title: Differential methylation of the oxytocin receptor gene in patients with anorexia nervosa: a pilot study.
abstract: OBJECTIVE
  Recent studies in patients with anorexia nervosa suggest that oxytocin may be involved in the pathophysiology of anorexia nervosa. We examined whether there was evidence of variation in methylation status of the oxytocin receptor (OXTR) gene in patients with anorexia nervosa that might account for these findings.
  
  
  METHODS
  We analyzed the methylation status of the CpG sites in a region from the exon 1 to the MT2 regions of the OXTR gene in buccal cells from 15 patients and 36 healthy women using bisulfite sequencing. We further examined whether methylation status was associated with markers of illness severity or form.
  
  
  RESULTS
  We identified six CpG sites with significant differences in average methylation levels between the patient and control groups. Among the six differentially methylated CpG sites, five showed higher than average methylation levels in patients than those in the control group (64.9-88.8% vs. 6.6-45.0%). The methylation levels of these five CpG sites were negatively associated with body mass index (BMI). BMI, eating disorders psychopathology, and anxiety were identified in a regression analysis as factors affecting the methylation levels of these CpG sites with more variation accounted for by BMI.
  
  
  CONCLUSIONS
  Epigenetic misregulation of the OXTR gene may be implicated in anorexia nervosa, which may either be a mechanism linking environmental adversity to risk or may be a secondary consequence of the illness.
authors: Department of Psychiatry, Inje University, Seoul Paik Hospital, Seoul, Republic of Korea.
authors: Youl-Ri
authors: YR
authors: Kim
authors: Indang Institute of Molecular Biology, Inje University, Seoul, Republic of Korea ; School of Biological Sciences, Inje University, Gimhae, Republic of Korea.
authors: Jeong-Hyun
authors: JH
authors: Kim
authors: Indang Institute of Molecular Biology, Inje University, Seoul, Republic of Korea.
authors: Mi Jeong
authors: MJ
authors: Kim
authors: Section of Eating Disorders, Department of Psychological Medicine, King's College London, Institute of Psychiatry, London, United Kingdom.
authors: Janet
authors: J
authors: Treasure
mesh_terms: D000328:Adult; D000856:Anorexia Nervosa / Q000235:genetics*; D015992:Body Mass Index; D016022:Case-Control Studies; D018899:CpG Islands; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005260:Female; D006801:Humans; D010865:Pilot Projects; D018045:Receptors, Oxytocin / Q000235:genetics* / Q000378:metabolism; D012306:Risk; D017422:Sequence Analysis, DNA; D013447:Sulfites / Q000737:chemistry; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: C569600:OXTR protein, human; D018045:Receptors, Oxytocin; D013447:Sulfites; C042345:hydrogen sulfite