title: DNA methylation profiles of elderly individuals subjected to indentured childhood labor and trauma.
abstract: Childhood trauma is associated with increased vulnerability to mental and somatic disorders later in life. Epigenetic modifications such as DNA methylation are one potential mechanism through which such long-lasting impairments/consequences can be explained. The aim of the present study was to investigate whether childhood trauma is associated with long-term DNA methylation alterations in old age.
  
  
  
  We assessed genome-wide DNA methylation profiles in a cohort of former indentured child laborers ("Verdingkinder") who suffered severe childhood adversities (N = 30; M age = 75.9 years), and compared them to control group with similar demographic characteristics (N = 15, M age = 72.8 years). DNA was isolated from epithelial buccal cells and hybridized to the Illumina Infinium 450 k DNA methylation array, which provides coverage of 485,000 methylation sites.
  
  
  
  After accounting for batch effects, age, gender and multiple testing, 71 differentially methylated CpG positions were identified between the two groups. They were annotated among others to genes involved in neuronal projections and neuronal development. Some of the identified genes with differential methylation (DLG associated protein 2, mechanistic target of rapamycin) have previously been associated with traumatic stress.
  
  
  
  The results indicate specific epigenetic alterations in elderly individuals who were subjected to childhood adversities. Psychiatric and somatic comorbidities as well as differences in buccal epithelial cells proportion may contribute to the observed epigenetic differences.
authors.affiliation: Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, Neumunsterallee 9, 8032, Zurich, Switzerland. zoyamarinova@gmail.com.
authors.forename: Zoya
authors.initials: Z
authors.lastname: Marinova
authors.affiliation: Department of Psychology, University of Zurich, Zurich, Switzerland.|University Research Priority Program Dynamics of Healthy Aging, University of Zurich, Zurich, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Maercker
authors.affiliation: Department of Psychology, University of Zurich, Zurich, Switzerland.|University Research Priority Program Dynamics of Healthy Aging, University of Zurich, Zurich, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Küffer
authors.affiliation: Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland.|SIB Swiss Institute of Bioinformatics, University of Zurich, Zurich, Switzerland.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Robinson
authors.affiliation: Aarhus Institute of Advanced Studies, University of Aarhus, Aarhus, Denmark.
authors.forename: Tomasz K
authors.initials: TK
authors.lastname: Wojdacz
authors.affiliation: Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, Neumunsterallee 9, 8032, Zurich, Switzerland.|Neuroscience Center Zurich, University of Zurich and the ETH Zurich, Zurich, Switzerland.|Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
authors.forename: Susanne
authors.initials: S
authors.lastname: Walitza
authors.affiliation: Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, Neumunsterallee 9, 8032, Zurich, Switzerland.|Neuroscience Center Zurich, University of Zurich and the ETH Zurich, Zurich, Switzerland.|Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
authors.forename: Edna
authors.initials: E
authors.lastname: Grünblatt
authors.affiliation: Department of Psychology, University of Zurich, Zurich, Switzerland.|Health and Rehabilitation Research Institute, Auckland University of Technology, Auckland, New Zealand.|Waitemata Pain Service, Department of Anaesthesia and Perioperative Medicine, North Shore Hospital, Auckland, New Zealand.
authors.forename: Andrea
authors.initials: A
authors.lastname: Burri
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002648:Child; D002649:Child Abuse; D018899:CpG Islands; D004247:DNA / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D019175:DNA Methylation; D005260:Female; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics; D008297:Male; D009061:Mouth Mucosa / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011506:Proteins / Q000235:genetics
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D011506:Proteins; C554821:SEC14L4 protein, human; C116431:src kinase associated phosphoprotein 2; D004247:DNA