Supplementary Table 1.

Sample characteristics by geographical region

Region	Subjects	Age subsets			Sex ratio		APOEε4
		< 75 years	> 75 years	Totals	% women	p (controls vs AD)	Frequency	p (controls vs AD)
North Europe	Controls	2426	3342	5768	56.8%	0.02	13.9%*	< 0.0001
	AD	336	868	1204	60.5%		33.3%
North Spain	Controls	179	347	526	67.2%	0.90	8.3%*	< 0.0001
	AD	182	371	553	66.7%		26.0%
Totals	Controls	2605	3689	6294	57.7%	0.0004	13.4%	< 0.0001
	AD	518	1239	1757	62.4%		31.1%

AD = Alzheimer’s Disease; APOEε4 = the ε4 allele of the apolipoprotein E gene. Quality control of genotyping reduced the numbers below the above figures (see Table 3). Fuller details, including characteristics of each of the seven sample-sets, are given in Combarros et al 2009 (Combarros et al., 2009).

^*Difference between North Europe and North Spain: p < 0.0001.