DCDC2 polymorphism is associated with left temporoparietal gray and white matter structures during development

Area of Science:

• Neuroscience
• Genetics
• Developmental Biology

Background:

• DYX1C1, DCDC2, and KIAA0319 genes are linked to dyslexia, neuronal migration, and ciliary function.
• Specific polymorphisms (rs3743204, rs793842, rs6935076) correlate with white matter volume in the left temporoparietal region.

Purpose of the Study:

• To investigate the relationship between these genetic polymorphisms and cortical thickness in developing children.
• To explore how genetic variations, white matter volume, and cortical thickness interact to influence reading comprehension.

Main Methods:

• Longitudinal neuroimaging study of 76 children and young adults scanned up to three times over 2 years.
• Analysis of associations between DCDC2 rs793842 polymorphism and cortical thickness in specific brain regions.
• Correlation analysis between white matter volume, cortical thickness, and reading comprehension scores.

Main Results:

• The DCDC2 rs793842 polymorphism was significantly associated with cortical thickness in the left angular, supramarginal, and lateral occipital cortex.
• T-allele carriers exhibited thicker cortices but reduced white matter volume and lower reading comprehension.
• White matter volume, not cortical thickness, predicted reading comprehension 2 years post-scan.

Conclusions:

• Normal variability in reading comprehension is linked to genetic factors (DCDC2), white matter volume, and cortical thickness in the inferior parietal lobe.
• The findings suggest DCDC2's role in ciliary function may influence both neuronal development and reading abilities.