Nanfang Pan1, Yajing Long1, Ying Chen1, and Qiyong Gong1
1West China Hospital of Sichuan University, Chengdu, China
Synopsis
Keywords: White Matter, Brain Connectivity, Transcriptome
Motivation: The research aims to uncover intricate gray-white matter structural connectivity (GWSC) patterns and associated gene expression profiles in ADHD.
Goal(s): Develop machine-learning classifiers based on GWSC to distinguish ADHD from controls, bridging its gap with gene expression to unveil neurobiological mechanisms.
Approach: Utilize T1-weighted and diffusion-weighted MRI data to construct GWSC networks. Employed four machine-learning classifiers for classification. Analyzed transcriptomes from the Allen Human Brain Atlas to link with gene expression.
Results: Classifiers achieved over 75% accuracy, with Gaussian-kernel SVM leading at 82.6%. Ventromedial prefrontal cortex emerged as a key contributor. Transcriptome analysis identified enrichment in "neuron projection development."
Impact: These findings empower clinicians with
accurate ADHD classifiers and pinpoint the ventromedial prefrontal
cortex as a hub. The revelation of gene expression nuances in neuron
projection development advances targeted interventions, fostering a shift
towards more personalized and effective ADHD treatments.
Introduction
Attention-Deficit/Hyperactivity Disorder
(ADHD) stands as a complex neurodevelopmental disorder, drawing considerable
focus in the realm of neuroimaging psychiatry. While aberrations in the neural
mechanisms of both brain gray matter and white matter have been extensively
pinpointed, the intricate patterns of their structural connectivity coupling
and the concurrent gene expression profiles continue to elude comprehensive
understanding. Herein, we established machine-learning classifiers based on
Gray-White Matter Structural Connectivity Coupling (GWSC) patterns, with a
parallel exploration to unravel the underlying transcriptomes.Material and Methods
T1-weighted and diffusion-weighted MRI data
were obtained from a cohort of children with ADHD (n = 83) and typically
developing children (n = 89). Gray matter covariance networks and white matter
connectivity networks were constructed using the Kullback-Leibler divergence
similarity measure and probabilistic tractography respectively. We computed the
strength of their regional coupling as we termed GWSC coupling. To individually
classify ADHD children from typically developing controls, we established the
machine-learning pipeline in pursuit of clinical applicability. Four configure
learning algorithms, namely linear support vector machine (SVM),
Gaussian-kernel SVM, k-nearest neighbors, and decision tree were employed to
build up fitting models. Finally, we extracted gene expression data from the
Allen Human Brain Atlas and performed partial least squares regression analysis
to bridge the gap between abnormal GWSC coupling patterns and microarray-based
transcriptomes, and gene enrichment analysis was conducted to interpret the
inference of enriched gene ontology biological processes.Results
All four classifiers we employed
distinguished children with ADHD with more than 75% accuracy, wherein the
Gaussian-kernel SVM enables the highest accuracy of 82.6% (95%CI: 78.4%-86.8%).
Sensitivity and specificity for the discrimination were 79.5% and 85.4% respectively.
In this model, the GWSC couplings in the ventromedial prefrontal cortex
provided the greatest contribution to the classifier. After correcting for
enrichment terms (pFDR<.05) and discarding discrete
enrichment clusters, the top significant gene ontology biological process is “neuron
projection development”.Conclusions
By constructing GWSC coupling patterns in
ADHD, we developed machine-learning classifiers with acceptable predictive
performance, with the ventromedial prefrontal cortex severed as a central substrate. Our transcriptional findings reveal
the involvement of neuron projection in the psychopathological processes of
GWSC patterns in ADHD. We uncovered GWSC coupling phenotypes in ADHD and
identified their transcriptional signatures, facilitating a more comprehensive
understanding of ADHD.Acknowledgements
This
work was supported by the National Natural Science Foundation of China
(QG, grants 81621003 and 82027808).References
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