Mende

English is his third language after Krio and Mende—all of which are spoken in his native Sierra Leone.

"On the other, it also enables the cell to meet its need for important building blocks, including in the event of a nutrient deficiency or increased cell proliferation, which is characteristic of cancer cells," explains PhD student Hannah Mende, the study's first author.

These included: 85 individuals from a West African group called the Mende from Sierra Leone; 44 individuals from the Nama Khoe-San group from southern Africa; 46 individuals from the Amhara and Oromo groups in Ethiopia; and 23 individuals from the Gumuz group, also from Ethiopia.

The researchers analyzed DNA from a range of African groups, including the Mende, farmers who live in Sierra Leone in West Africa; the Gumuz, a group descended from hunter-gatherers in Ethiopia; the Amhara, a group of Ethiopian farmers; and the Nama, a group of hunter-gatherers in South Africa.

The DNA of the Mende people showed that their ancestors had interbred with Stem2 people just 25,000 years ago.