Reengineering Life

A New Kind of Gene Editing Could Fix What CRISPR Can’t

The technique is capable of precisely editing mitochondria

Emily Mullin
Published in
4 min readJul 14, 2020
Photo illustration. Image: 3d_man/Shutterstock

Reengineering Life is a series from OneZero about the astonishing ways genetic technology is changing humanity and the world around us.

Ever since CRISPR was first used to edit human cells in a dish in 2013, scientists have been hopeful about its potential to treat — and hopefully, eliminate — a wide spectrum of genetic diseases.

With the first experiments to use CRISPR in people underway, the gene-editing technique is showing promising signs in a few patients. But it turns out not all DNA is amenable to CRISPR.

Some genetic diseases, like those caused by mutations in the genome of the mitochondria — the body’s energy sources — can’t be corrected with CRISPR. Last week, a team at the Broad Institute of MIT and Harvard and the University of Washington School of Medicine announced that they figured out how to precisely edit mitochondria for the first time.

The discovery could help scientists better understand mitochondrial diseases and test treatments for these disorders, which affect about 1,000 to 4,000 babies born in the United States every year. Philip Yeske, science and alliance officer at the United Mitochondrial Disease Foundation, a patient advocacy organization based in Pittsburgh, says the results are exciting. “At minimum, it opens up a whole field of research,” he tells OneZero.

You might remember from high school biology that mitochondria are the powerhouses of the cell. These structures are responsible for converting energy from food and creating most of the energy the body needs to sustain itself. Mitochondria have their own DNA, and when that DNA goes awry, cells break down, and eventually, whole organs begin to malfunction.

Mitochondrial diseases commonly affect infants and children but they can occur at any age. Some of these disorders can kill…



Emily Mullin

Former staff writer at Medium, where I covered biotech, genetics, and Covid-19 for OneZero, Future Human, Elemental, and the Coronavirus Blog.