| 1. |
- Jamain, Stéphane, et al.
(författare)
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Linkage and association of the glutamate receptor 6 gene with autism
- 2002
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Ingår i: Molecular Psychiatry. - : Springer Science and Business Media LLC. - 1359-4184 .- 1476-5578. ; 7:3, s. 302-310
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Tidskriftsartikel (refereegranskat)abstract
- A genome scan was previously performed and pointed to chromosome 6q21 as a candidate region for autism. This region contains the glutamate receptor 6 (GluR6 or GRIK2) gene, a functional candidate for the syndrome. Glutamate is the principal excitatory neurotransmitter in the brain and is directly involved in cognitive functions such as memory and learning. We used two different approaches, the affected sib-pair (ASP) method and the transmission disequilibrium test (TDT), to investigate the linkage and association between GluR6 and autism. The ASP method, conducted with additional markers on the 51 original families and in 8 new sibling pairs, showed a significant excess of allele sharing, generating an elevated multipoint maximum LOD score (ASPEX MLS = 3.28). TDT analysis, performed in the ASP families and in an independent data set of 107 parent-offspring trios, indicated a significant maternal transmission disequilibrium (TDTall P = 0.0004). Furthermore, TDT analysis (with only one affected proband per family) showed significant association between GluR6 and autism (TDT association P = 0.008). In contrast to maternal transmission, paternal transmission of GluR6 alleles was as expected in the absence of linkage, suggesting a maternal effect such as imprinting. Mutation screening was performed in 33 affected individuals, revealing several nucleotide polymorphisms (SNPs), including one amino acid change (M867I) in a highly conserved domain of the intracytoplasmic C-terminal region of the protein. This change is found in 8% of the autistic subjects and in 4% of the control population and seems to be more maternally transmitted than expected to autistic males (P = 0.007). Taken together, these data suggest that GluR6 is in linkage disequilibrium with autism.
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| 2. |
- Jamain, Stephane, et al.
(författare)
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Mutations of the X-linked genes encoding neuroligins NLGN3 and NLGN4 are associated with autism
- 2003
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 34:1, s. 27-29
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Tidskriftsartikel (refereegranskat)abstract
- Many studies have supported a genetic etiology for autism. Here we report mutations in two X-linked genes encoding neuroligins NLGN3 and NLGN4 in siblings with autism-spectrum disorders. These mutations affect cell-adhesion molecules localized at the synapse and suggest that a defect of synaptogenesis may predispose to autism.
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| 3. |
- Jamain, Stéphane, et al.
(författare)
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Y chromosome haplogroups in autistic subjects
- 2002
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Ingår i: Molecular Psychiatry. - : Springer Science and Business Media LLC. - 1359-4184 .- 1476-5578. ; 7:2, s. 217-219
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Tidskriftsartikel (refereegranskat)abstract
- The male to female ratio in autism is 4:1 in the global autistic population, but increases to 23:1 in autistic subjects without physical or brain abnormalities. 1 Despite this well-recognised gender difference, male predisposition to autistic disorder remains unexplained and the role of sex chromosomes is still debated. Numerical and structural abnormalities of the sex chromosomes are among the most frequently reported chromosomal disorders associated with autism. However, genome scans have failed to detect linkage on the X chromosome chromosome2–4 and this approach cannot study the non-recombining region of the Y chromosome. In this study, we searched for a specific Y chromosome effect in autistic subjects. Using informative Y-polymorphic markers, the Y chromosome haplotypes of 111 autistic subjects from France, Sweden and Norway were defined and compared with relevant control populations. No significant difference in Y- haplotype distribution between the affected and control groups was observed. Although this study cannot exclude the presence of a Y susceptibility gene, our results are not suggestive of a Y chromosome effect in autism.
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