HealthDay News — There are significant differences in the development of 12 fiber tracts between infants with fragile X syndrome (FXS) and controls, according to a study published online April 4 in JAMA Psychiatry.
Meghan R. Swanson, Ph.D., from the University of North Carolina at Chapel Hill, and colleagues characterized development of white matter at age 6, 12, and 24 months in infants with FXS and typically developing controls. Longitudinal behavioral and brain imaging data were obtained from 27 infants with FXS and 73 typically developing controls with no first- or second-degree relatives with intellectual or psychiatric disorders.
The researchers identified significant differences in the development of 12 of 19 fiber tracts between the infants with FXS and controls, with lower fractional anisotropy in bilateral subcortical-frontal, occipital-temporal, temporal-frontal, and cerebellar-thalamic pathways and in four of six corpus callosum subdivisions. Significant main effects were seen between groups for all 12 of these pathways but not for the interaction of age × group; this indicated that in the FXS group, lower fractional anisotropy was stable from age 6 months.
In the FXS group, there was a correlation for lower fractional anisotropy values in the uncinate fasciculi with lower nonverbal development quotient.
“The results substantiate in human infants the essential role of fragile X gene expression in the early development of white matter,” the authors write.