The brain-derived neurotrophic factor Val66Met genotype does not influence the grey or white matter structures underlying recognition memory

Abstract

A single nucleotide polymorphism (SNP) in the gene coding for brain-derived neurotrophic factor (BDNF) has previously been associated with a reduction in recognition memory performance. While previous findings have highlighted that this SNP contributes to recognition memory, little is known about its influence on subprocesses of recognition, familiarity and recollection. Previous research has reported reduced hippocampal volume and decreased fractional anisotropy in carriers of the Met allele across a range of white matter tracts, including those networks that may support recognition memory. Here, in a sample of 61 healthy young adults, we used a source memory task to measure accuracy on each recognition subprocess, in order to determine whether the Val66Met SNP (rs6265) influences these equally. Additionally, we compared grey matter volume between these groups for structures that underpin familiarity and recollection separately. Finally, we used probabilistic tractography to reconstruct tracts that subserve each of these two recognition systems.Behaviourally, we found group differences on the familiarity measure, but not on recollection. However, we did not find any group difference on grey-or white-matter structures. Together, these results suggest a functional influence of the Val66Met SNP that is independent of coarse structural changes, and nuance previous research highlighting the relationship between BDNF, brain structure, and behaviour.

Investigating the Influence of the Brain-Derived Neurotrophic Factor Val66Met Single Nucleotide Polymorphism on Familiarity and Recollection Event-Related Potentials

“…Given that other research groups have argued 38 VAL66MET GENOTYPE INFLUENCES RECOGNITION ERPs familiarity to also modulate the LPC, we propose our findings might best be described as reflecting the impact of the Val66Met SNP on general recognition, or potentially on familiarity-related recognition. Importantly, these behavioural and electrophysiological results are reported in the absence of any major structural changes within the brain (see McKay et al, 2019). We, therefore, propose that these results are evidence of a functional influence of the Val66Met SNP on recognition memory.…”

“…Genotyped participants were divided into two groups, those with the Val/Val genotype, and those with at least one copy of the Met allele. A subset of sixty-one of the participants that completed the EEG task also participated in an MRI, which has been previously reported (McKay, Moreau, Henare, & Kirk, 2019) . All participants gave informed consent, and this study was approved by the University of Auckland Human Participants Ethics Committee.…”

“…While the current study does not directly investigate this question, a subset of these individuals also participated in an MRI study that aimed to investigate possible structural differences associated with the Val66Met SNP (McKay et al, 2019) . This study found no detectable differences in ROI or global analyses for either grey-or white-matter measures, and therefore, instils some confidence that our results might not be an artefact of large structural variations in these groups.…”

Vitamin D, Folate, and Cobalamin Serum Concentrations Are Related to Brain Volume and White Matter Integrity in Urban Adults

“…A third analysis included the smaller regions, accounting for bilateral volumes, yielding 142 outcome measures (Model C). Finally, dMRI measures were included, after taking the average between the left and right side for FA and MD measures, as done previously (McKay et al, 2019). This exploratory approach was conducted previously by at least one other study of vitamin D deficiency and WMI (Moon et al, 2015).…”

Do Brain-Derived Neurotrophic Factor Genetic Polymorphisms Modulate the Efficacy of Motor Cortex Plasticity Induced by Non-invasive Brain Stimulation? A Systematic Review

“…When the interaction of cortical volume with the NIBS effect was considered, the volume of the sensorimotor cortex positively predicted the NIBS effect on MEP changes (Conde et al, 2012). However, this hypothesis lacks reliable information, because the different cortical volumes did not correspond to the same regions (Yang et al, 2012;Jasińska et al, 2017;Shen et al, 2020), and some studies failed to show the genotype-related cortical volume changes (Kim et al, 2015;McKay et al, 2019). Moreover, one study showed that the M1 volume in the Met/Met group was larger than that in the other groups (Jasińska et al, 2017).…”