Extended Data Fig. 7: Polygenic risk scores.
Polygenic risk scores (PRS) for 16 complex human traits in 148 Viking Age samples from Denmark, Sweden and Norway, compared against a reference sample of 20,551 Danish-ancestry individuals randomly drawn from all individuals born in Denmark in 1981–2005. The PRS is in each case based on allelic effects for >100 independent genome-wide significant SNPs from recent genome-wide association studies of the respective traits and standardised to a mean of 0 and standard deviation of 1 in the entire sample. Difference in PRS was estimated in a linear regression correcting for sex and 25 principal components of overall genetic structure. The plotted BETA indicates the coefficient for the test-group (Viking Age sample) PRS compared to that of the Danish comparison sample, with error bars indicating the 95% confidence interval of BETA, and P indicating the two-tailed P value of the corresponding t-test (not corrected for number of tests). Only PRS for black hair colour is significantly different between the groups after taking account of multiple testing.
