|Jamaican slave revolt of 1759 (source)|
There is a new study on the mitochondrial DNA of Jamaicans, shedding some light on the ancestry of this Caribbean nation:
Michael L. Deason et al., Interdisciplinary approach to the demography of Jamaica. BMC Evolutionary Biology 2012. Open access.
I must certainly commend the historical introduction, which is not just comprehensive but also easy to follow and understand and well integrated with the information provided by the mitochondrial DNA findings.
While there are a handful of lineages rooted in Native America or North of the Sahara (but not European), the overwhelming majority of the more than 400 Jamaican matrilineages studied in their HVS-I region have their roots in Africa.
The most informative findings are however those about the regional origins within Africa of the ancestors of modern Jamaicans. The Gold Coast and Bight of Benin regions (between Assini and the Niger Delta per fig. 1) are the main sources of Jamaican ancestry. Other West African regions (Sierra Leone, Bight of Biafra and West-Central Africa) were secondary sources only, while South and East Africa is almost not represented.
This last appears to have surprised the authors, who expected more impact of the late slave trade based largely on the Indian Ocean coasts, similarly they seem a bit perplex by the relatively low influence of the Bight of Biafra, another major late source of African slaves. They argue that greater traveled distances may have hurt the chances of survival of people being transported from farther away (a documented fact) and that creole slaves, those born in the Caribbean, had much better chances of survival and even some chances of upward mobility.
See also: African ancestry of the Noir Marron of the Guianas, a previous example of the same approach cited in this paper. In that case however the bulk of the ancestry was from the Biafra area.