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        <title>Molecular Autism - Most accessed articles</title>
        <link>http://www.molecularautism.com</link>
        <description>The most accessed research articles published by Molecular Autism</description>
        <dc:date>2011-12-12T00:00:00Z</dc:date>
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                                <rdf:li rdf:resource="http://www.molecularautism.com/content/2/1/1" />
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        <item rdf:about="http://www.molecularautism.com/content/2/1/15">
        <title>Facial phenotypes in subgroups of pre-pubertal boys with autism spectrum disorders are correlated with clinical phenotypes</title>
        <description>Background:
The brain develops in concert and in coordination with the developing facial tissues, with each influencing the development of the other and sharing genetic signaling pathways. Autism spectrum disorders (ASDs) result from alterations in the embryological brain, suggesting that the development of the faces of children with ASD may result in subtle facial differences compared to typically developing children. In this study, we tested two hypotheses. First, we asked whether children with ASD display a subtle but distinct facial phenotype compared to typically developing children. Second, we sought to determine whether there are subgroups of facial phenotypes within the population of children with ASD that denote biologically discrete subgroups.
Methods:
The 3dMD cranial System was used to acquire three-dimensional stereophotogrammetric images for our study sample of 8- to 12-year-old boys diagnosed with essential ASD (n = 65) and typically developing boys (n = 41) following approved Institutional Review Board protocols. Three-dimensional coordinates were recorded for 17 facial anthropometric landmarks using the 3dMD Patient software. Statistical comparisons of facial phenotypes were completed using Euclidean Distance Matrix Analysis and Principal Coordinates Analysis. Data representing clinical and behavioral traits were statistically compared among groups by using &#967;2 tests, Fisher&apos;s exact tests, Kolmogorov-Smirnov tests and Student&apos;s t-tests where appropriate.
Results:
First, we found that there are significant differences in facial morphology in boys with ASD compared to typically developing boys. Second, we also found two subgroups of boys with ASD with facial morphology that differed from the majority of the boys with ASD and the typically developing boys. Furthermore, membership in each of these distinct subgroups was correlated with particular clinical and behavioral traits.
Conclusions:
Boys with ASD display a facial phenotype distinct from that of typically developing boys, which may reflect alterations in the prenatal development of the brain. Subgroups of boys with ASD defined by distinct facial morphologies correlated with clinical and behavioral traits, suggesting potentially different etiologies and genetic differences compared to the larger group of boys with ASD. Further investigations into genes involved in neurodevelopment and craniofacial development of these subgroups will help to elucidate the causes and significance of these subtle facial differences.</description>
        <link>http://www.molecularautism.com/content/2/1/15</link>
                <dc:creator>Kristina Aldridge</dc:creator>
                <dc:creator>Ian George</dc:creator>
                <dc:creator>Kimberly Cole</dc:creator>
                <dc:creator>Jordan Austin</dc:creator>
                <dc:creator>T Nicole Takahashi</dc:creator>
                <dc:creator>Ye Duan</dc:creator>
                <dc:creator>Judith Miles</dc:creator>
                <dc:source>Molecular Autism 2011, null:15</dc:source>
        <dc:date>2011-10-14T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-2-15</dc:identifier>
                            <dc:title>The face of autism</dc:title>
                            <dc:description>A distinctive facial phenotype in boys with autism, which differs from that of typically developing boys, may reflect alterations in embryologic brain development in children with autism spectrum disorders.</dc:description>
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        <prism:startingPage>15</prism:startingPage>
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        <item rdf:about="http://www.molecularautism.com/content/2/1/1">
        <title>A noise-reduction GWAS analysis implicates altered regulation of neurite outgrowth and guidance in autism</title>
        <description>Background:
Genome-wide Association Studies (GWAS) have proved invaluable for the identification of disease susceptibility genes. However, the prioritization of candidate genes and regions for follow-up studies often proves difficult due to false-positive associations caused by statistical noise and multiple-testing. In order to address this issue, we propose the novel GWAS noise reduction (GWAS-NR) method as a way to increase the power to detect true associations in GWAS, particularly in complex diseases such as autism.
