Single nucleotide polymorphisms of SORL1 reported in literature as being associated with AD were investigated in an Italian case-control data set, and their role as a risk factor of conversion to AD was studied in an independent sample of subjects diagnosed with mild cognitive impairment (MCI) at baseline. rs641120, rs2070045, and rs1010159 were genotyped in 734 subjects diagnosed with AD (n = 338) and MCI (n = 181) and in healthy controls (n = 215).