White matter microstructure mediates the pairwise relationship between childhood maltreatment, microRNA-9, and the severity of major depressive disorder

To describe the gene–behavioral–brain relationship, diffusion tensor imaging (DTI) was used to quantitatively assess WM, offering information about axonal size, myelination, and orientation. A previous study indicated that CM affects miR-9 levels, potentially affecting MDD. miR-9 alterations in stress models affect MDD symptoms. [...]this study proposes a two-step mediation model, testing the effects of interest. Tract-based spatial statistics (TBSS) was employed for voxelwise statistical analysis of DTI data, involving registration, skeletonization, and projection onto the WM skeleton to analyze fractional anisotropy (FA). [...]through multiple linear regression analysis, the main effect of CM on brain networks was determined [Supplementary Figure 2A, http://links.lww.com/CM9/C61].