MAPT and Alzheimer disease: Moreover, a correlation among the SNP (−413)TT and the development of AD has been pointed out in subjects carrying also the tau (5′ of exon 1)AA polymorphism [47] or in combination with SNPs in liver X receptor β (LXR β) such as (intron2)TT, (intron 5)AA and (intron 7)TT [48].