Methods:
GWAS-NR utilizes a linear filter to identify genomic regions demonstrating correlation among association signals in multiple datasets. We used computer simulations to assess the ability of GWAS-NR to detect association against the commonly used joint analysis and Fisher&apos;s methods. Furthermore, we applied GWAS-NR to a family-based autism GWAS of 597 families and a second existing autism GWAS of 696 families from the Autism Genetic Resource Exchange (AGRE) to arrive at a compendium of autism candidate genes. These genes were manually annotated and classified by a literature review and functional grouping in order to reveal biological pathways which might contribute to autism aetiology.
Results:
Computer simulations indicate that GWAS-NR achieves a significantly higher classification rate for true positive association signals than either the joint analysis or Fisher&apos;s methods and that it can also achieve this when there is imperfect marker overlap across datasets or when the closest disease-related polymorphism is not directly typed. In two autism datasets, GWAS-NR analysis resulted in 1535 significant linkage disequilibrium (LD) blocks overlapping 431 unique reference sequencing (RefSeq) genes. Moreover, we identified the nearest RefSeq gene to the non-gene overlapping LD blocks, producing a final candidate set of 860 genes. Functional categorization of these implicated genes indicates that a significant proportion of them cooperate in a coherent pathway that regulates the directional protrusion of axons and dendrites to their appropriate synaptic targets.
Conclusions:
As statistical noise is likely to particularly affect studies of complex disorders, where genetic heterogeneity or interaction between genes may confound the ability to detect association, GWAS-NR offers a powerful method for prioritizing regions for follow-up studies. Applying this method to autism datasets, GWAS-NR analysis indicates that a large subset of genes involved in the outgrowth and guidance of axons and dendrites is implicated in the aetiology of autism.</description>
        <link>http://www.molecularautism.com/content/2/1/1</link>
                <dc:creator>John Hussman</dc:creator>
                <dc:creator>Ren-Hua Chung</dc:creator>
                <dc:creator>Anthony Griswold</dc:creator>
                <dc:creator>James Jaworkski</dc:creator>
                <dc:creator>Daria Salyakina</dc:creator>
                <dc:creator>Deqiong Ma</dc:creator>
                <dc:creator>Ioanna Konidari</dc:creator>
                <dc:creator>Patrice Whitehead</dc:creator>
                <dc:creator>Jeffery Vance</dc:creator>
                <dc:creator>Eden Martin</dc:creator>
                <dc:creator>Michael Cuccaro</dc:creator>
                <dc:creator>John Gilbert</dc:creator>
                <dc:creator>Jonathan Haines</dc:creator>
                <dc:creator>Margaret Pericak-Vance</dc:creator>
                <dc:source>Molecular Autism 2011, null:1</dc:source>
        <dc:date>2011-01-19T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-2-1</dc:identifier>
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        <item rdf:about="http://www.molecularautism.com/content/2/1/18">
        <title>An X-chromosome-wide association study in autism families identifies TBL1X as a novel autism spectrum disorder candidate gene in males</title>
        <description>Background:
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder with a strong genetic component. The skewed prevalence toward males and evidence suggestive of linkage to the X chromosome in some studies suggest the presence of X-linked susceptibility genes in people with ASD.
Methods:
We analyzed genome-wide association study (GWAS) data on the X chromosome in three independent autism GWAS data sets: two family data sets and one case-control data set. We performed meta- and joint analyses on the combined family and case-control data sets. In addition to the meta- and joint analyses, we performed replication analysis by using the two family data sets as a discovery data set and the case-control data set as a validation data set.
Results:
One SNP, rs17321050, in the transducin &#946;-like 1X-linked (TBL1X) gene [OMIM:300196] showed chromosome-wide significance in the meta-analysis (P value = 4.86 &#215; 10-6) and joint analysis (P value = 4.53 &#215; 10-6) in males. The SNP was also close to the replication threshold of 0.0025 in the discovery data set (P = 5.89 &#215; 10-3) and passed the replication threshold in the validation data set (P = 2.56 &#215; 10-4). Two other SNPs in the same gene in linkage disequilibrium with rs17321050 also showed significance close to the chromosome-wide threshold in the meta-analysis.
