Lack of association between alpha1-antichymotrypsin polymorphism and late-onset depressive disorder

Late-onset depressive disorder (LOD) has been thought to be associated with dementia. Recently, it was reported that the position-15 (alanine) polymorphism of the alpha1-antichymotrypsin gene (ACT*A) was a risk factor for Alzheimer's disease. We wondered whether the ACT*A allele frequency might be elevated in LOD. ACT genotyping was performed as described by Kamboh et al. (Kamboh, M.I., Sanghera D.K., Ferrell R.E., DeKosky, S.T., 1995. APO* E4-associated Alzheimer's disease risk is modified by alpha1-antichymotrypsin polymorphism. Nature Genetics 10, 486-488) in 153 patients with depressive disorders and 107 healthy controls. The patients were subdivided into those with early-onset and late-onset, using 50 years as the cut-off age. There was no statistically significant difference in the age of onset of depressive disorders according to the ACT genotype. There was also no significant association between early-/late-onset depressive disorders and the ACT genotype. In addition, there was no association between the apolipoprotein E epsilon 4 allele and the ACT genotype in LOD. Our results suggest that there is no association between the ACT*A allele and LOD.