The -491 A/T polymorphism in the regulatory region of the Apolipoprotein Egene and early-onset Alzheimer's disease

The -491 polymorphism in the promoter region of the apolipoprotein E gene ( APOE) has been suggested to be associated with increased risk for Alzheimer 's disease (AD) independent of APOE status. We studied the association betw een the -491 polymorphism and risk for early-onset Alzheimer's disease in 9 9 Dutch and 78 Spanish patients. In patients with early-onset AD, we found no consistent relationship with a single allele of the -491 polymorphism. L inkage disequilibrium between the polymorphism and the APOE gene was found which most likely might explain the inconsistent findings. (C) 1998 Elsevie r Science Ireland Ltd. All rights reserved.