Conclusions:
TBL1X is in the Wnt signaling pathway, which has previously been implicated as having a role in autism. Deletions in the Xp22.2 to Xp22.3 region containing TBL1X and surrounding genes are associated with several genetic syndromes that include intellectual disability and autistic features. Our results, based on meta-analysis, joint analysis and replication analysis, suggest that TBL1X may play a role in ASD risk.</description>
        <link>http://www.molecularautism.com/content/2/1/18</link>
                <dc:creator>Ren-Hua Chung</dc:creator>
                <dc:creator>Deqiong Ma</dc:creator>
                <dc:creator>Kai Wang</dc:creator>
                <dc:creator>Dale Hedges</dc:creator>
                <dc:creator>James Jaworski</dc:creator>
                <dc:creator>John Gilbert</dc:creator>
                <dc:creator>Michael Cuccaro</dc:creator>
                <dc:creator>Harry Wright</dc:creator>
                <dc:creator>Ruth Abramson</dc:creator>
                <dc:creator>Ioanna Konidari</dc:creator>
                <dc:creator>Patrice Whitehead</dc:creator>
                <dc:creator>Gerard Schellenberg</dc:creator>
                <dc:creator>Hakon Hakonarson</dc:creator>
                <dc:creator>Jonathan Haines</dc:creator>
                <dc:creator>Margaret Pericak-Vance</dc:creator>
                <dc:creator>Eden Martin</dc:creator>
                <dc:source>Molecular Autism 2011, null:18</dc:source>
        <dc:date>2011-11-04T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-2-18</dc:identifier>
                            <dc:title>Novel candidate gene for autism</dc:title>
                            <dc:description>TBL1X, which is part of the Wnt signaling pathway, is identified as a candidate gene for autism spectrum disorder (ASD), in the largest chromosome-wide study of the X chromosome in association with ASD.</dc:description>
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                <prism:publicationName>Molecular Autism</prism:publicationName>
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        <prism:startingPage>18</prism:startingPage>
        <prism:publicationDate>2011-11-04T00:00:00Z</prism:publicationDate>
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        <item rdf:about="http://www.molecularautism.com/content/2/1/10">
        <title>Variation in the human Cannabinoid Receptor (CNR1) gene modulates gaze duration for happy faces</title>
        <description>Background:
From an early age, humans look longer at preferred stimuli and also typically look longer at facial expressions of emotion, particularly happy faces. Atypical gaze patterns towards social stimuli are common in autism spectrum conditions (ASC). However, it is unknown whether gaze fixation patterns have any genetic basis. In this study, we tested whether variations in the cannabinoid receptor 1 (CNR1) gene are associated with gaze duration towards happy faces. This gene was selected because CNR1 is a key component of the endocannabinoid system, which is involved in processing reward, and in our previous functional magnetic resonance imaging (fMRI) study, we found that variations in CNR1 modulate the striatal response to happy (but not disgust) faces. The striatum is involved in guiding gaze to rewarding aspects of a visual scene. We aimed to validate and extend this result in another sample using a different technique (gaze tracking).
Methods:
A total of 30 volunteers (13 males and 17 females) from the general population observed dynamic emotional expressions on a screen while their eye movements were recorded. They were genotyped for the identical four single-nucleotide polymorphisms (SNPs) in the CNR1 gene tested in our earlier fMRI study.
Results:
Two SNPs (rs806377 and rs806380) were associated with differential gaze duration for happy (but not disgust) faces. Importantly, the allelic groups associated with a greater striatal response to happy faces in the fMRI study were associated with longer gaze duration at happy faces.
