Table 1.- Variants (SNPs) included in the PRS calculation
(Disease/Trait: Febrile_seizures)
rsID	Risk allele	Effect size
rs114444506	C	0.737
rs13004083	A	0.385
rs273259	A	0.351
rs1318653	T	0.392
rs3094604	A	0.329
rs2679084	T	0.621
rs3769955	T	0.199
Effect size: LN(OR)

Table 2.- PRS Score distribution among populations and regions
(Disease/Trait: Febrile_seizures)
	count	mean	sd	se	lower.ci	upper.ci
Pyrenean regions
WEST	168	0.259	0.038	0.003	0.253	0.264
SOUTH	83	0.261	0.034	0.004	0.254	0.269
EAST	146	0.252	0.040	0.003	0.246	0.259
Populations
IBS	107	0.259	0.036	0.003	0.252	0.266
PIR	397	0.257	0.038	0.002	0.253	0.261

Table 3.- Pairwise t-test for PRS score among populations and regions
(Disease/Trait: Febrile_seizures)
group1	group2	n1	n2	p	p.signif	p.adj	p.adj.signif
IBS	PIR	107	397	0.5670	ns	1.000	ns
IBS	WEST	107	168	0.9250	ns	1.000	ns
IBS	SOUTH	107	83	0.7220	ns	1.000	ns
IBS	EAST	107	146	0.1450	ns	1.000	ns
WEST	SOUTH	168	83	0.6340	ns	1.000	ns
WEST	EAST	168	146	0.1250	ns	1.000	ns
SOUTH	EAST	83	146	0.0841	ns	0.841	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: Febrile_seizures)
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	−1.130	0.258	.	white	−0.710	0.478	.	white	−1.130	0.258	.	white	−1.160	0.246	.	white
pct75.95	0.480	0.631	.	white	0.740	0.459	.	white	0.480	0.631	.	white	−0.130	0.897	.	white
pct50.75	0.580	0.562	.	white	−0.310	0.757	.	white	0.580	0.562	.	white	0.520	0.603	.	white
pct25.50	−0.790	0.430	.	white	−0.350	0.726	.	white	−0.790	0.430	.	white	−0.760	0.447	.	white
pct25	0.460	0.646	.	white	0.380	0.704	.	white	0.460	0.646	.	white	1.020	0.308	.	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