GENOME OF INDIAN COBRA SEQUENCED
An International team of researchers have sequenced the genome of the Indian cobra, in the process identifying the genes that define its venom.
Present situation about Anti-venoms:
- Anti-venoms efficacy varies with producing side effects.
- In India, the challenge has been producing anti-venom for the species known collectively as the “big four”,
- The Indian cobra (Naja naja)
- Common krait (Bungarus caeruleus)
- Russell’s viper (Daboia russelii)
- Saw-scaled viper (Echis carinatus)
- Common anti-venom is marketed for the treatment of bites from the “big four”, but its effectiveness came under question in a recent study.
- The common anti-venom worked against the saw-scaled viper and the common cobra.
- But this anti-venom fell short against some neglected species and also against one of the “big four” – the common krait.
Challenges in producing Anti-venom:
- Venom is a complex mixture of an estimated 140 odd protein or peptides.
- Only some of these constituents are toxins that cause the physiological symptoms seen after snakebite.
- But anti-venom available today does not target these toxins specifically.
- Anti-venom is currently produced by a century old process called “Horse Technique”
- Horse Technique: In this technique, a small amount of venom is injected into a horse or sheep, which produces antibodies that are then collected and developed into anti-venom.
Problems in Horse Technique:
- It is expensive, cumbersome technique and comes with complications.
- Some of the antibodies raised from the horse may be completely irrelevant.
- The horse also has a lot of antibodies floating in its blood that have nothing to do with the venom toxins.
- Our Immune system recognises horse antibodies as foreign and when anti-venom is given our body mounts an antibody response. This lead to serum sickness.
Significance:
- This genome sequence can provide a blueprint for developing more effective anti-venom.
- The cobra genome sequence is of really high quality.
- Sequence information of the genes that code for venom proteins is very important for the production of recombinant anti-venoms.
- In the Indian cobra genome, the researchers have identified 19 toxin genes, in that only one that should be addressed for snakebite treatment. This decoding will help to create a safe and effective anti-venom using synthetic human antibodies.