Conclusions:
These results suggest that CNR1 variations modulate the striatal function that underlies the perception of signals of social reward, such as happy faces. This suggests that CNR1 is a key element in the molecular architecture of perception of certain basic emotions. This may have implications for understanding neurodevelopmental conditions marked by atypical eye contact and facial emotion processing, such as ASC.</description>
        <link>http://www.molecularautism.com/content/2/1/10</link>
                <dc:creator>Bhismadev Chakrabarti</dc:creator>
                <dc:creator>Simon Baron-Cohen</dc:creator>
                <dc:source>Molecular Autism 2011, null:10</dc:source>
        <dc:date>2011-06-29T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-2-10</dc:identifier>
                            <dc:title>Looking at happy faces</dc:title>
                            <dc:description>Variations in the CNR1 gene are associated with how long people look at facial expression of emotion, particularly happy faces; these findings could lead to further understanding of clinical conditions marked by atypical eye contact and facial emotion processing such as autism.</dc:description>
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                <prism:publicationName>Molecular Autism</prism:publicationName>
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        <prism:startingPage>10</prism:startingPage>
        <prism:publicationDate>2011-06-29T00:00:00Z</prism:publicationDate>
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        <item rdf:about="http://www.molecularautism.com/content/2/1/19">
        <title>Increased copy number for methylated maternal 15q duplications leads to changes in gene and protein expression in human cortical samples</title>
        <description>Background:
Duplications of chromosome 15q11-q13 account for ~3% of autism cases. Chromosome 15q11-q13 contains imprinted genes necessary for normal mammalian neurodevelopment controlled by a differentially methylated imprinting center (PWS-IC). Maternal duplications of 15q11-q13 (dup15q) occur as both interstitial duplications (int dup(15)) and isodicentric chromosome 15 (idic15). Over-expression of the maternally expressed gene UBE3A is predicted to be the primary cause of the autistic features associated with dup15q. Previous analysis of two post-mortem dup15q frontal cortical samples showed heterogeneity between the two cases, with one showing levels of GABAA receptor genes, UBE3A, and SNRPN in a manner not predicted by copy number or parental imprint.
Methods:
Postmortem human brain tissue (BA19, extrastriate visual cortex) was obtained from 8 dup15q, 10 idiopathic autism and 21 typical control samples. Quantitative PCR was used to confirm duplication status. Quantitative reverse transcriptase PCR and Western blot analyses were performed to measure 15q11-q13 transcript and protein levels, respectively. Methylation-sensitive high resolution melt curve analysis was performed on brain genomic DNA to identify the maternal:paternal ratio of methylation at PWS-IC.
Results:
Dup15q brain samples showed a higher level of PWS-IC methylation than control or autism samples, indicating that the duplication of 15q was maternal in origin. UBE3A transcript and protein levels were significantly higher in dup15q than control and autism, as expected, although levels were variable and lower than expected based on copy number in some samples. In contrast, this increase in copy number did not result in consistently increased GABRB3 transcript or protein levels for dup15q samples. Furthermore, SNRPN was expected to be unchanged in expression in dup15q because it is expressed from the single unmethylated paternal allele, yet SNRPN levels were significantly reduced in dup15q samples compared to controls. PWS-IC methylation positively correlated with UBE3A and GABRB3, but negatively correlated with SNRPN levels.  Idiopathic autism samples exhibited significantly lower GABRB3 and significantly more variable SNRPN levels compared to controls.
Conclusions:
While these results show that increased UBE3A/UBE3A is a consistent feature of dup15q syndrome, they also suggest that gene expression within 15q11-q13 is not based entirely on copy number but can be influenced by epigenetic mechanisms in brain.</description>
        <link>http://www.molecularautism.com/content/2/1/19</link>
                <dc:creator>Haley Scoles</dc:creator>
                <dc:creator>Nora Urraca</dc:creator>
                <dc:creator>Samuel Chadwick</dc:creator>
                <dc:creator>Lawrence Reiter</dc:creator>
                <dc:creator>Janine LaSalle</dc:creator>
                <dc:source>Molecular Autism 2011, null:19</dc:source>
        <dc:date>2011-12-12T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-2-19</dc:identifier>
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        <prism:startingPage>19</prism:startingPage>
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        <item rdf:about="http://www.molecularautism.com/content/2/1/7">
        <title>Histopathologic characterization of the BTBR mouse model of autistic-like behavior reveals selective changes in neurodevelopmental proteins and adult hippocampal neurogenesis</title>
        <description>Background:
The inbred mouse strain BTBR T+ tf/J (BTBR) exhibits behavioral deficits that mimic the core deficits of autism. Neuroanatomically, the BTBR strain is also characterized by a complete absence of the corpus callosum. The goal of this study was to identify novel molecular and cellular changes in the BTBR mouse, focusing on neuronal, synaptic, glial and plasticity markers in the limbic system as a model for identifying putative molecular and cellular substrates associated with autistic behaviors.
