Two of the species most used for these purposes are the common albino mouse ( Mus musculus ) or the fruit fly ( Drosophila melanogaster ). However, there is another species which by its nature is more interesting for genetic studies and related development , the zebrafish. In this article we will talk about the characteristics and usefulness of this species.
The zebrafish ( Danio rerio ) is a small vertebrate, reaching 5 cm in length in its adult stage. It is a native species of Southeast Asia, popular in aquariums due to its resistance, large number of offspring and easy obtaining. The males and females of this species have sexual dimorphism, which means that their appearance is different. The body of the fish is transparent, which allows you to see its internal organs, and has several blue lines along the body.
The characteristics that make this species interesting for study in the laboratory are mainly two: the similarity of its genome with the human and the speed of its development . It is estimated that we share 80% of our genome with zebrafish, which makes it interesting for genetic studies. On the other hand, the fish reproduce continuously throughout the year, the females lay about 200 eggs and the development of the internal organs of the embryos is completed in just 24 hours.
Usefulness of zebrafish in the laboratory
Genetic studies carried out with zebrafish require a male to which a mutation is induced in the germ cells (sperm, in simple language), who has offspring with a non-mutant female giving rise to offspring that may or may not express the mutation (depending on whether it is dominant or recessive). Later these descendants are crossed with other fish giving rise to a second generation that allows studying the expression of recessive mutations .
In particular, mutations in genes related to embryonic development allow the evolutionary process of vertebrates to be studied in detail, one of the main applications of zebrafish. Here the advantage over the laboratory mouse is that zebrafish can be observed directly as they develop. In addition, it is the known species of vertebrate that has a greater number of coding genes, about 26,500, thus exceeding the 20,440 genes of humans or 22,000 of mice.
A striking skill
Another striking feature of the zebrafish is its regenerative ability . These fish can regenerate parts of their body that have been damaged or removed during their development stage, regenerating internal organs or the retina of the eye. Numerous studies have been carried out to better understand how these mechanisms work and to be able to replicate them in humans, particularly in spinal regeneration therapies or in treatments against muscular dystrophy.
The zebrafish genome has been completely sequenced, making it one of the best-studied genomes in the entire animal kingdom . Various mutant variants of zebrafish have also been studied, of which there is availability for experiments.
Zebrafish have enabled scientific advances in the fields of developmental biology , toxicology, oncology, reproduction, teratology (study of developmental abnormalities), genetics, neurobiology, cell line research, regenerative medicine, muscular dystrophies, and evolutionary theory. of vertebrates.