1. Guilmatre A, Dubourg C, Mosca AL, Legallic S, Goldenberg A, Drouin-Garraud V, Layet V, Rosier A, Briault S, Bonnet-Brilhault F, Laumonnier F, Odent S, Le Vacon G, Joly-Helas G, David V, Bendavid C, Pinoit JM, Henry C, Impallomeni C, Germano E, Tortorella G, Di Rosa G, Barthelemy C, Andres C, Faivre L, Frebourg T, Saugier Veber P, Campion D. {{Recurrent rearrangements in synaptic and neurodevelopmental genes and shared biologic pathways in schizophrenia, autism, and mental retardation}}. {Arch Gen Psychiatry};2009 (Sep);66(9):947-956.
CONTEXT: Results of comparative genomic hybridization studies have suggested that rare copy number variations (CNVs) at numerous loci are involved in the cause of mental retardation, autism spectrum disorders, and schizophrenia. OBJECTIVES: To provide an estimate of the collective frequency of a set of recurrent or overlapping CNVs in 3 different groups of cases compared with healthy control subjects and to assess whether each CNV is present in more than 1 clinical category. DESIGN: Case-control study. SETTING: Academic research. PARTICIPANTS: We investigated 28 candidate loci previously identified by comparative genomic hybridization studies for gene dosage alteration in 247 cases with mental retardation, in 260 cases with autism spectrum disorders, in 236 cases with schizophrenia or schizoaffective disorder, and in 236 controls. MAIN OUTCOME MEASURES: Collective and individual frequencies of the analyzed CNVs in cases compared with controls. RESULTS: Recurrent or overlapping CNVs were found in cases at 39.3% of the selected loci. The collective frequency of CNVs at these loci is significantly increased in cases with autism, in cases with schizophrenia, and in cases with mental retardation compared with controls (P < .001, P = .01, and P = .001, respectively, Fisher exact test). Individual significance (P = .02 without correction for multiple testing) was reached for the association between autism and a 350-kilobase deletion located at 22q11 and spanning the PRODH and DGCR6 genes. CONCLUSIONS: Weakly to moderately recurrent CNVs (transmitted or occurring de novo) seem to be causative or contributory factors for these diseases. Most of these CNVs (which contain genes involved in neurotransmission or in synapse formation and maintenance) are present in the 3 pathologic conditions (schizophrenia, autism, and mental retardation), supporting the existence of shared biologic pathways in these neurodevelopmental disorders.
2. Russell G, Kelly S, Golding J. {{A qualitative analysis of lay beliefs about the aetiology and prevalence of autistic spectrum disorders}}. {Child Care Health Dev};2009 (Sep 4)
Abstract Introduction There has been a dramatic increase in the prevalence of autistic spectrum disorders (ASD) in the last 20 years. The reasons for this are disputed. The consensus among epidemiologists and other experts is that greater case load is due to changes in diagnostic practice rather than reflecting changing aetiological factors leading to a true increase in incidence. We set out to examine lay views concerning the aetiology and prevalence of ASD and whether they conflict with or support this consensus position. Methods Over 100 unsolicited communications (letters e mails and several telephone calls) were received by a UK epidemiological study of ASD. We carried out a qualitative analysis of all correspondence in order to examine spontaneously expressed lay beliefs about the prevalence and aetiology of ASD. Results The majority of correspondents suggested theories about environmental causes of ASD. This study demonstrates the strength of lay belief that the true incidence of autism is rising, and this is due to risks from modern technologies and changing lifestyles. Conclusion This study based on unsolicited data highlights the contrast between lay explanations of increasing prevalence and the consensus opinion of medical experts. It also demonstrates how many people in direct contact with ASD have important information to share.
