Apolipoprotein(a) (Apo(a)) is a glycoprotein that is linked by a disulfide bond to apolipoprotein B on low density lipoprotein particles to form lipoprotein(a) (Lp(a)). High plasma levels of Lp(a) are thought to contribute directly to the development of atherosclerosis. We tested a variant (T3888P) located in the Kringle-IV region of Apo(a) in a case-control series. Overall, there were no differences between case and controls. However, in the apoE2 positive subgroup, we noticed that the mutant allele is over-represented in the cases (P=0.005). We suggest that this polymorphism and others at the Apo(a) locus be further studied in relation to Alzheimer's disease.