Zebrafish (scientific name Danio rerio) are freshwater fish native to South Asia that can be a little over half an inch to two inches long. About 70% of their genes share a common ancestor with our genes—even more if you look specifically at disease-causing genes. Like us, they have a spinal cord, eyes, a heart, a digestive tract and many other physiological similarities. This makes zebrafish an ideal model to study people.
While zebrafish are like humans, they are also really different. A recent article in The Physiologist Magazine outlined why zebrafish are such valuable research models, and it’s because of those differences. Their embryos develop outside their mother’s body, allowing scientists to directly watch and manipulate their development. These embryos and the very young fish, called larvae, are also transparent. This transparency allows researchers to “watch real activity inside of the vertebrae animal,” said neuroscientist Joseph Fetcho, PhD. Fetcho is working on ways to observe the zebrafish brain even after the skull becomes opaque. He explains that this advancement would allow researchers to study “development … plasticity and learning, and you could do degradation and neurological disorders and stuff through the entire life of vertebrae animals.”
Zebrafish transparency also helps researchers have a better understanding of how the nervous system develops. “It’s changing the way people think about how you build a brain …. There’s so much more than we even imagined, and the fish allow us to just watch,” developmental neuroscientist Sarah Kucenas, PhD, explained.
The culture of the zebrafish research community is another unexpected way zebrafish research helps advance science. Zebrafish researchers are known for their openness in sharing materials and techniques with one another and helping move science forward by making sure everyone has the tools they need. It’s a practice that started early with the pioneers of the field and continues today through initiatives like the Zebrafish Information Network.
All these advantages make zebrafish a valuable resource for a wide range of research, from neuroscience to cancer to tuberculosis. That’s a lot of reasons to be grateful to such a tiny fish!
For a deeper dive into how zebrafish help scientists understand the human body, read the full article.