Gray matter heritability in family-based and population-based studies using voxel-based morphometry.

Area of Science:

• Neuroimaging
• Genetics
• Brain Anatomy

Background:

• High-resolution structural imaging and genetics advance brain understanding through aggregate measures.
• Voxel-wise analyses offer detailed insights into genetic influences on brain structure.

Purpose of the Study:

• To conduct a large-scale study on gray matter heritability at high voxel resolution (1x1x1 mm).
• To explore the potential of voxel-wise heritability mapping for understanding genetic contributions to brain structure.

Main Methods:

• Applied validated voxel-based morphometry (VBM) protocols to MRI data from 3,239 unrelated and 491 family-based subjects.
• Utilized genome-wide genetic data and pedigree structures to estimate voxel-wise gray matter heritability.
• Associated genetic variants linked to subcortical volume with highly heritable voxels to enhance association signals.

Main Results:

• Significantly heritable voxels were identified in subcortical structures and left hemisphere language areas.
• Family-based heritability estimates were higher than population-based estimates, yet regional consistency was high (r=0.73).
• Association signals for genetic loci related to subcortical volume were enhanced by focusing on the most heritable voxels.

Conclusions:

• Gray matter voxel-wise heritability is reliably estimable using various methods.
• Combining heritability estimates across studies enables the construction of robust gray matter heritability maps.