title: Autism, regression, and the broader autism phenotype.
abstract: The broader autism phenotype (BAP) is a subclinical set of personality and other features that is thought to index familiality and/or genetic liability to autism. Eighteen parents of autistic probands with a history of language regression and 70 parents of autistic probands without regression were assessed for features of the BAP and compared with published rates in parents of nonautistic subjects. Parents of probands with regressive and nonregressive autism demonstrated similar rates of the BAP (27.8% vs. 32.9%; P = 0.33). The rate of the BAP was significantly higher in both groups of autism parents than in parents of nonautistic subjects (P < or = 0.01). Thus, this measure of genetic liability is increased equally in families with both forms of autism when compared with controls. Environmental events are therefore unlikely to be the sole cause of regressive autism in our sample. Environmental events, however, may act in an additive or "second-hit" fashion in individuals with a genetic vulnerability to autism.
authors.affiliation: Department of Psychiatry, University of Utah, Salt Lake City, UT 84108-1236, USA. janet.lainhart@hsc.utah.edu
authors.forename: Janet E
authors.initials: JE
authors.lastname: Lainhart
authors.forename: Sally
authors.initials: S
authors.lastname: Ozonoff
authors.forename: Hilary
authors.initials: H
authors.lastname: Coon
authors.forename: Lori
authors.initials: L
authors.lastname: Krasny
authors.forename: Elena
authors.initials: E
authors.lastname: Dinh
authors.forename: Julie
authors.initials: J
authors.lastname: Nice
authors.forename: William
authors.initials: W
authors.lastname: McMahon
mesh_terms: D000328:Adult; D001321:Autistic Disorder / Q000235:genetics / Q000503:physiopathology / Q000523:psychology*; D001824:Body Constitution; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D012043:Regression, Psychology