Genetic and functional analyses of SHANK2 mutations suggest a multiple hit model of autism spectrum disorders.
PLoS Genet
; 8(2): e1002521, 2012 Feb.
Article
en En
| MEDLINE
| ID: mdl-22346768
Autism spectrum disorders (ASD) are a heterogeneous group of neurodevelopmental disorders with a complex inheritance pattern. While many rare variants in synaptic proteins have been identified in patients with ASD, little is known about their effects at the synapse and their interactions with other genetic variations. Here, following the discovery of two de novo SHANK2 deletions by the Autism Genome Project, we identified a novel 421 kb de novo SHANK2 deletion in a patient with autism. We then sequenced SHANK2 in 455 patients with ASD and 431 controls and integrated these results with those reported by Berkel et al. 2010 (nâ=â396 patients and nâ=â659 controls). We observed a significant enrichment of variants affecting conserved amino acids in 29 of 851 (3.4%) patients and in 16 of 1,090 (1.5%) controls (Pâ=â0.004, ORâ=â2.37, 95% CIâ=â1.23-4.70). In neuronal cell cultures, the variants identified in patients were associated with a reduced synaptic density at dendrites compared to the variants only detected in controls (Pâ=â0.0013). Interestingly, the three patients with de novo SHANK2 deletions also carried inherited CNVs at 15q11-q13 previously associated with neuropsychiatric disorders. In two cases, the nicotinic receptor CHRNA7 was duplicated and in one case the synaptic translation repressor CYFIP1 was deleted. These results strengthen the role of synaptic gene dysfunction in ASD but also highlight the presence of putative modifier genes, which is in keeping with the "multiple hit model" for ASD. A better knowledge of these genetic interactions will be necessary to understand the complex inheritance pattern of ASD.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Sinapsis
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Trastornos Generalizados del Desarrollo Infantil
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Eliminación de Secuencia
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Proteínas del Tejido Nervioso
Límite:
Adult
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Child
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Child, preschool
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Female
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Humans
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Male
Idioma:
En
Revista:
PLoS Genet
Asunto de la revista:
GENETICA
Año:
2012
Tipo del documento:
Article
País de afiliación:
Francia
Pais de publicación:
Estados Unidos