Table 1.- Variants (SNPs) included in the PRS calculation
(Disease/Trait: Atrial_fibrillation)
rsID	Risk allele	Effect size
rs2220427	T	0.535
rs2106261	T	0.282
rs3853445	T	0.285
rs12044963	T	0.104
rs1049334	G	0.185
rs17461925	A	0.074
rs13219206	C	0.135
rs13385	A	0.090
rs4766566	T	0.104
Effect size: LN(OR)

Table 2.- PRS Score distribution among populations and regions
(Disease/Trait: Atrial_fibrillation)
	count	mean	sd	se	lower.ci	upper.ci
Pyrenean regions
WEST	168	0.076	0.022	0.002	0.072	0.079
SOUTH	83	0.074	0.022	0.002	0.069	0.078
EAST	146	0.076	0.021	0.002	0.073	0.080
Populations
IBS	107	0.081	0.022	0.002	0.077	0.085
PIR	397	0.076	0.022	0.001	0.073	0.078

Table 3.- Pairwise t-test for PRS score among populations and regions
(Disease/Trait: Atrial_fibrillation)
group1	group2	n1	n2	p	p.signif	p.adj	p.adj.signif
IBS	PIR	107	397	0.0286	*	0.286	ns
IBS	WEST	107	168	0.0659	ns	0.659	ns
IBS	SOUTH	107	83	0.0266	*	0.266	ns
IBS	EAST	107	146	0.1120	ns	1.000	ns
WEST	SOUTH	168	83	0.4690	ns	1.000	ns
WEST	EAST	168	146	0.8240	ns	1.000	ns
SOUTH	EAST	83	146	0.3740	ns	1.000	ns
* p < .05, ** p < .01, *** p < .001

Table 4.- Chi-square test comparison of percentile counts on Pyrenean regions compared to Iberian peninsula population
(Disease/Trait: Atrial_fibrillation)
Percentile rank	PIR				WEST				SOUTH				EAST
	adj.std.val	p.value	sig.val		adj.std.val	p.value	sig.val		adj.std.val	p.value	sig.val		adj.std.val	p.value	sig.val
pct95	−0.360	0.719	.	white	0.250	0.803	.	white	−0.360	0.719	.	white	0.040	0.968	.	white
pct75.95	−0.740	0.459	.	white	−0.680	0.497	.	white	−0.740	0.459	.	white	−0.360	0.719	.	white
pct50.75	−0.980	0.327	.	white	−1.340	0.180	.	white	−0.980	0.327	.	white	−2.030	0.042	*
pct25.50	0.680	0.497	.	white	1.620	0.105	.	white	0.680	0.497	.	white	2.360	0.018	*
pct25	1.230	0.219	.	white	0.310	0.757	.	white	1.230	0.219	.	white	−0.010	0.992	.	white
adj.std.val: Adjusted standardized residuals value; p.value: P value; sig.val: statistical significance, * p < .05, ** p < .01, *** p < .001; red dash to bottom: lower counts than reference; green dash to up: upper counts than reference