Abstract
The interactions host-parasite between mollusks and trématodes are characterized by a polymorphism of compatibility which shows itself by the presence of compatible couples (susceptible host and/or virulent parasite) and of incompatible couples (resistant host and/or parasite avirulent) in natural populations. To arrest(dread) the molecular determiners responsible for this differential compatibility between the mollusk Biomphalaria glabrata and the trématode parasite Echinostoma caproni, several comparative molecular studies were realized on two origins(stumps) of B. Glabrata, susceptible and resistant in E. Caproni. Previous works having highlighted the differences plasmatiques and hémocytaires between these origins(stumps), our molecular approaches were led in the first one