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Genetic evidence of African slavery at the beginning of the trans-Atlantic slave trade.

Martiniano R, Coelho C, Ferreira MT, Neves MJ, Pinhasi R, Bradley DG - Sci Rep (2014)

Bottom Line: The Leprosarium site samples were less preserved but gave some probability of both African and European ancestry.The two discard deposit burials each gave African affinity signals, which were further refined toward modern West African or Bantu genotyped samples.These data from distressed burials illustrate an African contribution to a low status stratum of Lagos society at a time when this port became a hub of the European trade in African slaves which formed a precursor to the transatlantic transfer of millions.

View Article: PubMed Central - PubMed

Affiliation: Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland.

ABSTRACT
An archaeological excavation in Valle da Gafaria (Lagos, Portugal), revealed two contiguous burial places outside the medieval city walls, dating from the 15(th)-17(th) centuries AD: one was interpreted as a Leprosarium cemetery and the second as an urban discard deposit, where signs of violent, unceremonious burials suggested that these remains may belong to slaves captured in Africa by the Portuguese. We obtained random short autosomal sequence reads from seven individuals: two from the latter site and five from the Leprosarium and used these to call SNP identities and estimate ancestral affinities with modern reference data. The Leprosarium site samples were less preserved but gave some probability of both African and European ancestry. The two discard deposit burials each gave African affinity signals, which were further refined toward modern West African or Bantu genotyped samples. These data from distressed burials illustrate an African contribution to a low status stratum of Lagos society at a time when this port became a hub of the European trade in African slaves which formed a precursor to the transatlantic transfer of millions.

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Related in: MedlinePlus

Comparison of Cytosine Deamination patterns in the 5′ end of sequencing reads between the samples from the Leprosarium (yellow dotted lines) and UDD (red dotted lines) burial sites with a ~5,000 year old Scandinavian hunter-gatherer and a 100 year old Australian Aboriginal.The range of C to T changes suggest the authenticity of the data.
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f1: Comparison of Cytosine Deamination patterns in the 5′ end of sequencing reads between the samples from the Leprosarium (yellow dotted lines) and UDD (red dotted lines) burial sites with a ~5,000 year old Scandinavian hunter-gatherer and a 100 year old Australian Aboriginal.The range of C to T changes suggest the authenticity of the data.

Mentions: Cytosine deamination at the 5′-end of DNA fragments (leading to C to T changes) is a signal of postmortem chemical degradation suggesting authenticity in ancient DNA sequence6 and has been shown to increase with time7. We used PMDtools8 to examine these changes in our samples and compared patterns with those present in published data (Figure 1). Cytosine deamination values observed across all samples are intermediate (0.8–0.15) when compared to the very low (0.02) and very high (0.26) fraction of C->T changes respectively in a 100 year old Australian aboriginal9 and a 5,000 year old Neolithic Scandinavian10, as would be expected from the age estimations for this burial site. The mean fraction of reads containing cytosine deamination appears to be slightly lower for the two high endogenous DNA samples belonging to the UDD site (0.09) than that within reads from the five moderately preserved Leprosarium samples (0.12).


Genetic evidence of African slavery at the beginning of the trans-Atlantic slave trade.

Martiniano R, Coelho C, Ferreira MT, Neves MJ, Pinhasi R, Bradley DG - Sci Rep (2014)

Comparison of Cytosine Deamination patterns in the 5′ end of sequencing reads between the samples from the Leprosarium (yellow dotted lines) and UDD (red dotted lines) burial sites with a ~5,000 year old Scandinavian hunter-gatherer and a 100 year old Australian Aboriginal.The range of C to T changes suggest the authenticity of the data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4125989&req=5

f1: Comparison of Cytosine Deamination patterns in the 5′ end of sequencing reads between the samples from the Leprosarium (yellow dotted lines) and UDD (red dotted lines) burial sites with a ~5,000 year old Scandinavian hunter-gatherer and a 100 year old Australian Aboriginal.The range of C to T changes suggest the authenticity of the data.
Mentions: Cytosine deamination at the 5′-end of DNA fragments (leading to C to T changes) is a signal of postmortem chemical degradation suggesting authenticity in ancient DNA sequence6 and has been shown to increase with time7. We used PMDtools8 to examine these changes in our samples and compared patterns with those present in published data (Figure 1). Cytosine deamination values observed across all samples are intermediate (0.8–0.15) when compared to the very low (0.02) and very high (0.26) fraction of C->T changes respectively in a 100 year old Australian aboriginal9 and a 5,000 year old Neolithic Scandinavian10, as would be expected from the age estimations for this burial site. The mean fraction of reads containing cytosine deamination appears to be slightly lower for the two high endogenous DNA samples belonging to the UDD site (0.09) than that within reads from the five moderately preserved Leprosarium samples (0.12).

Bottom Line: The Leprosarium site samples were less preserved but gave some probability of both African and European ancestry.The two discard deposit burials each gave African affinity signals, which were further refined toward modern West African or Bantu genotyped samples.These data from distressed burials illustrate an African contribution to a low status stratum of Lagos society at a time when this port became a hub of the European trade in African slaves which formed a precursor to the transatlantic transfer of millions.

View Article: PubMed Central - PubMed

Affiliation: Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland.

ABSTRACT
An archaeological excavation in Valle da Gafaria (Lagos, Portugal), revealed two contiguous burial places outside the medieval city walls, dating from the 15(th)-17(th) centuries AD: one was interpreted as a Leprosarium cemetery and the second as an urban discard deposit, where signs of violent, unceremonious burials suggested that these remains may belong to slaves captured in Africa by the Portuguese. We obtained random short autosomal sequence reads from seven individuals: two from the latter site and five from the Leprosarium and used these to call SNP identities and estimate ancestral affinities with modern reference data. The Leprosarium site samples were less preserved but gave some probability of both African and European ancestry. The two discard deposit burials each gave African affinity signals, which were further refined toward modern West African or Bantu genotyped samples. These data from distressed burials illustrate an African contribution to a low status stratum of Lagos society at a time when this port became a hub of the European trade in African slaves which formed a precursor to the transatlantic transfer of millions.

Show MeSH
Related in: MedlinePlus