Altered white matter architecture in BDNF met carriers

Area of Science:

• Neuroscience
• Genetics
• Neuroimaging

Background:

• Brain-derived neurotrophic factor (BDNF) regulates synaptic pruning and axonal maintenance.
• The Met allele of the BDNF gene is associated with reduced activity-dependent neurotrophin release.

Purpose of the Study:

• To investigate the impact of BDNF genotype on structural brain network connectivity.
• To determine if structural brain networks differ between individuals with the BDNF Met allele and Val/Val genotype.

Main Methods:

• Diffusion-weighted imaging (DWI) was used to construct structural brain networks in 36 healthy subjects.
• Permutation testing identified differences in connection strength based on BDNF genotype.
• A Gaussian process classifier achieved 86% accuracy in identifying allelic groups.

Main Results:

• Met allele carriers exhibited significantly increased structural connectivity throughout the forebrain.
• Elevated connectivity was observed in the corona radiata, corticothalamic/corticospinal pathways, and corpus callosum.
• Increased interhemispheric connectivity was noted via the corpus callosum and anterior commissure.

Conclusions:

• Decreased BDNF availability in Met allele carriers may lead to axonal maintenance deficits.
• These deficits result in mesoscale alterations in white matter architecture.
• Structural brain network differences are detectable and predictable based on BDNF genotype.