Methods:
Forebrains of 8 to 10-week-old male BTBR and age-matched C57Bl/6J control mice were evaluated by immunohistochemistry using free-floating and paraffin embedded sections. Twenty antibodies directed against antigens specific to neurons, synapses and glia were used. Nissl, Timm and acetylcholinesterase (AchE) stains were performed to assess cytoarchitecture, mossy fibers and cholinergic fiber density, respectively. In the hippocampus, quantitative stereological estimates for the mitotic marker bromodeoxyuridine (BrdU) were performed to determine hippocampal progenitor proliferation, survival and differentiation, and brain-derived neurotrophic factor (BDNF) mRNA was quantified by in situ hybridization. Quantitative image analysis was performed for NG2, doublecortin (DCX), NeuroD, GAD67 and Poly-Sialic Acid Neural Cell Adhesion Molecule (PSA-NCAM).
Results:
In midline structures including the region of the absent corpus callosum of BTBR mice, the myelin markers 2&apos;,3&apos;-cyclic nucleotide 3&apos;-phosphodiesterase (CNPase) and myelin basic protein (MBP) were reduced, and the oligodendrocyte precursor NG2 was increased. MBP and CNPase were expressed in small ectopic white matter bundles within the cingulate cortex. Microglia and astrocytes showed no evidence of gliosis, yet orientations of glial fibers were altered in specific white-matter areas. In the hippocampus, evidence of reduced neurogenesis included significant reductions in the number of doublecortin, PSA-NCAM and NeuroD immunoreactive cells in the subgranular zone of the dentate gyrus, and a marked reduction in the number of 5-bromo-2&apos;-deoxyuridine (BrdU) positive progenitors. Furthermore, a significant and profound reduction in BDNF mRNA was seen in the BTBR dentate gyrus. No significant differences were seen in the expression of AchE, mossy fiber synapses or immunoreactivities of microtubule-associated protein MAP2, parvalbumin and glutamate decarboxylase GAD65 or GAD67 isoforms.
Conclusions:
We documented modest and selective alterations in glia, neurons and synapses in BTBR forebrain, along with reduced neurogenesis in the adult hippocampus. Of all markers examined, the most distinctive changes were seen in the neurodevelopmental proteins NG2, PSA-NCAM, NeuroD and DCX. Our results are consistent with aberrant development of the nervous system in BTBR mice, and may reveal novel substrates to link callosal abnormalities and autistic behaviors. The changes that we observed in the BTBR mice suggest potential novel therapeutic strategies for intervention in autism spectrum disorders.</description>
        <link>http://www.molecularautism.com/content/2/1/7</link>
                <dc:creator>Diane Stephenson</dc:creator>
                <dc:creator>Sharon O'Neill</dc:creator>
                <dc:creator>Sapna Narayan</dc:creator>
                <dc:creator>Aadhya Tiwari</dc:creator>
                <dc:creator>Elizabeth Arnold</dc:creator>
                <dc:creator>Harry Samaroo</dc:creator>
                <dc:creator>Fu Du</dc:creator>
                <dc:creator>Robert Ring</dc:creator>
                <dc:creator>Brian Campbell</dc:creator>
                <dc:creator>Mathew Pletcher</dc:creator>
                <dc:creator>Vidita Vaidya</dc:creator>
                <dc:creator>Daniel Morton</dc:creator>
                <dc:source>Molecular Autism 2011, null:7</dc:source>
        <dc:date>2011-05-16T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-2-7</dc:identifier>
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        <item rdf:about="http://www.molecularautism.com/content/1/1/12">
        <title>Fragile X and autism: Intertwined at the molecular level leading to targeted treatments</title>
        <description>Fragile X syndrome (FXS) is caused by an expanded CGG repeat (&gt; 200 repeats) in the 5&apos; untranslated portion of the fragile mental retardation 1 gene (FMR1), leading to deficiency or absence of the FMR1 protein (FMRP). FMRP is an RNA carrier protein that controls the translation of several other genes that regulate synaptic development and plasticity. Autism occurs in approximately 30% of FXS cases, and pervasive developmental disorder, not otherwise specified (PDD-NOS) occurs in an additional 30% of cases. Premutation repeat expansions (55 to 200 CGG repeats) may also give rise to autism spectrum disorders (ASD), including both autism and