2Author for correspondence: e-mail email@example.com.
MICROSATELLITE MARKERS REVEAL POPULATION GENETIC STRUCTURE OF THE TOXIC DINOFLAGELLATE ALEXANDRIUM TAMARENSE (DINOPHYCEAE) IN JAPANESE COASTAL WATERS1
Version of Record online: 16 FEB 2007
Journal of Phycology
Volume 43, Issue 1, pages 43–54, February 2007
How to Cite
Nagai, S., Lian, C., Yamaguchi, S., Hamaguchi, M., Matsuyama, Y., Itakura, S., Shimada, H., Kaga, S., Yamauchi, H., Sonda, Y., Nishikawa, T., Kim, C.-H. and Hogetsu, T. (2007), MICROSATELLITE MARKERS REVEAL POPULATION GENETIC STRUCTURE OF THE TOXIC DINOFLAGELLATE ALEXANDRIUM TAMARENSE (DINOPHYCEAE) IN JAPANESE COASTAL WATERS. Journal of Phycology, 43: 43–54. doi: 10.1111/j.1529-8817.2006.00304.x
1Received 4 April 2006. Accepted 21 September 2006.
- Issue online: 16 FEB 2007
- Version of Record online: 16 FEB 2007
- Alexandrium tamarense;
- gene flow;
- genetic distance;
- genetic structure;
- human-assisted dispersal;
- paralytic shellfish poisoning;
- population differentiation
This is the first report to explore the fine-scale diversity, population genetic structure, and biogeography of a typical planktonic microbe in Japanese and Korean coastal waters and also to try to detect the impact of natural and human-assisted dispersals on the genetic structure and gene flow in a toxic dinoflagellate species. Here we present the genetic analysis of Alexandrium tamarense (Lebour) Balech populations from 10 sites along the Japanese and Korean coasts. We used nine microsatellite loci, which varied widely in number of alleles and gene diversity across populations. The analysis revealed that Nei's genetic distance correlated significantly with geographic distance in pair-wise comparisons, and that there was genetic differentiation in about half of 45 pair-wise populations. These results clearly indicate genetic isolation among populations according to geographic distance and restricted gene flow via natural dispersal through tidal currents among the populations. On the other hand, high P-values in Fisher's combined test were detected in five pair-wise populations, suggesting similar genetic structure and a close genetic relationship between the populations. These findings suggest that the genetic structure of Japanese A. tamarense populations has been disturbed, possibly by human-assisted dispersal, which has resulted in gene flow between geographically separated populations.