WCM-Q research seeks to translate benefits of personalized medicine from European to Arab populations

Researchers at Weill Cornell Medicine-Qatar (WCM-Q) have analyzed vast amounts of genetic and protein-related data to determine the effectiveness of genetics-based personalized medicine for Arabs.

While personalized medicine holds huge potential for assessing disease risk for individuals, a weakness of the science is its reliance on genetic data that have been drawn largely from populations with European/Caucasian ancestry.

This is because physicians use large, population-wide genetic datasets to identify genes associated with diseases, which they then compare with the genetic information of individuals. This information is then combined with other factors, such as environment and lifestyle, to generate a ‘polygenic risk score’ for chronic conditions such as heart disease, cancer and dementia, which can then guide how healthcare is administered. But natural genetic variability between ethnic groups means that identification of genetic-based disease is more difficult for individuals whose ethnicity differs from that of the majority of individuals in the dataset.

Researchers at WCM-Q, led by Dr. Karsten Suhre, set out to quantify the disparity in accuracy of polygenic scores between populations of European and Arab ancestry. Dr. Suhre, professor of physiology and biophysics/director of bioinformatics core at WCM-Q said: “We are lucky to have good quality genetic data from a large number of people, but the level of ethnic diversity in these datasets is quite low and very much focused on populations with European ancestry - this poses challenges for personalized medicine in understudied populations. We therefore wanted to be able to determine accurately how much or how little confidence we can have in polygenic risk scores generated for Arabs from comparisons made with genomic data gathered mainly from Caucasian populations.”

To make the comparison, the researchers analyzed 2,935 blood samples from individuals of Arabic ancestry, stored in Qatar Biobank, to examine their genomes and the genetic architecture of a set of 1,301 proteins known to be associated with numerous diseases. Proteins are considered a useful target for investigation because they are intermediate traits that link genetic predisposition and environmental factors to disease. The process is known as a ‘genome-wide association study’ because it analyzes the entire genome of each individual, which comprises all of the data from every one of their genes.

The researchers then compared the association between genetic traits and disease-linked proteins in the Arab population with the same associations in European/Caucasian populations. After analyzing all of the data, the research team concluded that protein-based polygenic risk scores are approximately 20 percent more accurate for Europeans when compared to Arabs. Other WCM-Q researchers who worked on the paper were senior bioinformatics data specialist Gaurav Thareja (first author of the paper), research associate Dr. Aziz Belkadi, and Dr. Frank Schmidt, director of the proteomics core and associate professor of biochemistry. The paper, titled, ‘Differences and commonalities in the genetic architecture of protein quantitative trait loci in European and Arab populations,’ has been published in Human Molecular Genetics, a leading journal. Researchers at Weill Cornell Medicine in New York, Hamad Bin Khalifa University, Duke University, the University of Edinburgh, Philipps-Universität Marburg in Germany, and the German Research Center for Environmental Health, among other institutions, also contributed.

Dr. Suhre, who also holds the position of assistant dean for intercampus research partnerships at WCM-Q, added: “The data shows us that polygenic scores are still useful for identifying disease risk for Arab populations but that more research and sample gathering is needed if we wish to extend the full benefits of this new technology to lesser studied populations.”

The study was supported by the Biomedical Research Program at Weill Cornell Medicine in Qatar, a program funded by the Qatar Foundation, and by grant NPRP11C-0115-180010, PPM 03-0324-19003 and NPRP12S-0227-190173 from Qatar National Research Fund (a member of Qatar Foundation).

Dr. Suhre has external relationships with Alpha Biomics Ltd., Valdia Health, and the World Anti-Doping Agency.