PDD-NOS, through a different molecular mechanism that involves a direct toxic effect of the expanded CGG repeat FMR1 mRNA. RNA toxicity can also lead to aging effects including tremor, ataxia and cognitive decline, termed fragile X-associated tremor ataxia syndrome (FXTAS), in premutation carriers in late life. In studies of mice bearing premutation expansions, there is evidence of early postnatal neuronal cell toxicity, presenting as reduced cell longevity, decreased dendritic arborization and altered synaptic morphology. There is also evidence of mitochondrial dysfunction in premutation carriers. Many of the problems with cellular dysregulation in both premutation and full mutation neurons also parallel the cellular abnormalities that have been documented in autism without fragile X mutations. Research regarding dysregulation of neurotransmitter systems in FXS, including the metabotropic glutamate receptor (mGluR)1/5 pathway and &#947; aminobutyric acid (GABA)A pathways, have led to new targeted treatments for FXS. Preliminary evidence suggests that these new targeted treatments will also be beneficial in non-fragile X forms of autism.</description>
        <link>http://www.molecularautism.com/content/1/1/12</link>
                <dc:creator>Randi Hagerman</dc:creator>
                <dc:creator>Gry Hoem</dc:creator>
                <dc:creator>Paul Hagerman</dc:creator>
                <dc:source>Molecular Autism 2010, null:12</dc:source>
        <dc:date>2010-09-21T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-1-12</dc:identifier>
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        <item rdf:about="http://www.molecularautism.com/content/1/1/15">
        <title>Haploinsufficiency of the autism-associated Shank3 gene leads to deficits in synaptic function, social interaction, and social communication</title>
        <description>Background:
SHANK3 is a protein in the core of the postsynaptic density (PSD) and has a critical role in recruiting many key functional elements to the PSD and to the synapse, including components of &#945;-amino-3-hydroxyl-5-methyl-4-isoxazole-propionic acid (AMPA), metabotropic glutamate (mGlu) and N-methyl-D-aspartic acid (NMDA) glutamate receptors, as well as cytoskeletal elements. Loss of a functional copy of the SHANK3 gene leads to the neurobehavioral manifestations of 22q13 deletion syndrome and/or to autism spectrum disorders. The goal of this study was to examine the effects of haploinsufficiency of full-length Shank3 in mice, focusing on synaptic development, transmission and plasticity, as well as on social behaviors, as a model for understanding SHANK3 haploinsufficiency in humans.
Methods:
We used mice with a targeted disruption of Shank3 in which exons coding for the ankyrin repeat domain were deleted and expression of full-length Shank3 was disrupted. We studied synaptic transmission and plasticity by multiple methods, including patch-clamp whole cell recording, two-photon time-lapse imaging and extracellular recordings of field excitatory postsynaptic potentials. We also studied the density of GluR1-immunoreactive puncta in the CA1 stratum radiatum and carried out assessments of social behaviors.
Results:
In Shank3 heterozygous mice, there was reduced amplitude of miniature excitatory postsynaptic currents from hippocampal CA1 pyramidal neurons and the input-output (I/O) relationship at Schaffer collateral-CA1 synapses in acute hippocampal slices was significantly depressed; both of these findings indicate a reduction in basal neurotransmission. Studies with specific inhibitors demonstrated that the decrease in basal transmission reflected reduced AMPA receptor-mediated transmission. This was further supported by the observation of reduced numbers of GluR1-immunoreactive puncta in the stratum radiatum. Long-term potentiation (LTP), induced either with &#952;-burst pairing (TBP) or high-frequency stimulation, was impaired in Shank3 heterozygous mice, with no significant change in long-term depression (LTD). In concordance with the LTP results, persistent expansion of spines was observed in control mice after TBP-induced LTP; however, only transient spine expansion was observed in Shank3 heterozygous mice. Male Shank3 heterozygotes displayed less social sniffing and emitted fewer ultrasonic vocalizations during interactions with estrus female mice, as compared to wild-type littermate controls.
