Modifying cancer cell genomes | The Big Idea

On the quaint campus of Cold Spring Harbor Laboratory on Long Island, Dr. Jason Sheltzer hopes to find a treatment for cancer.

"CRISPR is a pair of molecular scissors that allows you to precisely change the DNA in a cell or an organism," he said.

CRISPR, short for Clustered Regularly Interspaced Short Palindromic Repeats, is a molecular tool that allows scientists to go in and modify specific cells.

"We can now use CRISPR to go in and make precise modifications in cancer cell genomes and then ask how that affects cancer cell behavior," Sheltzer said.

For the past three years, Sheltzer has been studying the cancer cell line. He hopes discoveries inside his lab will lead to clinical trials and ultimately improve treatment for cancer in the future.

"I think that it is a good time to be a scientist and it's a bad time to be a cancer cell," he said.

Researchers are also working to see if CRISPR can cure genetic illnesses such as cystic fibrosis and sickle-cell anemia. It has been already been successful proven in mice. Clinical trials are underway in humans.

But some ethicists question whether the gene-editing technique should be used for enhancements, such as the more perfect person? Dr. Sam Packer, a bioethicist at Northwell Health, said there is not nearly enough information to fully know if it is safe.

"We don't know enough about gene editing and if there's even a little risk to deal with something that's enhancing just doesn't make for an ethical balance," he said.

While CRISPR is still being heralded as a groundbreaking medical breakthrough, serious concerns remain about genetic editing potentially doing more harm than good.

"I think this is a bump in the road that makes you want to take a pause," Packer said.

In May, two studies published in Nature Medicine from two different teams of scientists reached the same conclusion: CRISPR-edited cells intended to treat disease may actually cause cancer.

"When CRISPR goes into a cell and it's trying to alter a gene sequence, it might inadvertently, called off-target, go to this gene and alter it," Packer said. "That's what it did with p53, and p53 is a cancer-protected gene."

So while findings that link CRISPR to possibly cause cancer are a reminder that we still have time until we know its true impact. Doctors like Sheltzer are making incredible progress that could change modern medicine as we know it.