The tiny zebrafish uses 80% of its genes to benefit 100% of the people!

There is a group of cute little elves. When they swim in groups, their bodies are agile and light, and they are no less than the zebras running at lightning speed on the African grasslands. They originally lived in swamps, ponds, and rice fields in India and Bangladesh, but in order to cure human intractable diseases, they swam all the way into laboratories of universities, research institutes, and companies around the world to test drugs on themselves. They are great experimental animals - zebrafish.

Danio rerio, also known as zebrafish, blue stripe fish, flower stripe fish, zebra danio, belongs to the genus Danio of the family Cyprinidae, subclass Actinopterygii. This small animal is 3-5 cm long, slender, like a delicate spindle, with multiple dark blue stripes from the head to the tail fin, just like a zebra, so it has the beautiful name of "zebrafish". Zebrafish reach sexual maturity 3-4 months after hatching, and the gender is easy to identify: the blue stripes of male fish are yellowish, with lemon stripes; the blue stripes of female fish are blue, bright and colorful, with silver-gray stripes. In addition, the body of female fish is fuller and stronger than that of male fish, and each fin is shorter than that of male fish. The natural lifespan of zebrafish is about 3 years. They can mate and lay eggs all year round. The spawning cycle is 5-7 days. A pair of healthy adult zebrafish can lay more than 200 eggs at a time. It is worth mentioning that the embryo is completely transparent and develops very quickly, which not only makes it easy to observe the entire process of embryonic development, but also facilitates experiments.

Zebrafish are diploid animals with 25 pairs of chromosomes, dioecious sexes, sexual reproduction, and no confirmed sex chromosomes. 70% of human protein-coding genes are related to genes in zebrafish, and 84% of known human disease-related genes can be found in the zebrafish genome. Therefore, zebrafish are often regarded as "water mice". Through this special "tool" of zebrafish, a large number of human disease models can be established to explore the genetics and pathogenesis of human diseases.

Zebrafish has not been introduced into the field of biological research for a long time and can be said to be the youngest model animal, but its excellent characteristics have quickly attracted the favor of scientists in various fields, and various types of research using it as a tool have developed rapidly. In the past 30 years, research using zebrafish as experimental materials has developed rapidly, and the total amount of research has expanded nearly 20 times. Zebrafish has become the second largest vertebrate model animal in life science research after mice. As of October 2021, there are 1,500 zebrafish laboratories registered in the International Zebrafish Model Organism Database (ZFIN).

In scientific research applications, scientists use zebrafish as a supplement to mammals. In the fields of developmental biology (early embryonic development, signaling pathways), individual development mechanisms, genomics, molecular biology, cell biology, genetics, immunology, neurobiology, oncology, disease mechanisms, pharmacology (drug safety evaluation, new drug screening), animal husbandry and veterinary medicine, aquaculture (fish biological evolution), ecotoxicology and environmental testing, a group of scientists have turned their attention to zebrafish and have achieved remarkable scientific research results.

At present, zebrafish has been recognized by the International Organization for Standardization (ISO) as one of the five fish experimental animals. It is the third largest experimental animal after mammals such as rats and mice, and is currently the only vertebrate suitable for high-throughput drug screening. There are six zebrafish resource centers around the world. In 2012, my country established the National Zebrafish Resource Center (CZRC) at the Institute of Hydrobiology, Chinese Academy of Sciences.

Small but capable; small fish, big world. We hope that the tiny zebrafish will play a greater role in the big world of human life and health.