title: Preliminary evidence for association of genetic variants in pri-miR-34b/c and abnormal miR-34c expression with attention deficit and hyperactivity disorder.
abstract: Attention deficit and hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder characterized by impairment to sustain attention and inability to control impulses and activity level. The etiology of ADHD is complex, with an estimated heritability of 70-80%. Under the hypothesis that alterations in the processing or target binding of microRNAs (miRNAs) may result in functional alterations predisposing to ADHD, we explored whether common polymorphisms potentially affecting miRNA-mediated regulation are involved in this psychiatric disorder. We performed a comprehensive association study focused on 134 miRNAs in 754 ADHD subjects and 766 controls and found association between the miR-34b/c locus and ADHD. Subsequently, we provided preliminary evidence for overexpression of the miR-34c-3p mature form in peripheral blood mononuclear cells of ADHD subjects. Next, we tested the effect on gene expression of single-nucleotide polymorphisms within the ADHD-associated region and found that rs4938923 in the promoter of the pri-miR-34b/c tags cis expression quantitative trait loci for both miR-34b and miR-34c and has an impact on the expression levels of 681 transcripts in trans, including genes previously associated with ADHD. This gene set was enriched for miR-34b/c binding sites, functional categories related to the central nervous system, such as axon guidance or neuron differentiation, and serotonin biosynthesis and signaling canonical pathways. Our results provide preliminary evidence for the contribution to ADHD of a functional variant in the pri-miR-34b/c promoter, possibly through dysregulation of the expression of mature forms of miR-34b and miR-34c and some target genes. These data highlight the importance of abnormal miRNA function as a potential epigenetic mechanism contributing to ADHD.
authors: Psychiatric Genetics Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain.|Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors: I
authors: I
authors: Garcia-Martínez
authors: Psychiatric Genetics Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain.|Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.|Biomedical Network Research Centre on Mental Health (CIBERSAM), Madrid, Spain.
authors: C
authors: C
authors: Sánchez-Mora
authors: Psychiatric Genetics Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain.|Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors: M
authors: M
authors: Pagerols
authors: Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.|Biomedical Network Research Centre on Mental Health (CIBERSAM), Madrid, Spain.|Department of Psychiatry and Legal Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors: V
authors: V
authors: Richarte
authors: Psychiatric Genetics Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain.|Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.|Department of Psychiatry and Legal Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors: M
authors: M
authors: Corrales
authors: Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors: C
authors: C
authors: Fadeuilhe
authors: Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.|Centro de Investigación Biomédica en Red de Enfermedades Raras, Madrid, Spain.|Institut de Biomedicina de la Universitat de Barcelona, Barcelona, Spain.|Institut de Recerca Pediàtrica, Hospital Sant Joan de Déu, Esplugues, Barcelona, Spain.
authors: B
authors: B
authors: Cormand
authors: Psychiatric Genetics Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain.|Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.|Biomedical Network Research Centre on Mental Health (CIBERSAM), Madrid, Spain.|Department of Psychiatry and Legal Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors: M
authors: M
authors: Casas
authors: Psychiatric Genetics Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain.|Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.|Biomedical Network Research Centre on Mental Health (CIBERSAM), Madrid, Spain.|Department of Psychiatry and Legal Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors: J A
authors: JA
authors: Ramos-Quiroga
authors: Psychiatric Genetics Unit, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain.|Department of Psychiatry, Hospital Universitari Vall d'Hebron, Barcelona, Spain.|Biomedical Network Research Centre on Mental Health (CIBERSAM), Madrid, Spain.
authors: M
authors: M
authors: Ribasés
mesh_terms: D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D015870:Gene Expression; D005838:Genotype; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D011110:Polymorphism, Genetic; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055815:Young Adult
chemical_list: C522425:MIRN34 microRNA, human; D035683:MicroRNAs