Abstract
Abstract: Genetical differences were examined among three geographically different populations of a lancelet, Branchiostoma belcheri in western Japan. Electrophoresis of PCR products with six different primers detected 13-19 DNA bands from sixteen individuals of these three populations. Among them, two bands were common to all individuals, and three bands were shared with the populations of Hiroshima Bay and the Sea of Genkai. One band was specific to the population of the Sea of Genkai, and three bands were specific to the population of Osaka Bay. In cluster analysis on the genetic similarity, the individuals collected at the Sea of Genkai are relatively close to those of Hiroshima Bay, but both populations are relatively distant from those of Osaka Bay. It might be inferred that the three populations have not originated from a common larval recruitment and there are no genetical exchanges via larval recruitment at least between the populations of Hiroshima Bay and Osaka Bay.
