Developmental geneticist Ryan Thummel and oncologist Jeffrey Taub in a zebrafish lab at Wayne State University. (COURTESY OF CHILDREN’S HOSPITAL OF MICHIGAN FOUNDATION)

The key to early detection of childhood leukemia might be found in thousands of tiny fish soon to be swimming around in a Wayne State University lab in Detroit.

A new research project is using zebrafish to identify genetic and environmental factors that in combination may lead to the development of childhood leukemia. Leukemia is the most common cancer in children and teens, accounting for almost 1 of every 3 such cases.

The researchers hope to find out whether a common pesticide flips a switch in a specific gene, causing leukemia in children.

Previously, researchers aided by Kids Without Cancer, a nonprofit based in Detroit, learned to breed zebrafish with the human leukemia genes.

“We had so much success with our original support that we saw the potential of additional scientific breakthroughs if we could ramp the research up,” said Christina Vandenberg, executive director of Kids Without Cancer.

Now, they are looking for the trigger that causes some children with those genes to develop leukemia, according to developmental geneticist Ryan Thummel, an assistant professor of anatomy and cell biology at Wayne State’s medical school.

The fish are much cheaper than the mice traditionally used in such experiments. Keeping a mouse can cost up to $100 per year, compared with $1 a year for a fish. And there’s another advantage: Researchers can introduce various triggers to thousands of the animals at once, an approach that allows them to study a large number of diseased fish at the same time.

“Zebrafish can produce thousands of offspring from a single mating event,” Thummel said. “This allows us to screen genetically similar siblings on a very large scale.”

The first pesticide to be tested will be propoxur, which is commonly used against fleas and other insects.

The project grew out of work done by Jeffrey Taub, chief of oncology at Children’s Hospital of Michigan, to identify children who might develop leukemia. He would like to be able to use blood already taken for newborn screenings to test for the gene. Finding it would allow doctors to monitor those children.