White matter microstructure in 22qll deletion syndrome: a pilot diffusion tensor imaging and voxel-based morphometry study of children and adolescents

摘要

Abstract Young people with 22qll Deletion Syndrome (22qllDS) are at substantial risk for developing psychosis and have significant differences in white matter (WM) volume. However, there are few in vivo studies of both WM microstructural integrity (as measured using Diffusion Tensor (DT)-MRI) and WM volume in the same individual. We used DT-MRI and structural MRI (sMRI) with voxelbased morphometry (VBM) to compare, respectively, the fractional anisotropy (FA) and WM volume of 11 children and adolescents with 22qllDS and 12 controls. Also, within 22qllDS we related differences in WM to severity of schizotypy, and polymorphism of the catechol-O-methyltransferase (COMT) gene. People with 22qllDS had significantly lower FA in inter-hemispheric and brainstem and frontal, parietal and temporal lobe regions after co vary ing for IQ. Significant WM volumetric increases were found in the internal capsule, anterior brainstem and frontal and occipital lobes. There was a significant negative correlation between increased schizotypy scores and reduced WM FA in the right posterior limb of internal capsule and the right body and left splenium of corpus callosum. Finally, the Val allele of COMT was associated with a significant reduction in both FA and volume of WM in the frontal lobes, cingulum and corpus callosum. Young people with 22qllDS have significant differences in both WM microstructure and volume. Also, there is preliminary evidence that within 22qllDS, some regional differences in FA are associated with allelic variation in COMT and may perhaps also be associated with schizotypy.