PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-13 (13)
 

Clipboard (0)
None

Select a Filter Below

Journals
more »
Year of Publication
Document Types
1.  Inherited genetic variants in autism-related CNTNAP2 show perturbed trafficking and ATF6 activation 
Human Molecular Genetics  2012;21(21):4761-4773.
Although genetic variations in several genes encoding for synaptic adhesion proteins have been found to be associated with autism spectrum disorders, one of the most consistently replicated genes has been CNTNAP2, encoding for contactin-associated protein-like 2 (CASPR2), a multidomain transmembrane protein of the neurexin superfamily. Using immunofluorescence confocal microscopy and complementary biochemical techniques, we compared wild-type CASPR2 to 12 point mutations identified in individuals with autism. In contrast to the wild-type protein, localized to the cell surface, some of the mutants show altered cellular disposition. In particular, CASPR2-D1129H is largely retained in the endoplasmic reticulum (ER) in HEK-293 cells and in hippocampal neurons. BiP/Grp78, Calnexin and ERp57, key ER chaperones, appear to be responsible for retention of this mutant and activation of one signaling pathway of the unfolded protein response (UPR). The presence of this mutation also lowers expression and activates proteosomal degradation. A frame-shift mutation that causes a form of syndromic epilepsy (CASPR2-1253*), results in a secreted protein with seemingly normal folding and oligomerization. Taken together, these data indicate that CASPR2-D1129H has severe trafficking abnormalities and CASPR2-1253* is a secreted soluble protein, suggesting that the structural or signaling functions of the membrane tethered form are lost. Our data support a complex genetic architecture in which multiple distinct risk factors interact with others to shape autism risk and presentation.
doi:10.1093/hmg/dds320
PMCID: PMC3471401  PMID: 22872700
2.  SFARI Gene 2.0: a community-driven knowledgebase for the autism spectrum disorders (ASDs) 
Molecular Autism  2013;4:36.
New technologies enabling genome-wide interrogation have led to a large and rapidly growing number of autism spectrum disorder (ASD) candidate genes. Although encouraging, the volume and complexity of these data make it challenging for scientists, particularly non-geneticists, to comprehensively evaluate available evidence for individual genes. Described here is the Gene Scoring module within SFARI Gene 2.0 (https://gene.sfari.org/autdb/GS_Home.do), a platform developed to enable systematic community driven assessment of genetic evidence for individual genes with regard to ASD.
doi:10.1186/2040-2392-4-36
PMCID: PMC3851189  PMID: 24090431
3.  The Disruption of Celf6, a Gene Identified by Translational Profiling of Serotonergic Neurons, Results in Autism-Related Behaviors 
The immense molecular diversity of neurons challenges our ability to understand the genetic and cellular etiology of neuropsychiatric disorders. Leveraging knowledge from neurobiology may help parse the genetic complexity: identifying genes important for a circuit that mediates a particular symptom of a disease may help identify polymorphisms that contribute to risk for the disease as a whole. The serotonergic system has long been suspected in disorders that have symptoms of repetitive behaviors and resistance to change, including autism. We generated a bacTRAP mouse line to permit translational profiling of serotonergic neurons. From this, we identified several thousand serotonergic-cell expressed transcripts, of which 174 were highly enriched, including all known markers of these cells. Analysis of common variants near the corresponding genes in the AGRE collection implicated the RNA binding protein CELF6 in autism risk. Screening for rare variants in CELF6 identified an inherited premature stop codon in one of the probands. Subsequent disruption of Celf6 in mice resulted in animals exhibiting resistance to change and decreased ultrasonic vocalization as well as abnormal levels of serotonin in the brain. This work provides a reproducible and accurate method to profile serotonergic neurons under a variety of conditions and suggests a novel paradigm for gaining information on the etiology of psychiatric disorders.
doi:10.1523/JNEUROSCI.4762-12.2013
PMCID: PMC3711589  PMID: 23407934
4.  Absence of CNTNAP2 leads to epilepsy, neuronal migration abnormalities and core autism-related deficits 
Cell  2011;147(1):235-246.
SUMMARY
Although many genes predisposing to autism spectrum disorders (ASD) have been identified, the biological mechanism(s) remain unclear. Mouse models based on human disease-causing mutations provide the potential for understanding gene function and novel treatment development. Here we characterize a mouse knockout of the Cntnap2 gene, which is strongly associated with ASD and allied neurodevelopmental disorders. Cntnap2−/− mice show deficits in the three core ASD behavioral domains, as well as hyperactivity and epileptic seizures, as has been reported in humans with CNTNAP2 mutations. Neuropathological and physiological analyses of these mice before the onset of seizures reveal neuronal migration abnormalities, reduced number of interneurons and abnormal neuronal network activity. In addition, treatment with the FDA approved drug risperidone, ameliorates the targeted repetitive behaviors in the mutant mice. These data demonstrate a functional role for CNTNAP2 in brain development and provide a new tool for mechanistic and therapeutic research in ASD.
