Furthermore, ApoE genotyping available in Aβ-positive iCJD (8, 9, 10 and 27 of Table 1) and sCJD (65, 66 and 67 of Additional file 1: Table S2) cases underlined the lack of ApoE-ε4/4, and the presence of ApoE-ε3/3 in all CJD cases with the exception of one iCJD (case 8) that had genotype ApoE-ε2/3. Here, APOE is linked to Creutzfeldt Jacob disease.