding this issue?

K.L.: Unless mosaicism can be avoided, and all of the embryos have the desired change in the one cell stage, you have to be prepared to kill the embryos that do still have the genetic defect.

E.C.: It’s a very scientifically heavy concept to understand, and I think a lot of new technologies face a lot of controversy because people don’t fully understand them.

The D.O.: There has been concern that gene editing could lead to people wanting to edit things such as eye color, hair color, height, etc. in their offspring. How likely is this to happen with CRISPR technology?

E.C.: The thing with genetic diseases is that they usually affect a single gene, and so you can go and replace that single gene and have the desired effect. Things like height and eye color are determined by multiple genes, and editing them is somewhat of a more complicated process. I believe that using CRISPR will be reserved for severe diseases, at least in the United States.

The D.O.: What genes can or cannot be edited with CRISPR?

E.C.: All genes in theory can be edited with CRISPR. However, the genes that have been given a green light to be researched with CRISPR are genes that have to do with serious genetic diseases, such as cystic fibrosis or Huntington’s disease.