科学美国人60秒:Snake DNA Left in Bite ID's Serpent Assailant

Snakes still kill tens of thousands of people each year. Giving the antidote quickly can be the difference between life and death. But many bite victims cannot identify the species of their slithering assailants. Which leaves health care workers to make educated guesses about treatment. 
 
Now a first-of-its-kind study finds that it’s possible to analyze snake DNA left in the victim’s wound to identify the snake—and thus the correct antivenom. The preliminary findings were presented November 4th at the annual meeting of the American Society of Tropical Medicine and Hygiene in New Orleans. [Sanjib K. Sharma et al, Use of clinical predictors and molecular diagnosis to identify the species responsible for snakebite in rural Nepal]
 
Researchers collected samples from fang wounds from 749 people at three health centers in Nepal. They isolated snake DNA, sequenced it and compared it to sequences in a snake DNA database. Ultimately they managed to identify snakes responsible for 194 bites, 87 of which had harmful venom.
 
Such intricate genetic analysis is still not available in most settings, but could lead to speedier diagnostic methods for bite victims. The research team hopes to devise a fast test that would at least rule out certain common venomous snakes. The test would analyze DNA along bite marks and scan it for telltale signs of specific poisonous predators.
 
—Dina Fine Maron