We and our Colombian colleagues have recently shown that ApoE isoforms bind to heparin sulfate with differential affinity to HSPG (ApoE 4 > 3 > 2>>Christchurch) following our observation of resistance to AD dementia in an autosomal dominant AD mutation carrier with two copies of the rare APOE4 Christchurch mutation, suggesting a possible relationship between four levels of ApoE variant binding to heparan sulfate and the risk of AD [17]. Here, APOE is linked to Alzheimer disease.