This is Science Friday. I'm Ira Flato, coming to you today from the studios of WBEZ in Chicago.

Later this hour, the chemistry and light tricks that bring us the rainbow, the science of colors.

First, one of the scientific advances that's taken the biology world by storm is the gene editing

technique known as CRISPR. It allows researchers to

fairly easily make edits to genes, sniffing out one sequence, inserting another in its place,

but it appears there could be a downside to the technique. Joining me now to talk about it is

Sharon Begley. She's senior science writer at Stat News, based in Boston, and author of an article this week

about new research findings in the CRISPR world.

Welcome back to the program, Sharon.

Thank you for having me, Ira.

So tell us about this.

What exactly did these research papers find?

These were two papers published earlier this week in the journal Nature Medicine,

and they both converged on a similar conclusion.

Both used CRISPR, which, as you described, is the latest genome editing technique, to alter cells.

One group used stem cells, the other group used eye cells, both human.

And they found that it was much easier to CRISPR the cells, but we're now using CRISPR as a verb,

if those cells lacked a key anti-cancer gene and anti-cancer pathway.

So to flip that around, if cells are successfully edited, if their genomes are successfully edited

with CRISPR, that raises a concern that maybe there's something wrong with those cells,

i.e. that they lack a crucial anti-cancer pathway.

So that's all that the studies did. They didn't find that anybody was going to get cancer from

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