Genetic relatedness and variability in inbred and wild populations of the solitary ascidian Ciona intestinalis revealed by arbitrarily primed polymerase chain reaction

As the first step in the establishment of inbred Ciona intestinalis strains , the genetic backgrounds of several local populations were evaluated on th e basis of comparing 313 random amplified polymorphic DNA (RAPD) loci. Clus ter analyses of individuals indicated that this species has local genetic c haracteristics, although various generic distances among the populations we re relatively low. The bulked RAPD analyses revealed that populations from Torihama and from Onagawa were the most distantly related among the 7 popul ations examined, suggesting that these two populations are the best candida tes for outbreeding. Successive inbreeding in the laboratory was achieved u sing the Onagawa population. Although the genetic similarity of the F-4 pro geny became distinctly higher than that of natural populations, F-5 progeny did not survive, presumably owing to homozygous lethal alleles.