Snake toxins belong to a family of proteins [1,2,3] which groups short and long neurotoxins, cytotoxins and short toxins, as well as a other miscellanous venom peptides. Most of these toxins act by binding to the nicotinic acetylcholine receptors in the postsynaptic membrane of skeletal muscles and prevent the binding of acetylcholine, thereby blocking the excitation of muscles. Snake toxins are proteins that consist of sixty to seventy five amino acids. Among the invariant residues are eight cysteines all involved in disulfide bonds. A signature pattern was developed [4] which includes four of these cysteines as well as a conserved proline thought to be important for the maintenance of the tertiary structure. The second cysteine in the pattern is linked to the third one by a disulfide bond. Consensus pattern: G-C-x(1,3)-C-P-x(8,10)-C-C-x(2)-[PDEN] [The four C's are involved in disulfide bonds] Sequences known to belong to this class detected by the pattern: Most of thesnake toxins are detected except for fasciatoxin, which is an atypical short neurotoxin, and eight toxins which have a very low activity.