No association of angiotensin I converting enzyme I/D polymorphism with domain-specific cognitive function in aged men without dementia.

Previous research studies have related the insertion/deletion (I/D) polymorphism of the angiotensin I converting enzyme (ACE) gene to cognitive function in various neuropsychiatric or neurodegenerative disorders, but not yet investigated its genetic association with specific cognitive domains. Thus, the aim of this study was to assess the possible association of the ACE I/D polymorphism with domain-specific cognitive function in normal cognitive aging. Four hundred and sixty-nine-aged ethnic Chinese men without dementia were enrolled for genotyping and evaluated using several neuropsychological tests [Mini-Mental Status Examination (MMSE), Digit Span Forward and Backward, and Cognitive Ability Screening Instrument Chinese language version (CASI C-2.0)]. No direct association was found between ACE genotypes and the MMSE, Digit Span tests, or CASI total scores. Although subjects with I/I genotype had the lowest cognitive performance in the CASI visual construction domain (P = 0.031), this statistical difference disappeared after correction for multiple comparisons. This study suggests that the ACE I/D polymorphism does not have any genetic association with global or specific cognitive domain in aged men without dementia.