The zebrafish (Danio rerio) is a tropical freshwater fish native to southeast Asia. Approximately 2.5-4 cm in length, it is mainly recognised by the horizontal stripes that run along the length of its body.
Use of zebrafish as a model organism
Zebrafish are used as a model organism to carry out research, primarily in the fields of genetics and developmental biology. A number of their morphological and physiological features make them useful as a model organism, one of which is their robust, transparent embryos that develop outside the mother. This makes it possible to view embryological development, and also allows for easier access to the embryo for manipulation (for example, altering the expression of certain genes through the use of morpholinos).
The similarity of zebrafish to humans is another important factor; being vertebrates, they are more closely related to humans than other model organisms such as Escherichia coli or Drosophilia.They also follow developmental processes similar to those observed in mammals. Following the sequence of the zebrafish genome in 2013, it was found that approximately 70% of human genes possess at least one zebrafish orthologue. Furthermore, 84% of human genes that have some connection with human disease have counterparts in zebrafish, which suggests that further study of these genes in zebrafish would increase understanding of a number of human diseases.
Zebrafish also have a short generation time of 2-4 months, meaning that it is possible to carry out experiments over a relatively short time frame. The large number of offspring produced (usually around 200 eggs) is also useful because it provides a large sample size to work with when carrying out research.
Zebrafish in research
Zebrafish were first used as a model organism by George Streisinger in the late 1960s at the University of Oregon, with the research culminating in the cloning of zebrafish, making them the first vertebrates to be cloned.
As explored by Verkerk AO and Remme CA. (2012), zebrafish can be used to research 'cardiac (patho)electrophysiology and ion channel disorders'. According to Verkerk and Remme (2012), zebrafish and humans' embryonic and mature heart rates and electrocardiogram morphology resemble each other enough to make them a useful research tool. Many charities researching heart disease have even advertised the use of zebrafish in their research, such as the British Heart Foundation's 'Mending Broken Hearts Appeal' due to the zebrafish's apparent ability to 'regenerate' its heart. Their original video can be found here: Mending Broken Hearts (2011)
- ↑ Wellcome Genome Campus. Why use the zebrafish in research? 2014. Cited [4/12/16]. Available from: http://www.yourgenome.org/facts/why-use-the-zebrafish-in-research
- ↑ Bedell VM, Westcot SE, Ekker SC. Lessons from morpholino-based screening in zebrafish. Briefings in Functional Genomics. 2011;10(4):181-188.
- ↑ Howe K, Clark MD, Torroja CF, Torrance J, Berthelot C, Muffato M, et al. The zebrafish reference genome sequence and its relationship to the human genome. Nature 2013; 496 (7446): 498-503.
- ↑ Wellcome Trust Sanger Institute, Family ties: Relationship between human and zebrafish genomes. 2013. Cited [4/12/16]. Available from: http://www.sanger.ac.uk/news/view/2013-04-17-family-ties-relationship-between-human-and-zebrafish-genomes
- ↑ Spence R, Gerlach G, Lawrence C, Smith C. The behaviour and ecology of the zebrafish, Danio rerio. Biological Reviews, 2008; 83(1):13-34
- ↑ Clark, K. J. , Ekker, S. C.. How Zebrafish Genetics Informs Human Biology. Nature Education 2015; 8(4):3
- ↑ Front Physiol. 2012;3:255. Epub 2012 Jul 10. [PMID: 22934012] doi:10.3389/fphys.2012.00255