Tag: archaeology

Categories : GeneticsTags :

First DNA Study of Ancient Eastern Arabians Reveals Malaria Adaptation

On By ModernMedia
Photo by MJ RAHNAMA

People living in ancient Eastern Arabia appear to have developed resistance to malaria following the appearance of agriculture in the region around five thousand years ago, a new study published its in Cell Genomics reveals.

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 malaria.

In the present day, among the populations examined, the G6PD mutation is detected at its peak frequency in the Emirates, the study indicates.

Researchers discovered that the ancestry of Tylos-period inhabitants of Bahrain comprises sources related to ancient groups from Anatolia, the Levant and Caucasus/Iran.

The four Bahrain individuals were genetically more like present-day populations from the Levant and Iraq than to 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, as well as research centres in Europe.

Lead researcher Rui Martiniano, from Liverpool John Moores University, commented: “According to our estimates, the G6PD Mediterranean mutation rose in frequency around five-to-six thousand years ago — coinciding with the onset of agriculture in the region, which would have created ideal conditions for the proliferation of malaria.”

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

Marc Haber, from the University of Birmingham Dubai, commented: “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, states, “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 is difficult to find well-preserved sources of DNA.”

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

Researchers collected ancient human remains from archaeological collections stored at the Bahrain National Museum, gathering DNA from 25 of them. Only four samples were sequenced to higher coverage due to poor preservation.

The finding of malaria adaptation agrees with archaeological and textual evidence that suggested malaria was historically endemic in Eastern Arabia, whilst the DNA ancestry of Tylos-period inhabitants of Bahrain corroborates archaeological evidence of interactions between Bahrain and neighbouring regions.

Source: University of Birmingham

Categories : Diseases, Syndromes and Conditions PaediatricsTags :

Rickets in the Industrial Revolution Driven by Low Vitamin D

On By ModernMedia
Photo by Mayur Gala on Unsplash

Rickets ran rife in children following the Industrial Revolution, but University of Otago-led research has found factory work and polluted cities aren’t entirely to blame for the period’s vitamin D deficiencies.

In a study published in PLOS One, researchers sampled teeth from a cemetery site in industrial era England, looking for microscopic markers of nutritional disease.

Lead author Dr Annie Sohler-Snoddy, Research Fellow in Otago’s Department of Anatomy, says they uncovered some of the first clear evidence of seasonal vitamin D deficiency in an archaeological sample.

She says it has been known for many years that there was an increase in rickets, a childhood bone disease caused by vitamin D deficiency, in 18th and 19th Century Europe.

“It has been assumed that this was due to more people, including children, working long hours indoors, living in crowded housing and in smog-filled environments, all of which reduce the amount of sunlight that reaches a person’s skin, which is the main way humans make vitamin D.”

However, new bioarchaeological methods enabled the researchers to get a much clearer picture of how vitamin D deficiency affected the people living in industrial England, rather than looking at bone deformities alone.

The study, from Otago, Durham University, University of Edinburgh, University of Brighton, and University of Queensland, found markers associated with vitamin D deficiency in the interior part of 76% of the teeth analysed.

In many samples, these occurred regularly, in annual increments.

“This shows clear evidence of seasonal vitamin D deficiency in the teeth of people living in the north of England.

“This is exciting because it highlights that latitude and seasonal lack of sunlight was a major factor in the amount of vitamin D these people could make in their skin – it’s more complicated than the factors associated with the industrial revolution like working indoors more,” Dr Sohler-Snoddy explains.

Poor vitamin D status is associated with several negative health outcomes including increased risk for infectious diseases, cardiovascular disease, and cancers.

Vitamin D deficiency has been an ongoing problem in society and Dr Sohler-Snoddy believes it is important to study what happened in the past in order to inform modern approaches to the ailment.

“We tend to think of archaeological human remains as belonging to a different world, but our biology hasn’t changed in the last 200 years.

“Teeth provide a really important source of information for archaeologists as they form in a very precise chronology and, importantly, their tissues do not change over the lifespan. This means that they lock in a record of a person’s development and this stays with them until they die, or the tooth is lost.

“Understanding how vitamin D deficiency impacted past populations and why gives us an important deep-time perspective on the disease,” she says.

Source: University of Otago