title: Number of X-chromosome genes influences social behavior and vasopressin gene expression in mice.
abstract: Sex differences in behavior are widespread and often caused by hormonal differences between the sexes. In addition to hormones, the composition and numbers of the sex chromosomes also affect a variety of sex differences. In humans, X-chromosome genes are implicated in neurobehavioral disorders (i.e. fragile-X, autism). To investigate the role of X-chromosome genes in social behavior, we used a mouse model that has atypical sex chromosome configurations resembling Turner (45, XO) and Klinefelter syndromes (47, XXY). We examined a number of behaviors in juvenile mice. Mice with only one copy of most X-chromosome genes, regardless of gonadal sex, were less social in dyadic interaction and social preference tasks. In the elevated plus maze, mice with one X-chromosome spent less time in the distal ends of the open arms as compared to mice with two copies of X-chromosome genes. Using qRTPCR, we noted that amygdala from female mice with one X-chromosome had higher expression levels of vasopressin (Avp) as compared to mice in the other groups. Finally, in plasma from girls with Turner syndrome we detected reduced vasopressin (AVP) concentrations as compared to control patients. These novel findings link sex chromosome genes with social behavior via concentrations of AVP in brain, adding to our understanding of sex differences in neurobehavioral disorders.
authors.affiliation: Department of Biochemistry and Molecular Genetics and Neuroscience Graduate Program, University of Virginia School of Medicine, Charlottesville, VA 22908, United States.
authors.forename: Kimberly H
authors.initials: KH
authors.lastname: Cox
authors.affiliation: Department of Biochemistry and Molecular Genetics and Neuroscience Graduate Program, University of Virginia School of Medicine, Charlottesville, VA 22908, United States.
authors.forename: Kayla M
authors.initials: KM
authors.lastname: Quinnies
authors.affiliation: Department of Biochemistry and Molecular Genetics and Neuroscience Graduate Program, University of Virginia School of Medicine, Charlottesville, VA 22908, United States.
authors.forename: Alex
authors.initials: A
authors.lastname: Eschendroeder
authors.affiliation: Section of Pediatric Endocrinology, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46292, United States.
authors.forename: Paula M
authors.initials: PM
authors.lastname: Didrick
authors.affiliation: Section of Pediatric Endocrinology, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46292, United States.
authors.forename: Erica A
authors.initials: EA
authors.lastname: Eugster
authors.affiliation: Department of Biochemistry and Molecular Genetics and Neuroscience Graduate Program, University of Virginia School of Medicine, Charlottesville, VA 22908, United States. Electronic address: efrissma@ncsu.edu.
authors.forename: Emilie F
authors.initials: EF
authors.lastname: Rissman
mesh_terms: D000679:Amygdala / Q000378:metabolism; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002648:Child; D005260:Female; D018628:Gene Dosage; D005786:Gene Expression Regulation / Q000235:genetics*; D050172:Genes, X-Linked; D006801:Humans; D008297:Male; D051379:Mice; D012919:Social Behavior; D014424:Turner Syndrome / Q000097:blood / Q000235:genetics; D014667:Vasopressins / Q000235:genetics* / Q000378:metabolism; D014960:X Chromosome / Q000235:genetics*
chemical_list: D014667:Vasopressins
keywords: Anxiety; Klinefelter syndrome; Sex differences; Sexual differentiation; Social anxiety; Social behavior; Turner syndrome