January 15, 2015

Discovery Lecturer outlines new genome editing technique

A mere 30 months since it was first described in the online edition of Science magazine, a new genome editing technique has, by many accounts, revolutionized the study of genes and disease.

Flexner Discovery Lecturer Jennifer Doudna, Ph.D., third from right, with, from left, John York, Ph.D., Lawrence Marnett, Ph.D., Walter Chazin, Ph.D., Vanderbilt Chancellor Nicholas S. Zeppos and Provost Susan Wente, Ph.D. (photo by Steve Green)

A mere 30 months since it was first described in the online edition of Science magazine, a new genome editing technique has, by many accounts, revolutionized the study of genes and disease.

Last year Chinese researchers reported they had used the technique to modify two genes in one-cell embryos of monkeys, thus creating what they called “genome engineered” primates. Which raises a profound ethical issue — should the new technique, called CRISPR/Cas9, be regulated?

That was the final question posed to Jennifer Doudna, Ph.D., of the University of California, Berkeley, following her Flexner Discovery Lecture last week on the technique her team developed in 2012.

“This is a huge question,” said Doudna, a recipient of a 2015 Breakthrough Prize in Life Sciences for her team’s achievement. “You realize that germline editing in humans probably will work, too. Is that where this should go?”

“I don’t have answers for that,” she said, “(but) I think it’s really key to make sure that people are educated about what this is and how it works so they can think about it in an informed way.”

Doudna, a Howard Hughes Medical Institute investigator and Li Ka Shing Chancellor’s Chair in Biomedical Science and Health at UC Berkeley, was introduced to an overflow crowd in a Light Hall lecture room by Vanderbilt University Chancellor Nicholas S. Zeppos.

Zeppos said Doudna is “an incredible scholar” whose “groundbreaking science is really revolutionizing the way that we think about fundamental questions in basic science.”

CRISPR, which stands for Clustered Regularly Interspaced Short Palindromic Repeats, is a mechanism bacteria use to protect their genomes from invading viruses and plasmids. Doudna and her colleagues described a CRISPR-associated enzyme, Cas9, which, when guided by small RNA sequences, can cleave specific, invading DNA sequences.

The potential to harness this ancient bacterial defense mechanism for “RNA-programmable” genome editing in research was immediately recognized.

Doudna said her lab’s discovery underscores the importance of basic research. “I set out to understand how bacteria fight off viral infections … never anticipating (this) was going to lead to a new technology for genome engineering,” she said.

“It’s been an incredible ride … Stay tuned.”

The lecture was sponsored by the Vanderbilt Institute of Chemical Biology, the Vanderbilt Center for Structural Biology and the Department of Biochemistry, and also was part of the department’s “Frontiers in Biochemistry” seminar series.

For a complete schedule of the Flexner Discovery Lecture series and archived video of this and previous lectures, go to www.mc.vanderbilt.edu/discoveryseries.