DNA study of ancient Eastern Arabians reveals protection against malaria

Science and Health

People living in ancient Eastern Arabia apparently became resistant to malaria after they began to farm in the region about 5,000 years ago. A DNA analysis of the remains of four individuals from Tylos-period Bahrain (300 BCE to 600 CE), the first ancient genomes from Eastern Arabia, revealed the malaria-protective G6PD Mediterranean mutation in three samples.

The discovery of the G6PD Mediterranean mutation in ancient Bahrainis suggests that many people in the region’s ancient populations may have enjoyed protection from the infectious, deadly disease. Today, among the populations examined, the G6PD mutation is detected at its peak frequency in the Emirates, the study showed.

Researchers discovered that the ancestry of Tylos-period inhabitants of Bahrain comprises sources related to ancient groups from Anatolia, the Levant, and the Caucasus/Iran. The four Bahrain individuals were genetically more like present-day populations from the Levant and Iraq than Arabians.

Experts from Liverpool John Moores University, the University of Birmingham-Dubai, and the University of Cambridge worked with the Bahrain Authority for Culture and Antiquities and other Arabian institutes, such as the Mohammed Bin Rashid University of Medicine and Health Sciences- Dubai, along with research centers in Europe, including Université Lumière Lyon 2, Trinity College-Dublin, and others. The group has just published its findings in the journal Cell Genomics under the title “Ancient genomes illuminate Eastern Arabian population history and adaptation against malaria.”

Malaria mosquito. [File] (credit: Wikimedia Commons)

Lead researcher Rui Martiniano from Liverpool John Moores University commented: “According to our estimates, the G6PD Mediterranean mutation rose in frequency around 5,000-6,000 years ago, coinciding with the onset of agriculture in the region that would have created ideal conditions for the spread of malaria.”

Due to poor ancient DNA preservation in hot, humid climates, no ancient DNA from Arabia has been sequenced until now, which has prevented the direct examination of the genetic ancestry of its past populations.

Study offers ‘unprecedented insights into human history’

Marc Haber from the University of Birmingham-Dubai explained: “By obtaining the first ancient genomes from Eastern Arabia, we provide unprecedented insights into human history and disease progression in this region. This knowledge goes beyond historical understanding, providing predictive capabilities for disease susceptibility, spread, and treatment, thus promoting better health outcomes.”

“The rich population history of Bahrain and, more generally, of Arabia has been severely understudied from a genetic perspective. We provide the first genetic snapshot of past Arabian populations, obtaining important insights about malaria adaptation, which was historically endemic in the region,” commented Fatima Aloraifi from the Mersey and West Lancashire NHS Trust.

Salman Almahari, director of antiquities and museums at the Bahrain Authority for Culture and Antiquities, said: “Our study also paves the way for future research that will shed light on human population movements in Arabia and other regions with harsh climates where it’s difficult to find well-preserved sources of DNA.”

Data gathered from the analysis of the four individuals’ remains allowed researchers to characterize the genetic composition of the region’s pre-Islamic inhabitants – insights that could have been obtained only by directly examining ancient DNA sequences.

Researchers collected ancient human remains from archaeological collections stored at the Bahrain National Museum, extracting DNA from 25 individuals, but only four were sequenced for higher coverage due to poor preservation.

Richard Durbin of the University of Cambridge, who supervised the project, said, “It’s exciting to have been able to analyze ancient human genetic data from the remarkable burial mounds of Bahrain.”

The finding of malaria adaptation backs up archaeological and textual evidence that suggested malaria was historically endemic in Eastern Arabia, while the DNA ancestry of Tylos-period inhabitants of Bahrain corroborates archaeological evidence of interactions between Bahrain and neighboring regions.

The University of Birmingham is ranked among the world’s top 100 institutions. Its work brings people from across the world to Birmingham, including researchers, teachers, and more than 8,000 international students from over 150 countries. The university opened its doors to students in Dubai in 2018 and launched its iconic campus in 2022.