image: The Tiger Rattlesnake (Crotalus tigris) possesses a highly neurotoxic, simple venom, that feeds on small mammals and lizards. Santa Catalina Mountains, Pima County, AZ, USA. view more
Credit: Image credit: Wolfgang Wüster (Bangor University, Bangor, UK)
对虎斑响尾蛇的简单但是高度毒性的毒液的生产背后的遗传变异的一项研究发现，毒液基因的数量极大地超过了毒液蛋白质的数量，这提示遗传调控机制而非基因数量或序列，在很大程度上造就了这种响尾蛇毒液。
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