title: Autism and the X chromosome: no linkage to microsatellite loci detected using the affected sibling pair method.
abstract: The etiology of autism spectrum disorders (ASDs) is poorly understood, although it is clear that genetic factors play a major role. ASDs appear to be a heterogeneous group of disorders, making genetic analysis difficult in the absence of etiologically definable subgroups. The excess of males in the affected population has led to suggestions that an X-linked locus could play a role in the causation of autism or a related pervasive developmental disorder. To examine this, we have investigated the genotypes of 31 families with two or more affected boys, at a series of 16 highly polymorphic loci distributed along the X chromosome with an average interlocus distance of 12 cM, in order to identify regions of significantly increased concordance among pairs of affected brothers. No locus tested showed a significant increase in concordance, supporting findings by others that there are no genes of major effect located on the X chromosome that contribute to increased susceptibility to ASD.
authors.affiliation: Department of Biology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Chris K
authors.initials: CK
authors.lastname: Schutz
authors.forename: Diana
authors.initials: D
authors.lastname: Polley
authors.forename: Paula D
authors.initials: PD
authors.lastname: Robinson
authors.forename: Maryse
authors.initials: M
authors.lastname: Chalifoux
authors.forename: Fabio
authors.initials: F
authors.lastname: Macciardi
authors.forename: Bradley N
authors.initials: BN
authors.lastname: White
authors.forename: Jeanette J A
authors.initials: JJ
authors.lastname: Holden
mesh_terms: D000483:Alleles; D001321:Autistic Disorder / Q000235:genetics*; D002874:Chromosome Mapping; D005260:Female; D008040:Genetic Linkage; D006579:Heterozygote; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D009679:Nuclear Family; D014960:X Chromosome / Q000235:genetics*