title: Brief report: non-random X chromosome inactivation in females with autism.
abstract: Autism is a heterogeneous neurodevelopmental disorder with a 3-4 times higher sex ratio in males than females. X chromosome genes may contribute to this higher sex ratio through unusual skewing of X chromosome inactivation. We studied X chromosome skewness in 30 females with classical autism and 35 similarly aged unaffected female siblings as controls using the polymorphic androgen receptor (AR) gene. Significantly, increased X chromosome skewness (e.g., >80:20%) was detected in our autism group (33%) compared to unaffected females (11%). X chromosome skewness was also seen in 50% of the mothers with autistic daughters. No mutation was seen in the promoter region of the XIST gene reported to be involved in X chromosome inactivation in our subjects. X chromosome skewness has been reported in female carriers of other neurological disorders such as X-linked mental retardation, adrenoleukodystrophy and Rett syndrome.
authors.affiliation: Section of Medical Genetics and Molecular Medicine, Children's Mercy Hospitals and Clinics, University of Missouri-Kansas City School of Medicine, MO 64108, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Talebizadeh
authors.forename: D C
authors.initials: DC
authors.lastname: Bittel
authors.forename: O J
authors.initials: OJ
authors.lastname: Veatch
authors.forename: N
authors.initials: N
authors.lastname: Kibiryeva
authors.forename: M G
authors.initials: MG
authors.lastname: Butler
mesh_terms: D001321:Autistic Disorder / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D041321:Chromosomes, Human, X / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D017354:Point Mutation / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated / Q000235:genetics; D049951:X Chromosome Inactivation / Q000235:genetics*
chemical_list: D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; C077885:XIST non-coding RNA