Conclusions:
We documented specific deficits in synaptic function and plasticity, along with reduced reciprocal social interactions in Shank3 heterozygous mice. Our results are consistent with altered synaptic development and function in Shank3 haploinsufficiency, highlighting the importance of Shank3 in synaptic function and supporting a link between deficits in synapse function and neurodevelopmental disorders. The reduced glutamatergic transmission that we observed in the Shank3 heterozygous mice represents an interesting therapeutic target in Shank3-haploinsufficiency syndromes.</description>
        <link>http://www.molecularautism.com/content/1/1/15</link>
                <dc:creator>Ozlem Bozdagi</dc:creator>
                <dc:creator>Takeshi Sakurai</dc:creator>
                <dc:creator>Danae Papapetrou</dc:creator>
                <dc:creator>Xiaobin Wang</dc:creator>
                <dc:creator>Dara Dickstein</dc:creator>
                <dc:creator>Nagahide Takahashi</dc:creator>
                <dc:creator>Yuji Kajiwara</dc:creator>
                <dc:creator>Mu Yang</dc:creator>
                <dc:creator>Adam Katz</dc:creator>
                <dc:creator>Maria Luisa Scattoni</dc:creator>
                <dc:creator>Mark Harris</dc:creator>
                <dc:creator>Roheeni Saxena</dc:creator>
                <dc:creator>Jill Silverman</dc:creator>
                <dc:creator>Jacqueline Crawley</dc:creator>
                <dc:creator>Qiang Zhou</dc:creator>
                <dc:creator>Patrick Hof</dc:creator>
                <dc:creator>Joseph Buxbaum</dc:creator>
                <dc:source>Molecular Autism 2010, null:15</dc:source>
        <dc:date>2010-12-17T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-1-15</dc:identifier>
                            <dc:title>How a genetic mutation may lead to autism</dc:title>
                            <dc:description>Recent discovery may explain how mutations affecting SHANK3 may lead to autism spectrum disorders</dc:description>
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                <prism:publicationName>Molecular Autism</prism:publicationName>
        <prism:issn>2040-2392</prism:issn>
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        <prism:startingPage>15</prism:startingPage>
        <prism:publicationDate>2010-12-17T00:00:00Z</prism:publicationDate>
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    </item>
        <item rdf:about="http://www.molecularautism.com/content/2/1/5">
        <title>Further characterization of autoantibodies to GABAergic neurons in the central nervous system produced by a subset of children with autism</title>
        <description>Background:
Autism is a neurodevelopmental disorder characterized by impairments in social interaction and deficits in verbal and nonverbal communication, together with the presence of repetitive behaviors or a limited repertoire of activities and interests. The causes of autism are currently unclear. In a previous study, we determined that 21% of children with autism have plasma autoantibodies that are immunoreactive with a population of neurons in the cerebellum that appear to be Golgi cells, which are GABAergic interneurons.
Methods:
We have extended this analysis by examining plasma immunoreactivity in the remainder of the brain. To determine cell specificity, double-labeling studies that included one of the calcium-binding proteins that are commonly colocalized in GABAergic neurons (calbindin, parvalbumin or calretinin) were also carried out to determine which GABAergic neurons are immunoreactive. Coronal sections through the rostrocaudal extent of the macaque monkey brain were reacted with plasma from each of seven individuals with autism who had previously demonstrated positive Golgi cell staining, as well as six negative controls. In addition, brain sections from adult male mice were similarly examined.
