Fig. 2: European-derived polygenic scores have reduced performance in Arabs.

a Map showing the distribution of Arab populations around the world (created using the ‘rnaturalearth’ package in R and the cited data sources)^{13, 57, 58}. b Principal components of ancestry plot showing indigenous Arabs (in dark green) in this study compared to 1000 Genomes Project populations (AFR: African (in orange); AMR: Admixed American (in yellow); EAS: East Asian (in dark blue); EUR: European (in dark red); SAS: South Asian (in violet)). c Performance of polygenic scores for coronary artery disease and type 2 diabetes in Arabs from this study vs. a matched case-control sample of European-ancestry individuals from the UK Biobank (EUR). The polygenic score for cardiomyopathy (PGS002051) has been derived in the UK Biobank where it has an inflated estimate of effect size making a comparison to Arabs inaccurate. N total is the total number of samples in the validation dataset excluding missing values for each disease. Odds ratio per standard deviation of the score is derived from a logistic regression model adjusted for age, sex, array version, and first 10 principal components of ancestry. The black boxes indicate the adjusted odds ratio. The horizontal lines around the black boxes indicate the 95% confidence intervals. d Performance of polygenic scores for LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), triglycerides (TG), systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), and height in Arabs from this study (dark green) vs. a matched case-control sample of European-ancestry individuals from the UK Biobank (EUR, dark red). Sample sizes for all traits are included in Supplementary Table 2. Effect size estimates are derived from linear regression models adjusted for age, sex, array version, and first 10 principal components of ancestry. Error bars represent the standard error.