val158met is not associated with Aβ-amyloid and ε4 related cognitive decline in cognitively normal older adults.

The non-synonymous single nucleotide polymorphism (SNP), Val158Met within the Catechol--methyltransferase () gene has been associated with altered levels of cognition and memory performance in cognitively normal adults. This study aimed to investigate the independent and interactional effects of Val158Met on cognitive performance. In particular, it was hypothesised that Val158Met would modify the effect of neocortical Aβ-amyloid (Aβ) accumulation and carriage of the apolipoprotein E ( ε4 allele on cognition in preclinical Alzheimer's disease (AD). In 598 cognitively normal older adults with known neocortical Aβ levels, linear mixed modelling revealed no significant independent or interactional associations between Val158Met and cognitive decline. These findings do not support previous associations between Val158Met and cognitive performance and suggest this variant does not influence Aβ-amyloid or ε4 driven cognitive decline in a well characterised cohort of cognitively normal older adults.