Results:
In each case, specific staining was observed for neurons that had the morphological appearance of interneurons. By double-labeling sections with plasma and with antibodies directed against &#947;-aminobutyric acid (GABA), we determined that all autoantibody-positive neurons were GABAergic. However, not all GABAergic neurons were autoantibody-positive. Calbindin was colabeled in several of the autoantibody-labeled cells, while parvalbumin colabeling was less frequently observed. Autoantibody-positive cells rarely expressed calretinin. Sections from the mouse brain processed similarly to the primate sections also demonstrated immunoreactivity to interneurons distributed throughout the neocortex and many subcortical regions. Some cell populations stained in the primate (such as the Golgi neurons in the cerebellum) were not as robustly immunoreactive in the mouse brain.
Conclusions:
These results suggest that the earlier report of autoantibody immunoreactivity to specific cells in the cerebellum extend to other regions of the brain. Further, these findings confirm the autoantibody-targeted cells to be a subpopulation of GABAergic interneurons. The potential impact of these autoantibodies on GABAergic disruption with respect to the etiology of autism is discussed herein.</description>
        <link>http://www.molecularautism.com/content/2/1/5</link>
                <dc:creator>Sharifia Wills</dc:creator>
                <dc:creator>Christy Rossi</dc:creator>
                <dc:creator>Jeff Bennett</dc:creator>
                <dc:creator>Veronica Martinez-Cerdeno</dc:creator>
                <dc:creator>Paul Ashwood</dc:creator>
                <dc:creator>David Amaral</dc:creator>
                <dc:creator>Judy Van de Water</dc:creator>
                <dc:source>Molecular Autism 2011, null:5</dc:source>
        <dc:date>2011-04-26T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-2-5</dc:identifier>
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        <prism:issn>2040-2392</prism:issn>
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        <prism:startingPage>5</prism:startingPage>
        <prism:publicationDate>2011-04-26T00:00:00Z</prism:publicationDate>
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                <cc:license rdf:resource="http://creativecommons.org/licenses/by/2.0/" />
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        <item rdf:about="http://www.molecularautism.com/content/2/1/4">
        <title>Review of neuroimaging in Autism Spectrum Disorders: what have we learned and where we go from here</title>
        <description>Autism spectrum disorder (ASD) refers to a syndrome of social communication deficits and repetitive behaviors or restrictive interests. It remains a behaviorally defined syndrome with no reliable biological markers. The goal of this review is to summarize the available neuroimaging data and examine their implication for our understanding of the neurobiology of ASD.Although there is variability in the literature on structural magnetic resonance literature (MRI), there is evidence of volume abnormalities in both grey and white matter, with a suggestion of some region-specific differences. Early brain overgrowth is probably the most replicated finding in a subgroup of people with ASD, and new techniques, such as cortical-thickness measurements and surface morphometry have begun to elucidate in more detail the patterns of abnormalities as they evolve with age, and are implicating specific neuroanatomical or neurodevelopmental processes. Functional MRI and diffusion tensor imaging techniques suggest that such volume abnormalities are associated with atypical functional and structural connectivity in the brain, and researchers have begun to use magnetic resonance spectroscopy (MRS) techniques to explore the neurochemical substrate of such abnormalities. The data from multiple imaging methods suggests that ASD is associated with an atypically connected brain. We now need to further clarify such atypicalities, and start interpreting them in the context of what we already know about typical neurodevelopmental processes including migration and organization of the cortex. Such an approach will allow us to relate imaging findings not only to behavior, but also to genes and their expression, which may be related to such processes, and to further our understanding of the nature of neurobiologic abnormalities in ASD.</description>
        <link>http://www.molecularautism.com/content/2/1/4</link>
                <dc:creator>Evdokia Anagnostou</dc:creator>
                <dc:creator>Margot Taylor</dc:creator>
                <dc:source>Molecular Autism 2011, null:4</dc:source>
        <dc:date>2011-04-18T00:00:00Z</dc:date>
        <dc:identifier>doi:10.1186/2040-2392-2-4</dc:identifier>
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                <prism:publicationName>Molecular Autism</prism:publicationName>
        <prism:issn>2040-2392</prism:issn>
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        <prism:startingPage>4</prism:startingPage>
        <prism:publicationDate>2011-04-18T00:00:00Z</prism:publicationDate>
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                <cc:license rdf:resource="http://creativecommons.org/licenses/by/2.0/" />
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