Letter from the President

Talking Points 

It is my honor to be writing my first Letter from the President in the IZFS News Splash. The News Splash is how the IZFS communicates with you, our members around the world. It notifies you about upcoming conferences and reviews past ones (19th IZFC Meeting Report). It highlights exciting recent zebrafish research as seen through the eyes of some of our early career members (Science Spotlight and Science Spotlight); it profiles current (Meet IZFS Awardees: CBC, Streisinger, and Nüsslein-Volhard) and former members of the community who went on to exciting non-academic careers (Alternatives to Academia). Finally, it provides timely advice on practical issues that the community faces (Shipping Zebrafish Internationally).  

These are difficult and uncertain times to be in science, particularly in the United States. Science is under attack at U.S. universities and at the organizations that the world has looked to for trustworthy, science-based information on health and disease. New and confusing directives on phasing out animal research in favor of organoid and AI-driven approaches has alarmed those of us who understand that these alternative models, while complementary, cannot model the complex cell and tissue interactions that underlie the development and function of living organisms. Over the past 30 years the zebrafish has been instrumental in discovering these interactions and their underlying genetic mechanisms. But the zebrafish has also had direct impacts on our understanding and treatment of human disease. Below are three “talking points” for you, the members of the IZFS, to take to your friends, families and elected officials to tell them about the biomedical importance of zebrafish research in particular and model organism research in general. These are a few examples; there are many others.  

1. Understanding Human Genetic Disease: The vertebrate genome of zebrafish means that they can be used to validate the causality of genetic variants identified in the genomes of humans with rare genetic diseases. Recently, researchers at Sick Children’s Hospital in Toronto made zebrafish mutants in two new genes identified in patients with congenital diarrhea and enteropathies (CODEs). The zebrafish mutants have intestinal abnormalities reflective of the human disease state. These models can now be used to understand the developmental basis of the disease.  

2. Drug discovery: The small size and aquatic habitat of zebrafish lend it well to drug discovery for complex human disorders. For example, researchers at the University of California San Francisco, have made a zebrafish model of Dravet syndrome, a severe genetic form of epilepsy. They have used it to identify clemizole hydrochloride and other serotonin receptor agonists as potent anti-epileptics. Clemizole hydrochloride and its derivatives are currently in a multicenter Phase III clinical trial which will be completed in 2026.  

3. Cancer treatment: The external development of zebrafish embryos and the fact that they lack adaptive immunity makes them accessible to cell transplantation, including of human tumor cells. In her lab at the Champalimaud Center in Lisbon, Portugal, Rita Fior (profiled in a previous issue of the News Splash) has developed a “zebrafish avatar” model for optimizing cancer treatment. Tumor cells collected after surgery are transplanted into zebrafish larvae which are then treated in a multi-well format to find out which of a range of approved drugs for that kind of cancer works best at preventing tumor growth.