doi:10.1016/j.cell.2011.08.040
PMCID: PMC3390029  PMID: 21962519
5.  A novel approach of homozygous haplotype sharing identifies candidate genes in autism spectrum disorder 
Casey, Jillian P. | Magalhaes, Tiago | Conroy, Judith M. | Regan, Regina | Shah, Naisha | Anney, Richard | Shields, Denis C. | Abrahams, Brett S. | Almeida, Joana | Bacchelli, Elena | Bailey, Anthony J. | Baird, Gillian | Battaglia, Agatino | Berney, Tom | Bolshakova, Nadia | Bolton, Patrick F. | Bourgeron, Thomas | Brennan, Sean | Cali, Phil | Correia, Catarina | Corsello, Christina | Coutanche, Marc | Dawson, Geraldine | de Jonge, Maretha | Delorme, Richard | Duketis, Eftichia | Duque, Frederico | Estes, Annette | Farrar, Penny | Fernandez, Bridget A. | Folstein, Susan E. | Foley, Suzanne | Fombonne, Eric | Freitag, Christine M. | Gilbert, John | Gillberg, Christopher | Glessner, Joseph T. | Green, Jonathan | Guter, Stephen J. | Hakonarson, Hakon | Holt, Richard | Hughes, Gillian | Hus, Vanessa | Igliozzi, Roberta | Kim, Cecilia | Klauck, Sabine M. | Kolevzon, Alexander | Lamb, Janine A. | Leboyer, Marion | Le Couteur, Ann | Leventhal, Bennett L. | Lord, Catherine | Lund, Sabata C. | Maestrini, Elena | Mantoulan, Carine | Marshall, Christian R. | McConachie, Helen | McDougle, Christopher J. | McGrath, Jane | McMahon, William M. | Merikangas, Alison | Miller, Judith | Minopoli, Fiorella | Mirza, Ghazala K. | Munson, Jeff | Nelson, Stanley F. | Nygren, Gudrun | Oliveira, Guiomar | Pagnamenta, Alistair T. | Papanikolaou, Katerina | Parr, Jeremy R. | Parrini, Barbara | Pickles, Andrew | Pinto, Dalila | Piven, Joseph | Posey, David J. | Poustka, Annemarie | Poustka, Fritz | Ragoussis, Jiannis | Roge, Bernadette | Rutter, Michael L. | Sequeira, Ana F. | Soorya, Latha | Sousa, Inês | Sykes, Nuala | Stoppioni, Vera | Tancredi, Raffaella | Tauber, Maïté | Thompson, Ann P. | Thomson, Susanne | Tsiantis, John | Van Engeland, Herman | Vincent, John B. | Volkmar, Fred | Vorstman, Jacob A. S. | Wallace, Simon | Wang, Kai | Wassink, Thomas H. | White, Kathy | Wing, Kirsty | Wittemeyer, Kerstin | Yaspan, Brian L. | Zwaigenbaum, Lonnie | Betancur, Catalina | Buxbaum, Joseph D. | Cantor, Rita M. | Cook, Edwin H. | Coon, Hilary | Cuccaro, Michael L. | Geschwind, Daniel H. | Haines, Jonathan L. | Hallmayer, Joachim | Monaco, Anthony P. | Nurnberger, John I. | Pericak-Vance, Margaret A. | Schellenberg, Gerard D. | Scherer, Stephen W. | Sutcliffe, James S. | Szatmari, Peter | Vieland, Veronica J. | Wijsman, Ellen M. | Green, Andrew | Gill, Michael | Gallagher, Louise | Vicente, Astrid | Ennis, Sean
Human Genetics  2011;131(4):565-579.
Autism spectrum disorder (ASD) is a highly heritable disorder of complex and heterogeneous aetiology. It is primarily characterized by altered cognitive ability including impaired language and communication skills and fundamental deficits in social reciprocity. Despite some notable successes in neuropsychiatric genetics, overall, the high heritability of ASD (~90%) remains poorly explained by common genetic risk variants. However, recent studies suggest that rare genomic variation, in particular copy number variation, may account for a significant proportion of the genetic basis of ASD. We present a large scale analysis to identify candidate genes which may contain low-frequency recessive variation contributing to ASD while taking into account the potential contribution of population differences to the genetic heterogeneity of ASD. Our strategy, homozygous haplotype (HH) mapping, aims to detect homozygous segments of identical haplotype structure that are shared at a higher frequency amongst ASD patients compared to parental controls. The analysis was performed on 1,402 Autism Genome Project trios genotyped for 1 million single nucleotide polymorphisms (SNPs). We identified 25 known and 1,218 novel ASD candidate genes in the discovery analysis including CADM2, ABHD14A, CHRFAM7A, GRIK2, GRM3, EPHA3, FGF10, KCND2, PDZK1, IMMP2L and FOXP2. Furthermore, 10 of the previously reported ASD genes and 300 of the novel candidates identified in the discovery analysis were replicated in an independent sample of 1,182 trios. Our results demonstrate that regions of HH are significantly enriched for previously reported ASD candidate genes and the observed association is independent of gene size (odds ratio 2.10). Our findings highlight the applicability of HH mapping in complex disorders such as ASD and offer an alternative approach to the analysis of genome-wide association data.
