NE Atlantic corals
Other molecular techniques can be used to investigate deep-sea coral populations at different geographical scales. Lophelia samples collected in Scandinavian fjords appeared to be genetically different from those distributed along the European continental margin. Results also suggest that continental margin reefs might originate from migrants dispersed out of the fjords in the past.
By using very variable molecular markers called micro-satellites, it is possible to gain very high resolution information about coral populations, even at the scale of a particular reef, about genetic diversity, larval exchanges among reefs and the levels of sexual and asexual reproduction. Such investigations revealed very varied profiles of populations across the NE Atlantic with some populations showing much higher genetic diversity, while others showed a much higher proportion of asexual than sexual reproduction.
On a wider-scale, larval dispersal seemed to be restricted locally around reefs, even if sporadic dispersal could occur between the continental margin populations. Fjord populations appeared very distinct from one another and from the continental margin populations.