A report from ICAD 2016 (page 4 and page 9 of below pdf) suggests that protection to Alzheimer's disease might be offered by two variants.
rs142787485 (p=0.018 OR=0.58) and rs7653 (p=0.0049. OR=0.35, not subsequently validated) were found to be protective in a pedigree
analysis and WES series. Validation was performed in 4 independent case control samples. The Mayo Series, though, did not find significant
association for rs142787485.
rs142787485 is in the Rab10 gene which was shown to be involved in the regulation of amyloid beta.