Following the launch of “The Genome Projects of three Extreme-Environment Animals” and the accomplishment of “The international Giant Panda Genome Project” in 2009, BGI officially announced “The International Big Cats Genome Project” on February 12th, 2010 in Shenzhen. The short-term target of this project is to finish the sequencing and assembling of the Lion, Tiger & Leopard’s genomes within one year, to explore the applications of genome sequencing technology in studies of animal behavior, conservation biology and other disciplines & fields. This project is initiated by groups of scientists from all over the world, including BGI, Peking University, Heilongjiang Manchurian tiger forestry zoo, Kung Ming Institute of Zoology, San Diego Zoo’s Institute for Conservation Research (USA) and others.
Lion, Tiger & Leopard all belong to the Big Cat Family. They are at the top of the ecosystem pyramid and directly or indirectly influence the population of primary consumers living on plants. They are playing important roles in the stabilization of the ecosystem.
Tiger is known as the King of the beasts, the biggest species in the Felidae family, and mainly inhabited in Asia. In general the tiger is a forest dweller but can also be found in grassland and swamp margins beyond woodland areas. Tiger is a solitary forest carnivore. Generally, each tiger has its own territory and they only socialize when mating. They live mainly on deer, wild pigs and buffalo. The stripes on its body provide excellent concealment.
The lion, one of the large felines comparable to tiger, is famous for its great power and fast speed. It is different from other felines for its sexual dimorphism and social behavior. The lion used to be widespread in the southeast of Europe, the Middle East, India and the African continent, but nowadays as a result of human hunting and invasion to their habitats, their populations have been largely reduced and the wild species are restricted only to a few areas in Africa.
Leopard is the smallest one of big cats but most adaptive feline. There are many different kinds of Leopards and they live in various environments, such as Golden leopard which is widely distributed in Asia and Africa, Cloud leopard which lives in southeast of Asia, Cheetah which is produced in desert and grassland region of Africa, and snow leopard which lives in southwest of China and adjacent countries. The leopards are powerful animals: they have sensitive smell and vision systems, can swim and also climb. These specialties make them an audacious ferocity carnivore with wide feeding habits.
Tiger is an idolized figure in the Chinese culture for a long time and a symbol of justice, bravery and dignity. Producing a high quality genome sequence of tiger in 2010, the Chinese Year of the Tiger, has far-reaching social impacts regarding the protection and conservation of the tiger species, the development and continuation of the Chinese culture. Therefore, BGI selects tiger as the starting genome of this project.
The tiger genome and genomics research is almost blank regardless of its importance of conservation. The tiger has a genome size of about 3Gb, which is approximately the same size as the human genome. The information of tiger genome will have far-reaching implications on many related scientific fields. It will also provide us genetic evidences to the better understandings of this important species. Firstly, the project will provide a scientific basis on the tiger breeding and artificial propagation.Furthermore, the groundbreaking exploration of genomics in many other areas by cross application, this plan will also promote the use & development of the genome sequencing technology. In addition,the results of genomic research can accurately identify the generation and lineage relationship of tigers. It will provide new and important models for the qualitative and quantitative understanding of the interaction between the environment and genetic factors.
In 2010, BGI will start up in succession the genome projects of Amur Tiger, South China tiger, Bengal tiger, Asiatic Lion, African lion, Cloud leopard，snow leopard and etc. Accomplishments of these genome projects will bring new knowledge on evolution and comparative genomics research in Feline family. These feline family animal genome projects are major contents of “the 1000 plant and animal reference genomes project" which has been initiated by BGI.
Besides the comparative genomics research in feline family animals, the hybrid offspring of tiger and lion is an ideal animal model to study the crossbreed of wild animal. BGI plans to launch tigon (a cross between male tiger and female lion) and liger (a cross between male lion and female tiger) genome project and epigenome project once the tiger and lion’s genome have been decoded. In many domesticated species, the crossbreeding is an important approach to produce new hybrids for heterosis phenotype, such as hybrid rice and mule, which is significant for human agricultural society. In contrast, the hybrid of wild species is more difficult than domesticated species hybrid. In wild environment, the cross-fertilization of different wild species is considered as a possible way that a new species emerges. Based on the deciphered genome and epigenome information of liger and tiglon, it is an opportunity to re-explain the definition of “hybrid” and “species” from the aspect of DNA sequence and chromatin variation.