An article published in the journal “Nature Genetics” reports the DNA sequencing of the spectacled cobra, one of the so-called “Big Four”, the four most venomous and dangerous snakes in India. A team of researchers employed a number of genetic techniques that led to the identification of 23,248 genes that encode proteins, including 12,346 genes that regulate its venom glands. The knowledge of this snake’s genome will help develop better antidotes for its deadly venom and the proteins contained in that venom could also be useful for developing various types of drugs.
The spectacled cobra, also known as Indian cobra because it lives throughout southern Asia but has a greater concentration in India, also known as Asian cobra, or binocellate cobra, (Naja naja) is a small snake since it has an average length between 1 and 1.5 meters with peaks, especially in Sri Lanka, just over two meters, but lethal due to its neurotoxic and cardiotoxic venom. It’s one of the four most venomous and dangerous species in India and in general in southern Asia.
There’s a medical treatment that can save the victims of the spectacled cobra’s bite but in India alone the “Big Four” still kill almost 50,000 people a year and thousands more suffer lasting physical consequences. The genetic study of this snake offers new information on its venom, starting with the identification of 19 genes linked to the main toxins contained in it.
Professor R. Manjunatha Kini of the Department of Biological Sciences at National University of Singapore, one of the authors of this sequencing and an expert in research on snakes, stated that for the first time there’s a complete list of genes related to the toxins present in the spectacled cobra’s venom. He also stressed the need to modernize the development of an antivenom using modern technologies. By obtaining the genome of the other three Big Four species, scientists will have a complete platform to develop a universal antivenom against snakebites that can be used in a very large area.
Currently, the development of antivenoms is based on antibodies generated in horses to which a snake venom is injected. This is a tricky approach primarily because it’s dangerous for the horse and in any case expensive. A complete knowledge of the toxins contained in the spectacled cobra’s venom, or of another species, will help develop more modern biotechnology-based approaches.
There are proteins in the venom of snakes such as the spectacled cobra that have effects such as lowering blood pressure, as anticoagulant or as pain killer. For this reason, their study has been exploited for some time in the development of new drugs, and again the complete knowledge of the toxins contained will lead to progress.