RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISM OF MITOCHONDRIAL-DNA IN SUB-ANTARCTIC MUSSELS

Mitochondrial DNA (mtDNA) variation in samples of the marine mussel Mytilus desolationis Lamy 1936, from two localities in the Kerguelen Islands are analysed by the restriction fragment length polymorphism (RFLP) method to test for panmixia among the genetic regions previously established with enzyme polymorphism data. The results of Eco RI digestions and the reduced level of DNA polymorphism inside of the archipelago compared to oceanic coasts give evidence for the absence of panmixia. Genetic data are related to the hydrology of the archipelago. It is proposed that larvae from external oceanic coasts cannot enter the Gulf of Morbihan. In the particular context of isolation from continental masses of the Kerguelen archipelago, these results provide an opportunity to combine estimations of migration rate to those of natural selection in an island model. © 1990.