The Qatar Genome Research Consortium has published an in-depth analysis of more than 6000 whole genomes from Qatar, which the researchers hope will bring new insights for treating and diagnosing disease as well as shedding light on the history of population movements in the area.
Genomic studies to date have largely focused on people of white European ancestry, which can be problematic as new clinical tools such as polygenic risk scores are then less accurate in non-white populations.
There is little available genomic data from the Middle-East and populations in or from these areas. Including 6,218 Qatari genomes, this study presents the biggest dataset from this area so far.
The researchers carried out an in-depth analysis of the genomes looking for both health and genealogical markers, which was published in the journal Nature Communications.
Commenting in a press statement, Asmaa Althani, a professor at Hamad Bin Khalifa University, and Chair of the National Genome Qatar Committee said: “As producers of the largest genomic dataset in the region, we hold a responsibility… to represent our part of the world and fill many of the existing knowledge gaps on genomics of the Middle Eastern populations. This paper is a great example of the role that we play.”
From a medical perspective, this kind of data is very useful as it can show which disease-related variants are common or rare in different populations and can help improve the statistical power of genetic tests carried out to gauge future risk from diseases like cancer. Althani and colleagues have used the data to build a reference panel to impute genetic variation, which is the first one created solely for Arab populations.
This is particularly relevant as they found very high rates of homozygosity in the population, which suggests that novel disease risk genes may be present in this population group.
The researchers are based both at Hamad Bin Khalifa University and at Sidra Medicine, an academic research center in Qatar with a focus on implementing precision medicine in the Middle East. In addition to collecting data that can help implement precision medicine in the region, they also uncovered some interesting historical markers in the population by studying Y chromosome and mitochondrial DNA of the participants.
“Despite the relatively small size of the Qatari population, we discovered diverse ancestries relating to Europe, Asia, Africa and even South America. Notably we found a unique group of Peninsular Arabs as the most ancient of all modern Middle Eastern populations. This provides a fantastic addition to our knowledge of human genetic diversity,” commented Younes Mokrab, a principal investigator at Sidra Medicine and co-lead author of the study.
They found there was a population split from early Africans around 90,000 years ago and a split 30–42,000 years ago that preceded the formation of distinct Arab, European, and South Asian populations. There were also several population splits 12–20,000 years ago during the aridification of Arabia.
“The value of this resource will expand in the upcoming phases of Qatar Genome Program as tens of thousands of additional subjects will be sequenced over the next few years, enabling vital future genomic and medical research in the Middle East and globally,” conclude the authors.