Genetic Diversity in the Lesser Antilles and Its Implications for the Settlement of the Caribbean Basin

Abstract

Historical discourses about the Caribbean often chronicle West African and European influence to the general neglect of indigenous people's contributions to the contemporary region. Consequently, demographic histories of Caribbean people prior to and after European contact are not well understood. Although archeological evidence suggests that the Lesser Antilles were populated in a series of northward and eastern migratory waves, many questions remain regarding the relationship of the Caribbean migrants to other indigenous people of South and Central America and changes to the demography of indigenous communities post-European contact. To explore these issues, we analyzed mitochondrial DNA and Y-chromosome diversity in 12 unrelated individuals from the First Peoples Community in Arima, Trinidad, and 43 unrelated Garifuna individuals residing in St. Vincent. In this community-sanctioned research, we detected maternal indigenous ancestry in 42% of the participants, with the remainder having haplotypes indicative of African and South Asian maternal ancestry. Analysis of Y-chromosome variation revealed paternal indigenous American ancestry indicated by the presence of haplogroup Q-M3 in 28% of the male participants from both communities, with the remainder possessing either African or European haplogroups. This finding is the first report of indigenous American paternal ancestry among indigenous populations in this region of the Caribbean. Overall, this study illustrates the role of the region's first peoples in shaping the genetic diversity seen in contemporary Caribbean populations.

Fig 1. A map of the Lesser Antilles showing the locations of St. Vincent and the Grenadines and Trinidad and Tobago.

Fig 2. A MDS plot of FST estimates based on mtDNA HVS1 sequences (np 16024–16400) for Indigenous Caribbean and comparative Central and South American populations.

The stress value of the plot is 9.8%. Data points are labeled with the population name and color-coded by geographic origin, with each shape corresponds to the language family of the sample.

Fig 3. A MDS plot of FST estimates based on mtDNA HVS1 sequences (np 16109–16393) for Indigenous Caribbean and comparative Anglophone Caribbean populations.

The stress value of the plot is 0.2%.

Fig 4. A median-joining network of mtDNA haplogroup A2 haplotypes (np16024-16400) from Indigenous Caribbean and comparative Central and South American populations.

Populations represented in each node of the network are shown in different colors.

Fig 5. A median-joining network of mtDNA haplogroup C1 haplotypes (np16024-16400) from indigenous Caribbean and comparative Central and South American populations.

Populations represented in each node of the network are shown in different colors.

Fig 6. A MDS plot of RST estimates based on Y-STR haplotypes for Indigenous Caribbean and comparative Central and South American populations.

The stress value of the plot is 8.7%.

Fig 7. A median-joining network of Y-chromosome Q-M3 STR haplotypes from Indigenous Caribbean and comparative Central and South American populations.

Populations represented in each node of the network are shown in different colors.