title: Elevated mitochondrial DNA copy number in peripheral blood cells is associated with childhood autism.
abstract: BACKGROUND
  Several lines of evidence indicate mitochondrial impairment in the pathophysiology of autism. As one of the most common biomarkers for mitochondrial dysfunction, mitochondrial DNA (mtDNA) copy number has also been linked to autism, but the relationship between mtDNA copy number and autism was still obscured. In this study, we performed a case-control study to investigate whether mtDNA copy number in peripheral blood cells is related to patients with autism.
  
  
  METHODS
  Relative mtDNA copy number in peripheral blood cells was measured by using real-time polymerase chain reaction method. The participants in this study included 78 patients with childhood autism and 83 typically developing children.
  
  
  RESULTS
  We observed children with autism had significantly elevated relative mtDNA copy number than healthy controls (Beta = -0.173, P = 0.0003). However, there were no significant correlations between mtDNA copy number and clinical features (paternal age, maternal age, age of onset, illness of duration, CARS score and ABC score) in childhood autism.
  
  
  CONCLUSIONS
  We show that elevated mtDNA copy number in peripheral blood is associated with autism, indicating that there may be mitochondrial dysfunction in children with autism.
authors.affiliation: The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, 325027, China. chenshan0121@163.com.
authors.forename: Shan
authors.initials: S
authors.lastname: Chen
authors.affiliation: Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China. zongchanglicn@gmail.com.
authors.forename: Zongchang
authors.initials: Z
authors.lastname: Li
authors.affiliation: Institute of Mental Health of the Second Xiangya Hospital, National Laboratory for Psychiatric Disease Diagnosis and Treatment, Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Central South University, Changsha, China. heying@dr.com.
authors.forename: Ying
authors.initials: Y
authors.lastname: He
authors.affiliation: Institute of Mental Health of the Second Xiangya Hospital, National Laboratory for Psychiatric Disease Diagnosis and Treatment, Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Central South University, Changsha, China. fzhang20@jhmi.edu.|The National Clinical Research Center for Psychiatric and Psychological Diseases, Changsha, China. fzhang20@jhmi.edu.|Division of Clinical Sciences, Lieber Institute for Brain Development, John Hopkins University Medical Campus, 855 N. Wolfe Street, Suite 300, Baltimore, 21205, MD, USA. fzhang20@jhmi.edu.
authors.forename: Fengyu
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Institute of Mental Health of the Second Xiangya Hospital, National Laboratory for Psychiatric Disease Diagnosis and Treatment, Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Central South University, Changsha, China. lh3067@163.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.affiliation: Institute of Mental Health of the Second Xiangya Hospital, National Laboratory for Psychiatric Disease Diagnosis and Treatment, Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Central South University, Changsha, China. tangliaoyanhui@gmail.com.
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Liao
authors.affiliation: Department of Women's Health Care, The Affiliated Shenzhen Maternal and Child Health Care Hospital, Nanfang University of Medical Science, Shenzhen, China. weizhen14@163.com.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wei
authors.affiliation: Department of Women's Health Care, The Affiliated Shenzhen Maternal and Child Health Care Hospital, Nanfang University of Medical Science, Shenzhen, China. wgb1978@yahoo.com.cn.
authors.forename: Guobin
authors.initials: G
authors.lastname: Wan
authors.affiliation: BGI Ark Biotechnology Co., Ltd., Shenzhen, Guangdong, China. xiangxihaha@163.com.
authors.forename: Xi
authors.initials: X
authors.lastname: Xiang
authors.affiliation: Institute of Mental Health of the Second Xiangya Hospital, National Laboratory for Psychiatric Disease Diagnosis and Treatment, Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Central South University, Changsha, China. humaolin@126.com.
authors.forename: Maolin
authors.initials: M
authors.lastname: Hu
authors.affiliation: The State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China. xiakun48@163.com.
authors.forename: Kun
authors.initials: K
authors.lastname: Xia
authors.affiliation: The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, 325027, China. chenxghn@gmail.com.|Institute of Mental Health of the Second Xiangya Hospital, National Laboratory for Psychiatric Disease Diagnosis and Treatment, Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Central South University, Changsha, China. chenxghn@gmail.com.|The National Clinical Research Center for Psychiatric and Psychological Diseases, Changsha, China. chenxghn@gmail.com.
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Chen
authors.affiliation: Institute of Mental Health of the Second Xiangya Hospital, National Laboratory for Psychiatric Disease Diagnosis and Treatment, Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Central South University, Changsha, China. tangjinsonghn@gmail.com.|The National Clinical Research Center for Psychiatric and Psychological Diseases, Changsha, China. tangjinsonghn@gmail.com.|Division of Clinical Sciences, Lieber Institute for Brain Development, John Hopkins University Medical Campus, 855 N. Wolfe Street, Suite 300, Baltimore, 21205, MD, USA. tangjinsonghn@gmail.com.
authors.forename: Jinsong
authors.initials: J
authors.lastname: Tang
mesh_terms: D001321:Autistic Disorder / Q000209:etiology* / Q000378:metabolism*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D056915:DNA Copy Number Variations / Q000502:physiology*; D004272:DNA, Mitochondrial / Q000378:metabolism*; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D028361:Mitochondrial Diseases / Q000150:complications* / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D004272:DNA, Mitochondrial