we sought to identify new susceptibility loci for alzheimer s disease ( ad ) through a staged association study ( gerad+ ) and by testing suggestive loci reported by the alzheimer s disease genetic consortium ( adgc ) . 
 first , we undertook a combined analysis of four genome - wide association datasets ( stage 1 ) and identified 10 novel variants with p1105 . 
 these were tested for association in an independent sample ( stage 2 ) . 
 three snps at two loci replicated and showed evidence for association in a further sample ( stage 3 ) . 
 meta - analyses of all data provide compelling evidence that abca7 ( meta - p 4.51017 ; including adgc meta - p=5.01021 ) and the ms4a gene cluster ( rs610932 , meta - p=1.81014 ; including adgc meta - p=1.21016 ; rs670139 , meta - p=1.4109 ; including adgc meta - p=1.11010 ) are novel susceptibility loci for ad . 
 second , we observed independent evidence for association for three suggestive loci reported by the adgc gwas , which when combined shows genome - wide significance : cd2ap ( gerad+ p=8.0104 ; including adgc meta - p=8.6109 ) , cd33 ( gerad+ p=2.2104 ; including adgc meta - p=1.6109 ) and epha1 ( gerad+ p=3.4104 ; including adgc meta - p=6.01010 ) . 
 these findings support five novel susceptibility genes for ad .