Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Case Reports
. 2006 May;43(5):429-34.
doi: 10.1136/jmg.2005.039693. Epub 2006 Mar 23.

An inversion inv(4)(p12-p15.3) in autistic siblings implicates the 4p GABA receptor gene cluster

Affiliations
Case Reports

An inversion inv(4)(p12-p15.3) in autistic siblings implicates the 4p GABA receptor gene cluster

J B Vincent et al. J Med Genet. 2006 May.

Abstract

Introduction: We describe the case of two brothers diagnosed with autism who both carry a paracentic inversion of the short arm of chromosome 4 (46,XY, inv(4)(p12-p15.3)). We have determined that this inversion is inherited from an apparently unaffected mother and unaffected maternal grandfather. Methods/

Results: Using fluorescence in situ hybridisation analysis and Southern blot hybridisation we identified the breakpoints. The proximal breakpoint (4p12) maps to a region containing a cluster of gamma-aminobutyric acid A (GABA(A)) receptor genes, and directly interrupts the GABRG1 gene, the distal-most gene of the cluster. We also identified an insertion/deletion polymorphism for a approximately 2 kb LINE1 (L1) element that occurs within intron 7 of GABRG1. Our genotype analysis amongst autism families indicated that the L1 deletion allele did not show increased transmission to affected individuals. No linkage disequilibrium was evident between the L1 and single nucleotide polymorphisms in adjacent GABA(A) receptor genes on 4p, where a recent study has identified significant association with autism.

Discussion: Despite this, the identification of an inversion breakpoint disrupting GABRG1 provides solid support for the genetic involvement of the short arm of chromosome 4 in the genetic aetiology of autism, and for the hypothesis of disrupted GABA neurotransmission in autism.

PubMed Disclaimer

Conflict of interest statement

Competing interests: none declared

Similar articles

Cited by

References

    1. Gillberg C. Chromosomal disorders and autism. J Autism Dev Disord 199828415–425. - PubMed
    1. Xu J, Zwaigenbaum L, Szatmari P, Scherer S W. Molecular cytogenetics of autism. Curr Genomics 20044347–364.
    1. Lord C, Rutter M, Le Couteur A. Autism Diagnostic Interview‐Revised: a revised version of a diagnostic interview for caregivers of individuals with possible pervasive developmental disorders. J Autism Dev Disord 199424659–685. - PubMed
    1. Lord C, Rutter M, Goode S, Heemsbergen J, Jordan H, Mawhood L, Schopler E. Autism diagnostic observation schedule: a standardized observation of communicative and social behavior. J Autism Dev Disord 198919185–212. - PubMed
    1. A full genome screen for autism with evidence for linkage to a region on chromosome 7q. International Molecular Genetic Study of Autism Consortium. Hum Mol Genet 19987571–578. - PubMed

Publication types

Substances

-