HFE and Alzheimer disease: The lack of association between genetic variability in HFE and AD in the current study may be related to one or more of several factors: first, the present results may represent a false negative finding, driven in part by the low sample numbers; second, the role of HFE variants in risk for disease may vary between different populations (ie genetic background); third, as discussed below, the variants studied here may not be disease causing, but in linkage disequilibrium with disease causing mutations, thus discordant results will be seen in different populations.