Study looks at venom variation in closely related snake species

June 10, 2014
Sochurek's saw-scaled viper (Echis carinatus sochureki), found near Sharjah, United Arab Emirates and used in the study. Credit: Wolfgang Wüster

Specialist researchers from LSTM have identified the diverse mechanisms by which variations in venom occur in related snake species and the significant differences in venom pathology that occur as a consequence.

Working with colleagues from Bangor University and Instituto de Biomedicina de Valencia in Spain, the team assessed the composition of six related viperid snakes, examining the differences in gene and protein expression that influence venom content. The research, published in PNAS, also assessed how these changes in venom composition impacted upon venom-induced haemorrhage and coagulation pathologies, and how these changes can adversely affect antivenoms used to treat snakebite.

LSTM's Dr Nicholas Casewell, first author and NERC Research Fellow, said: "Our work shows that venom variation observed between related snake species is the result of a complex interaction between a variety of genetic and postgenomic factors acting on toxin genes. This can involve different genes housed in the genome being turned on or off in different snakes at different stages of venom toxin production. Ultimately, the resulting venom variation results in significant differences in venom-induced pathology and lethality and can undermine the efficacy of antivenom therapies used to treat human snakebite victims."

Every year, snakebites kill up to 90,000 people, mostly in impoverished, rural tropical areas, as well as causing thousands of debilitating injuries to survivors, in part the reason that snakebite has the status of a neglected tropical disease. Antivenom can work but its efficacy is largely restricted to the snake species used in its manufactures and is often ineffective in treating snakebite by different, even closely related species.

LSTM's Dr Robert Harrison, senior author of the study and Head of the Alistair Reid Venom Unit, said: "The findings underscore challenges to developing broad-spectrum snakebite treatments, because conventional antivenom is produced by immunising horses or sheep with the venom from a specific species of snake. Consequently, antivenin produced for one species of saw-scaled viper will not necessarily neutralise the venom of another species of saw-scaled viper, highlighting how changes in venom composition can adversely affect therapy."

Explore further: Research identifies importance of diet in snake venom evolution

More information: "Medically important differences in snake venom composition are dictated by distinct postgenomic mechanisms," by Nicholas Casewell et al. www.pnas.org/cgi/doi/10.1073/pnas.1405484111

Related Stories

Recommended for you

Orangutan females prefer dominant, cheek-padded males

September 1, 2015

Unlike most mammals, mature male orangutans exhibit different facial characteristics: some develop large "cheek pads" on their faces; other males do not. A team of researchers studied the difference in reproductive success ...

Plastic in 99 percent of seabirds by 2050

August 31, 2015

Researchers from CSIRO and Imperial College London have assessed how widespread the threat of plastic is for the world's seabirds, including albatrosses, shearwaters and penguins, and found the majority of seabird species ...

Researchers unveil DNA-guided 3-D printing of human tissue

August 31, 2015

A UCSF-led team has developed a technique to build tiny models of human tissues, called organoids, more precisely than ever before using a process that turns human cells into a biological equivalent of LEGO bricks. These ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.