For modern science, one of the main challenges in relation to biology and biodiversity is the preservation of species, which are at an imminent threat of becoming extinct. According to an article published in the abc news, around 40,000 species become extinct every year. While some species, which were recognized as nearing extinction earlier in the decade, have already disappeared from the planet earth, many others are in line for the same fate. However, DNA banks formed by freezing endangered animals’ DNA could be the key against extinction and it has become one of the most interesting areas of study for modern day scientists.
One of the main tasks of a DNA bank is to preserve the genetic material pertaining to almost 7,200 species of endangered animals listed by the World Conservation Union’s (IUCN) Red List. Thus, several zoos, conservation groups and academic institutes have come forward to establish such banks in various parts of the world. However, the foremost and the largest DNA bank is established in the San Diego Zoo in the name of ‘Frozen Zoo’. Since its establishment in the year 1972, there were a few other organizations starting similar ventures and among them, Cincinnati Zoo and Botanical Gardens, Audubon Society, and the Frozen Ark project in the UK are some of the main contributors to the DNA banks.
The technology behind a DNA bank is to freeze samples of sperm, ova, embryos, tissue samples and serum, belonging to an endangered species, in liquid nitrogen at around -196 degree to -373 degrees Celsius. Scientists have recognized these temperatures as able to preserve tissue samples indefinitely as long as the desired temperatures are maintained throughout.
As mentioned earlier, the main focus of a DNA bank is the conservation although there are many other scientific gains by having such a bank. Among such uses, studying the physiology of an endangered or extinct species and helping the forensic work in relation to illegal trading and domestication of endangered birds and other animals should be highlighted.
In relation to conservation, a DNA bank could help preserve the ‘gene pool’ of an endangered species and therefore could be injected into small populations of such endangered animals and improve their chances of survival. The basic principle behind this intervention is, as the endangered species population fall, the inbreeding will lead to manifestations of birth defects, increased risk of diseases, and less ability to survive by such animals in case of natural disasters. Thus, by injecting new genetic material, which belongs to the same species, would avoid such manifestations and could promote better survival among the existing animals.
Apart from maintaining the gene pool, DNA banks will also have the capability of regenerating ‘new individuals’ as in the case of reproducing a new animal using a preserved embryo or even from preserved eggs and sperms. Such instances have taken place although in experimental level in 1999 and 2000 as in the cases of reproducing an African wildcat kitten and a Caracal cat respectively at the Audubon Center of Research.
Thus, it is possible that at some point in time, even the extinct animals could be given life and until such date, the scientists are working tirelessly using frozen DNA banks, to preserve the ‘gene pool’ of all the endangered species.