title: X Chromosome Inactivation in Opioid Addicted Women.
abstract: BACKGROUND
  X chromosome inactivation (XCI) is a process during which one of the two X chromosomes in female human is silenced leading to equal gene expression with males who have only one X chromosome. Here we have investigated XCI ratio in females with opioid addiction to see whether XCI skewness in women could be a risk factor for opioid addiction.
  
  
  METHODS
  30 adult females meeting DSM IV criteria for opioid addiction and 30 control females with no known history of addiction were included in the study. Digested and undigested DNA samples which were extracted from blood were analyzed after amplification of the polymorphic androgen receptor (AR) gene located on the X chromosome. XCI skewness was studied in 3 ranges: 50:50-64:36 (random inactivation), 65:35-80:20 (moderately skewed) and >80:20 (highly skewed).
  
  
  RESULTS
  XCI from informative females in control group was 63% (N=19) random, 27% (N=8) moderately skewed and 10% (N=3) highly skewed. Addicted women showed 57%, 23% and 20%, respectively. The distribution and frequency of XCI status in women with opioid addiction was not significantly different from control group (P=0.55).
  
  
  CONCLUSIONS
  Our data did not approve our hypothesis of increased XCI skewness among women with opioid addiction or unbalanced (non-random) expression of genes associated with X chromosome in female opioid addicted subjects.
authors.affiliation: Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.; Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Nasim
authors.initials: N
authors.lastname: Vousooghi
authors.affiliation: Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.; Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mitra-Sadat Sadat
authors.initials: MS
authors.lastname: Shirazi
authors.affiliation: Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Goodarzi
authors.affiliation: Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Peyman Hassani
authors.initials: PH
authors.lastname: Abharian
authors.affiliation: Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran.; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.; Department of Cognitive Neuroscience, Institute for Cognitive Science Studies, Tehran, Iran.; Genomics Center, School of Advanced Sciences, Tehran Medical Branch, Islamic Azad University, Tehran, Iran.; School of Cognitive Sciences, Institute for Studies in Theoretical Physics and Mathematics, Tehran, Iran.
authors.forename: Mohammad-Reza
authors.initials: MR
authors.lastname: Zarrindast
keywords: Opiate addiction; Women; X Chromosome inactivation