CD33 and early-onset autosomal dominant Alzheimer disease: Given the modest blood cell phenotype observed from the PBMCs collected from the PGR recall study along with previous publications indicating that CD33 may play a role in susceptibility to Alzheimer’s disease and isolated leukemias, a subset of 31 continuous phenotypes and 13 binary outcomes related to hematological clinical endpoints as well as neurological disease were evaluated for association with CD33 LOF in the large whole exome dataset available through UK Biobank.