title: Epigenetic variation in the serotonin transporter gene predicts resting state functional connectivity strength within the salience-network.
abstract: Genetic variation in the serotonin transporter gene (SLC6A4) has been associated with psychopathology and aberrant brain functioning in a plethora of clinical and imaging studies. In contrast, the neurobiological correlates of epigenetic signatures in SLC6A4, such as DNA methylation profiles, have only recently been explored in human brain imaging research. The present study is the first to apply a resting state functional magnetic resonance imaging approach to identify changes in brain networks related to SLC6A4 promoter methylation (N=74 healthy individuals). The amygdalae were defined as seed regions given that resting state functional connectivity in this brain area is under serotonergic control and relates to a broad range of psychiatric phenotypes. We further used bisulfite pyrosequencing to analyze quantitative methylation at 83 CpG sites within a promoter-associated CpG island of SLC6A4 from blood-derived DNA samples. The major finding of this study indicates a positive relation of SLC6A4 promoter methylation and amygdaloid resting state functional coupling with key nodes of the salience network (SN) including the anterior insulae and the dorsal anterior cingulate cortices. Increased intra-network connectivity in the SN is thought to facilitate the detection and subsequent processing of potentially negative stimuli and reflects a core feature of psychopathology. As such, epigenetic changes within the SLC6A4 gene predict connectivity patterns in clinically and behaviorally relevant brain networks which may in turn convey increased disease susceptibility.
authors: Department of Psychology, Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, Dresden, Germany.|Department of Psychology, Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.
authors: Markus
authors: M
authors: Muehlhan
authors: Department of Psychology, Institute of General Psychology, Biopsychology and Methods of Psychology, Technische Universität Dresden, Germany.
authors: Clemens
authors: C
authors: Kirschbaum
authors: Department of Psychology, Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, Dresden, Germany.
authors: Hans-Ulrich
authors: HU
authors: Wittchen
authors: Department of Psychology, Institute of General Psychology, Biopsychology and Methods of Psychology, Technische Universität Dresden, Germany.
authors: Nina
authors: N
authors: Alexander
mesh_terms: D000328:Adult; D000679:Amygdala / Q000502:physiology*; D002540:Cerebral Cortex / Q000502:physiology*; D063132:Connectome / Q000379:methods*; D018899:CpG Islands; D044127:Epigenesis, Genetic / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D011401:Promoter Regions, Genetic; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D055815:Young Adult
chemical_list: C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins
keywords: amygdala; connectivity; epigenetics; fMRI; imaging genetics; methylation; resting state; salience network; serotonin transporter