title: The Dopamine Receptor D5 May Influence Age of Onset: An Exploratory Study on Indo-Caucasoid ADHD Subjects.
abstract: The objective was to investigate contribution of the dopamine receptor 5 (DRD5) gene variants in the symptoms of attention-deficit/hyperactivity disorder (ADHD) probands since brain regions identified to be affected in these group of patients have higher expression of the DRD5 receptor. Out of 22 exonic variants, 19 were monomorphic in the Indo-Caucasoid individuals. rs6283 "C" and rs113828117 "A" exhibited significant higher occurrence in families with ADHD probands. Several haplotypes showed biased occurrence in the probands. Early and late onset groups exhibited significantly different genotypic frequencies. A new G>A substitution was observed in the control samples only. The late onset group exhibited higher scores for hyperactivity as compared to the early onset group. The authors infer that the age of onset of ADHD may at least partially be affected by DRD5 variants warranting further investigation on the role of DRD5 in the disease etiology.
authors.affiliation: Manovikas Biomedical Research and Diagnostic Centre, Kolkata, India.
authors.forename: Subhamita
authors.initials: S
authors.lastname: Maitra
authors.affiliation: Manovikas Biomedical Research and Diagnostic Centre, Kolkata, India Department of Biotechnology, DOABA College, Jalandhar, Panjab, India.
authors.forename: Kanyakumarika
authors.initials: K
authors.lastname: Sarkar
authors.affiliation: Manovikas Biomedical Research and Diagnostic Centre, Kolkata, India.
authors.forename: Swagata
authors.initials: S
authors.lastname: Sinha
authors.affiliation: Manovikas Biomedical Research and Diagnostic Centre, Kolkata, India kanchanmvk@yahoo.com.
authors.forename: Kanchan
authors.initials: K
authors.lastname: Mukhopadhyay
mesh_terms: D017668:Age of Onset; D001289:Attention Deficit Disorder with Hyperactivity / Q000208:ethnology / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D058068:Endophenotypes; D005091:Exons; D005260:Female; D020022:Genetic Predisposition to Disease; D006239:Haplotypes; D006801:Humans; D007194:India; D008297:Male; D020641:Polymorphism, Single Nucleotide; D050641:Receptors, Dopamine D5 / Q000235:genetics*; D012720:Severity of Illness Index; D044465:White People / Q000235:genetics
chemical_list: C493605:DRD5 protein, human; D050641:Receptors, Dopamine D5
keywords: ADHD; DRD5; rs113828117; rs1800762; rs6283