Causes and Consequences of Snake Venom Variation

Abstract

Snake venoms are mixtures of toxins that vary extensively between and within snake species. This variability has serious consequences for the management of the world’s 1.8 million annual snakebite victims. Advances in ‘omic’ technologies have empowered toxinologists to comprehensively characterize snake venom compositions, unravel the molecular mechanisms that underpin venom variation, and elucidate the ensuing functional consequences. In this review, we describe how such mechanistic processes have resulted in suites of toxin isoforms that cause diverse pathologies in human snakebite victims and we detail how variation in venom composition can result in treatment failure. Finally, we outline current therapeutic approaches designed to circumvent venom variation and deliver next-generation treatments for the world’s most lethal neglected tropical disease.

Insights into how development and life-history dynamics shape the evolution of venom

“…Snakes are among the most studied venomous animals, largely due to the significant adverse effect of their bites on human health (reviewed in Gutiérrez et al [ 11 ]). While venom composition has been the subject of the majority of these studies [ 12 ], research investigating the development of their venom apparatus is attracting considerable attention from evolutionary and developmental biologists [ 8 , 10 ]. This system typically consists of a gland loaded with venom and delivered using specialized fangs [ 13 – 15 ].…”

Novel Bradykinin-Potentiating Peptides and Three-Finger Toxins from Viper Venom: Combined NGS Venom Gland Transcriptomics and Quantitative Venom Proteomics of the Azemiops feae Viper

“…To date, it has been established that, despite the huge variety of toxins, they can all be attributed to a limited number of families either possessing enzymatic activities (e.g., phospholipases A 2 (PLA2), snake venom serine proteases (SVSP), snake venom metalloproteinases (SVMP)) or without such activities (e.g., lectins, three-finger toxins (3FTx), Kunitz-type inhibitors, natriuretic peptides). The variation in the composition of venoms occurs at all taxonomic levels [1], but the most drastic differences are evident at the level of families and subfamilies. As coagulopathies are induced mostly through an enzymatic pathway, in general, enzymes are the main components of viperid venoms.…”

A Wolf in Another Wolf’s Clothing: Post-Genomic Regulation Dictates Venom Profiles of Medically-Important Cryptic Kraits in India

“…Ecology and environment are well-known to influence the composition and potencies of snake venoms [ 38 , 39 , 40 , 41 , 42 ]. Differing biogeographies have been shown to have a significant impact on the venoms of Naja naja and Daboia russelii , two of the medically most important ‘big four’ snakes [ 43 , 44 , 45 , 46 , 47 , 48 , 49 ].…”