The genomes of enslaved Africans who died on the remote Atlantic island of St Helena in the mid-19th century are offering clues about their origins, in addition to insights into the transatlantic slave trade which saw an estimated 12 million Africans kidnapped and enslaved.

Researchers from the University of Copenhagen analysed the remains of 20 of the people who were buried on the island and identified probable links to parts of west-central Africa, including present-day Angola and Gabon, the journal Nature reports.

However, it is not yet possible to find the precise origins of people trafficked in the transatlantic slave trade, because of gaps in genome databases of people living in Africa today.

After Britain outlawed the slave trade in 1807, its navy intercepted slave ships mainly bound for Brazil and Cuba before sending around 24,000 rescued people to St Helena. Many were in poor health and thousands died on the island.

The research team, led by palaeogenomicist Marcela Sandoval-Velasco and ancient-DNA researcher Hannes Schroeder, found that none of the people whose remains they analysed were from a particular population and for this reason may not have understood each other’s language and customs.

St Helena’s government plans to rebury all the remains where they were first uncovered and to create a memorial at the site.