Department of Psychiatry, Pontificia Universidad Católica de Chile, Santiago, Chile.
Department of Psychiatry, UMC Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands.
Sci Rep. 2021 Nov 3;11(1):21623. doi: 10.1038/s41598-021-00873-8.
The 22q11 deletion syndrome is a genetic disorder associated with a high risk of developing psychosis, and is therefore considered a neurodevelopmental model for studying the pathogenesis of schizophrenia. Studies have shown that localized abnormal functional brain connectivity is present in 22q11 deletion syndrome like in schizophrenia. However, it is less clear whether these abnormal cortical interactions lead to global or regional network disorganization as seen in schizophrenia. We analyzed from a graph-theory perspective fMRI data from 40 22q11 deletion syndrome patients and 67 healthy controls, and reconstructed functional networks from 105 brain regions. Between-group differences were examined by evaluating edge-wise strength and graph theoretical metrics of local (weighted degree, nodal efficiency, nodal local efficiency) and global topological properties (modularity, local and global efficiency). Connectivity strength was globally reduced in patients, driven by a large network comprising 147 reduced connections. The 22q11 deletion syndrome network presented with abnormal local topological properties, with decreased local efficiency and reductions in weighted degree particularly in hub nodes. We found evidence for abnormal integration but intact segregation of the 22q11 deletion syndrome network. Results suggest that 22q11 deletion syndrome patients present with similar aberrant local network organization as seen in schizophrenia, and this network configuration might represent a vulnerability factor to psychosis.
22q11 缺失综合征是一种与精神病发病风险较高相关的遗传疾病，因此被认为是研究精神分裂症发病机制的神经发育模型。研究表明，22q11 缺失综合征中存在局部异常的功能性脑连接，与精神分裂症相似。然而，目前尚不清楚这些异常的皮质相互作用是否会导致精神分裂症中所见的全局或局部网络紊乱。我们从图论的角度分析了 40 名 22q11 缺失综合征患者和 67 名健康对照者的 fMRI 数据，并从 105 个脑区重建了功能网络。通过评估边缘强度和局部（加权度数、节点效率、节点局部效率）和全局拓扑属性（模块性、局部和全局效率）的图论度量，来检查组间差异。患者的连接强度普遍降低，这是由包含 147 个减少连接的大型网络驱动的。22q11 缺失综合征网络呈现出异常的局部拓扑性质，局部效率降低，加权度数减少，特别是在枢纽节点。我们发现了 22q11 缺失综合征网络异常整合但完整分离的证据。结果表明，22q11 缺失综合征患者表现出与精神分裂症相似的异常局部网络组织，这种网络配置可能是精神病的易患因素。
