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Ancient DNA of African slaves in Portugal

Publication Date: 16 September, 2014


Genetic Evidence of African Slavery at the Beginning of the Trans-Atlantic Slave Trade

Scientific Reports 4, Article number: 5994 doi:10.1038/srep05994

Received 10 April 2014 Accepted 10 July 2014 Published 08 August 2014

Authors: Rui Martiniano, Catarina Coelho, Maria Teresa Ferreira, Maria João Neves, Ron Pinhasi & Daniel G. Bradley

An archaeological excavation in Valle da Gafaria (Lagos, Portugal), revealed two contiguous burial places outside the medieval city walls, dating from the 15th–17th 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.

Read the full publication here.