Objectives: The apolipoprotein E (apoE) polymorphism, designated as epsilon2, epsilon3, epsilon4, is a genetic risk factor associated with several forms of dementia. Inconclusive results have been reported in patients with frontotemporal degeneration which prompted this study of the apoE polymorphism in a German sample with frontotemporal degeneration.
Methods: the frequencies of the epsilon2 and epsilon4 alleles and the effect of these alleles on the age at onset in 52 patients with frontotemporal degeneration who underwent a thorough diagnostic examination and in 182 cognitively healthy age matched controls were assessed. Genotype comparisons between the groups were performed using multiple logistic regression analysis. Ages at onset according to the apoE genotype were compared by linear regression analysis.
Results: In patients with frontotemporal degeneration apoE epsilon2 and epsilon4 allele frequencies were 9.6% each, whereas the corresponding frequencies in controls were 9.6% and 9.9%, respectively. There was no significant difference in either epsilon2 or epsilon4 allele frequency between the groups. Age at onset was highest in patients with the epsilon2/epsilon3 genotype (61.3 years) followed by patients with the epsilon3/epsilon3 (58.3 years) and was lowest in patients with the epsilon3/epsilon4 genotype (56.4 years) but the differences failed to reach statistical significance.
Conclusion: Allelic variants of the apoE gene do not modulate occurrence or age at onset in this sample of German patients with frontotemporal degeneration.