Wenbin Guo1, Maorong Hu2, Xiaoduo Fan3, Feng Liu4, Renrong Wu5, Jindong Chen5, Xiaofeng Guo5, Changqing Xiao6, Meina Quan3, Huafu Chen4, Jinguo Zhai7, Jingping Zhao8. 1. Mental Health Institute of the Second Xiangya Hospital, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China; Mental Health Center, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, China. 2. Mental Health Institute of the Second Xiangya Hospital, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China; Mental Hospital of Nanchang University & Mental Health Center of Jiangxi Province, Nanchang, 330029, China. 3. University of Massachusetts Medical School, UMass Memorial Medical Center, One Biotech, Suite 100, 365 Plantation Street, Worcester, MA 01605, United States. 4. Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China. 5. Mental Health Institute of the Second Xiangya Hospital, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China. 6. Mental Health Center, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, China. 7. School of Mental Health, Jining Medical University, Jining, Shandong 272067, China. 8. Mental Health Institute of the Second Xiangya Hospital, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China; The Second Affiliated Hospital of Xinxiang Medical University, Henan Province Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, Henan 453002, China. Electronic address: edsgwb@126.com.
Abstract
BACKGROUND: Studies have shown that patients with schizophrenia and their siblings share decreased gray matter (GM) volumes in certain brain regions, which may represent candidate endophenotypes of schizophrenia. However, the specificity and utility of these possible endophenotypes in relation to schizophrenia remain unclear. METHODS: Twenty drug-naive, first-episode schizophrenia patients and 20 first-degree unaffected siblings from the same families as the patients (USS group), a separate group of 25 first-degree unaffected siblings of schizophrenia patients from other families (USO group), and 43 healthy controls were recruited. Voxel-based morphometry (VBM) was used to analyze structural imaging data. RESULTS: The VBM analysis showed a significant difference in GM volume between the combined sibling group and the control group in the left middle temporal gyrus (MTG). Group comparison showed that the patients, the USS, and the USO had significantly decreased GM volume of the left MTG compared with the controls; such a difference did not exist among the patients and the two sibling groups. A receiver operating characteristic curve (ROC curve) analysis showed good predictive value of the mean cluster volume in the left MTG to distinguish patients, USS, and USO from healthy controls. There were no significant correlations between the mean cluster volume in the left MTG and clinical variables in the patients. CONCLUSIONS: The GM volume decrease of the left MTG may be utilized as a candidate biomarker for schizophrenia. The novel design of including a USO group in our study enhances both the specificity and the heritability of the biomarker identified.
BACKGROUND: Studies have shown that patients with schizophrenia and their siblings share decreased gray matter (GM) volumes in certain brain regions, which may represent candidate endophenotypes of schizophrenia. However, the specificity and utility of these possible endophenotypes in relation to schizophrenia remain unclear. METHODS: Twenty drug-naive, first-episode schizophreniapatients and 20 first-degree unaffected siblings from the same families as the patients (USS group), a separate group of 25 first-degree unaffected siblings of schizophreniapatients from other families (USO group), and 43 healthy controls were recruited. Voxel-based morphometry (VBM) was used to analyze structural imaging data. RESULTS: The VBM analysis showed a significant difference in GM volume between the combined sibling group and the control group in the left middle temporal gyrus (MTG). Group comparison showed that the patients, the USS, and the USO had significantly decreased GM volume of the left MTG compared with the controls; such a difference did not exist among the patients and the two sibling groups. A receiver operating characteristic curve (ROC curve) analysis showed good predictive value of the mean cluster volume in the left MTG to distinguish patients, USS, and USO from healthy controls. There were no significant correlations between the mean cluster volume in the left MTG and clinical variables in the patients. CONCLUSIONS: The GM volume decrease of the left MTG may be utilized as a candidate biomarker for schizophrenia. The novel design of including a USO group in our study enhances both the specificity and the heritability of the biomarker identified.