Kim de Luca

We can’t predict exactly where lightning will strike. It’s somewhat random and depends on the context: A tree in a field might be a likely target, but that same tree might be safer in a city of high-rise buildings.

DNA damage is similar, says Kim de Luca, 34. De Luca has been investigating how our DNA gets damaged, whether some regions are more vulnerable, and if so, why. These are important questions. Our genomes accumulate damage throughout our lives, and this damage can cause diseases like cancer and neurodegenerative disorders.

And knowing which genes are affected isn’t enough, says de Luca. Cells vary in their structure: To get a full picture of where and how DNA damage occurs, we need to look at how it is happening in thousands of individual cells. “I am a fan of the details,” says de Luca. “The smaller, the better.”

To do this, de Luca and her colleagues engineered human cells to have a network of “damage sensors” that can be tracked. They did this by attaching a molecular tag to a DNA repair protein that the cells produced.

The tag is made up of a series of DNA bases that don’t normally occur in human DNA. When de Luca and her colleagues want to measure DNA damage, they can use an enzyme that specifically cuts DNA only where the tag is present. They can then run another test to essentially count the pieces of chopped DNA and take a closer look at those regions of the genome.

This approach could help scientists—and oncologists—better understand how a person’s cells might respond to existing cancer treatments, and how to develop more effective therapies.

But it can also be used to track how DNA changes over time. De Luca is using the same tools to study corals. “[Some corals] have lived thousands of years,” says de Luca, “and nobody understands why.” Her team is looking at how coral DNA mutates to learn how these animals evolved—and how they might fare with future climate change.