Gene Variation Tied to Rate of Age-Related Mental Decline
Decline tied to valine-to-methionine substitution at position 66 in brain-derived neurotrophic factor
THURSDAY, Oct. 27 (HealthDay News) -- A valine-to-methionine substitution at position 66 (val66met) of brain-derived neurotrophic factor (BDNF) is associated with the rate of decline in skilled task performance and age-dependent hippocampal volume changes in middle-aged and older healthy individuals, according to a study published online Oct. 25 in Translational Psychiatry.
Martha Millan Sanchez, M.D., from the Veterans Affairs Palo Alto Health Care System in California, and colleagues investigated whether val66met of pro-BDNF had a longitudinal correlation with alterations in the rate of decline in skilled task performance and structural changes in hippocampal volume. The standardized flight simulator score (SFSS, a reliable and quantifiable indicator of skilled task performance) was measured in 44 healthy Caucasian pilots (aged 40 to 69 years) who completed a minimum of three consecutive annual visits. Hippocampal volume alterations were assessed by magnetic resonance imaging in a subset of these participants.
The investigators found that val66met substitution in BDNF was associated with a longitudinal SFSS decline rate. This substitution significantly altered the structural, age-dependent hippocampal volume changes.
"We found that the val66met substitution was able to predict the rate of regression in SFSS and may be considered as a tool to evaluate the longitudinal decline in cognitive functioning of healthy individuals. Furthermore, it seems to modify the nature of the relationship between age and hippocampal volume," the authors write.