title: Role of Genetics in the Etiology of Autistic Spectrum Disorder: Towards a Hierarchical Diagnostic Strategy.
abstract: Progress in epidemiological, molecular and clinical genetics with the development of new techniques has improved knowledge on genetic syndromes associated with autism spectrum disorder (ASD). The objective of this article is to show the diversity of genetic disorders associated with ASD (based on an extensive review of single-gene disorders, copy number variants, and other chromosomal disorders), and consequently to propose a hierarchical diagnostic strategy with a stepwise evaluation, helping general practitioners/pediatricians and child psychiatrists to collaborate with geneticists and neuropediatricians, in order to search for genetic disorders associated with ASD. The first step is a clinical investigation involving: (i) a child psychiatric and psychological evaluation confirming autism diagnosis from different observational sources and assessing autism severity; (ii) a neuropediatric evaluation examining neurological symptoms and developmental milestones; and (iii) a genetic evaluation searching for dysmorphic features and malformations. The second step involves laboratory and if necessary neuroimaging and EEG studies oriented by clinical results based on clinical genetic and neuropediatric examinations. The identification of genetic disorders associated with ASD has practical implications for diagnostic strategies, early detection or prevention of co-morbidity, specific treatment and follow up, and genetic counseling.
authors.affiliation: Pôle Hospitalo-Universitaire de Psychiatrie de l'Enfant et de l'Adolescent (PHUPEA), University of Rennes 1 and Centre Hospitalier Guillaume Régnier, 35200 Rennes, France. robertcyrille@live.fr.|Service de Génétique Clinique, Centre de Référence Maladies Rares Anomalies du Développement (Centre Labellisé pour les Anomalies du Développement de l'Ouest: CLAD Ouest), Hôpital Sud, Centre Hospitalier Universitaire de Rennes, 35200 Rennes, France. robertcyrille@live.fr.
authors.forename: Cyrille
authors.initials: C
authors.lastname: Robert
authors.affiliation: Service de Génétique Clinique, Centre de Référence Maladies Rares Anomalies du Développement (Centre Labellisé pour les Anomalies du Développement de l'Ouest: CLAD Ouest), Hôpital Sud, Centre Hospitalier Universitaire de Rennes, 35200 Rennes, France. laurent.pasquier@chu-rennes.fr.
authors.forename: Laurent
authors.initials: L
authors.lastname: Pasquier
authors.affiliation: Hospital-University Department of Child and Adolescent Psychiatry, Pitié-Salpétrière Hospital, Paris 6 University, 75013 Paris, France. david.cohen@psl.aphp.fr.
authors.forename: David
authors.initials: D
authors.lastname: Cohen
authors.affiliation: Service de Génétique Clinique, Centre de Référence Maladies Rares Anomalies du Développement (Centre Labellisé pour les Anomalies du Développement de l'Ouest: CLAD Ouest), Hôpital Sud, Centre Hospitalier Universitaire de Rennes, 35200 Rennes, France. Melanie.FRADIN@chu-rennes.fr.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Fradin
authors.affiliation: Division of Child and Adolescent Neuropsychiatry, University Hospital of Siena, 53100 Siena, Italy. r.canitano@ao-siena.toscana.it.
authors.forename: Roberto
authors.initials: R
authors.lastname: Canitano
authors.affiliation: Service de Génétique Clinique, Centre de Référence Maladies Rares Anomalies du Développement (Centre Labellisé pour les Anomalies du Développement de l'Ouest: CLAD Ouest), Hôpital Sud, Centre Hospitalier Universitaire de Rennes, 35200 Rennes, France. Lena.DAMAJ@chu-rennes.fr.
authors.forename: Léna
authors.initials: L
authors.lastname: Damaj
authors.affiliation: Service de Génétique Clinique, Centre de Référence Maladies Rares Anomalies du Développement (Centre Labellisé pour les Anomalies du Développement de l'Ouest: CLAD Ouest), Hôpital Sud, Centre Hospitalier Universitaire de Rennes, 35200 Rennes, France. Sylvie.Odent@chu-rennes.fr.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Odent
authors.affiliation: Pôle Hospitalo-Universitaire de Psychiatrie de l'Enfant et de l'Adolescent (PHUPEA), University of Rennes 1 and Centre Hospitalier Guillaume Régnier, 35200 Rennes, France. s.tordjman@yahoo.fr.|Laboratory of Psychology of Perception, University Paris Descartes, 75270 Paris, France. s.tordjman@yahoo.fr.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Tordjman
mesh_terms: D000067877:Autism Spectrum Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000235:genetics*; D030342:Genetic Diseases, Inborn / Q000453:epidemiology*; D020022:Genetic Predisposition to Disease; D006801:Humans
keywords: autism; child psychiatric and psychological assessment; clinical genetics; genetic disorders; hierarchical diagnostic strategy; neuropediatric evaluation