title: Decreased gray matter volume in the left middle temporal gyrus as a candidate biomarker for schizophrenia: a study of drug naive, first-episode schizophrenia patients and unaffected siblings.
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.
authors.affiliation: 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.
authors.forename: Wenbin
authors.initials: W
authors.lastname: Guo
authors.affiliation: 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.
authors.forename: Maorong
authors.initials: M
authors.lastname: Hu
authors.affiliation: University of Massachusetts Medical School, UMass Memorial Medical Center, One Biotech, Suite 100, 365 Plantation Street, Worcester, MA 01605, United States.
authors.forename: Xiaoduo
authors.initials: X
authors.lastname: Fan
authors.affiliation: 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.
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.affiliation: 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.
authors.forename: Renrong
authors.initials: R
authors.lastname: Wu
authors.affiliation: 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.
authors.forename: Jindong
authors.initials: J
authors.lastname: Chen
authors.affiliation: 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.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Guo
authors.affiliation: Mental Health Center, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, China.
authors.forename: Changqing
authors.initials: C
authors.lastname: Xiao
authors.affiliation: University of Massachusetts Medical School, UMass Memorial Medical Center, One Biotech, Suite 100, 365 Plantation Street, Worcester, MA 01605, United States.
authors.forename: Meina
authors.initials: M
authors.lastname: Quan
authors.affiliation: 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.
authors.forename: Huafu
authors.initials: H
authors.lastname: Chen
authors.affiliation: School of Mental Health, Jining Medical University, Jining, Shandong 272067, China.
authors.forename: Jinguo
authors.initials: J
authors.lastname: Zhai
authors.affiliation: 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.
authors.forename: Jingping
authors.initials: J
authors.lastname: Zhao
mesh_terms: D058068:Endophenotypes; D005260:Female; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009929:Organ Size; D011569:Psychiatric Status Rating Scales; D012372:ROC Curve; D012559:Schizophrenia / Q000175:diagnosis / Q000473:pathology*; D035781:Siblings; D013702:Temporal Lobe / Q000473:pathology*; D055815:Young Adult
keywords: Endophenotype; First-episode schizophrenia; Gray matter; Unaffected siblings; Voxel-based morphometry