Electronic supplementary material
The online version of this article (doi:10.1007/s00439-011-1094-6) contains supplementary material, which is available to authorized users.
doi:10.1007/s00439-011-1094-6
PMCID: PMC3303079  PMID: 21996756
6.  Language-related Cntnap2 gene is differentially expressed in sexually dimorphic song nuclei essential for vocal learning in songbirds 
The Journal of comparative neurology  2010;518(11):1995-2018.
Multiple studies, involving distinct clinical populations, implicate contactin associated protein-like 2 (CNTNAP2) in aspects of language development and performance. While CNTNAP2 is broadly distributed in developing rodent brain, it shows a striking gradient of frontal cortical enrichment in developing human brain, consistent with a role in patterning circuits that subserve higher cognition and language. To test the hypothesis that CNTNAP2 may be important for learned vocal communication in additional species, we employed in situ hybridization to characterize transcript distribution in the zebra finch, an experimentally tractable songbird for which the neural substrate of this behavior is well-established. Consistent with an important role in learned vocalization, Cntnap2 was enriched or diminished in key song control nuclei relative to adjacent brain tissue. Importantly, this punctuated expression was observed in males, but not females, in accord with the sexual dimorphism of neural circuitry and vocal learning in this species. Ongoing functional work will provide important insights into the relationship between Cntnap2 and vocal communication in songbirds and thereby clarify mechanisms at play in disorders of human cognition and language.
doi:10.1002/cne.22318
PMCID: PMC2864722  PMID: 20394055
autism; avian; birdsong; CASPR2; contactin; neurexin; zebra finch
7.  Altered Functional Connectivity in Frontal Lobe Circuits Is Associated with Variation in the Autism Risk Gene CNTNAP2 
Science translational medicine  2010;2(56):56ra80.
Genetic studies are rapidly identifying variants that shape risk for disorders of human cognition, but the question of how such variants predispose to neuropsychiatric disease remains. Noninvasive human brain imaging allows assessment of the brain in vivo, and the combination of genetics and imaging phenotypes remains one of the only ways to explore functional genotype-phenotype associations in human brain. Common variants in contactin-associated protein-like 2 (CNTNAP2), a neurexin superfamily member, have been associated with several allied neurodevelopmental disorders, including autism and specific language impairment, and CNTNAP2 is highly expressed in frontal lobe circuits in the developing human brain. Using functional neuroimaging, we have demonstrated a relationship between frontal lobar connectivity and common genetic variants in CNTNAP2. These data provide a mechanistic link between specific genetic risk for neurodevelopmental disorders and empirical data implicating dysfunction of long-range connections within the frontal lobe in autism. The convergence between genetic findings and cognitive-behavioral models of autism provides evidence that genetic variation at CNTNAP2 predisposes to diseases such asautism in part through modulation of frontal lobe connectivity.
doi:10.1126/scitranslmed.3001344
PMCID: PMC3065863  PMID: 21048216
8.  Functional Impact of Global Rare Copy Number Variation in Autism Spectrum Disorder 
Pinto, Dalila | Pagnamenta, Alistair T. | Klei, Lambertus | Anney, Richard | Merico, Daniele | Regan, Regina | Conroy, Judith | Magalhaes, Tiago R. | Correia, Catarina | Abrahams, Brett S. | Almeida, Joana | Bacchelli, Elena | Bader, Gary D. | Bailey, Anthony J. | Baird, Gillian | Battaglia, Agatino | Berney, Tom | Bolshakova, Nadia | Bölte, Sven | Bolton, Patrick F. | Bourgeron, Thomas | Brennan, Sean | Brian, Jessica | Bryson, Susan E. | Carson, Andrew R. | Casallo, Guillermo | Casey, Jillian | Cochrane, Lynne | Corsello, Christina | Crawford, Emily L. | Crossett, Andrew | Dawson, Geraldine | de Jonge, Maretha | Delorme, Richard | Drmic, Irene | Duketis, Eftichia | Duque, Frederico | Estes, Annette | Farrar, Penny | Fernandez, Bridget A. | Filipa, Ana | Folstein, Susan E. | Fombonne, Eric | Freitag, Christine M. | Gilbert, John | Gillberg, Christopher | Glessner, Joseph T. | Goldberg, Jeremy | Green, Andrew | Green, Jonathan | Guter, Stephen J. | Hakonarson, Hakon | Heron, Elizabeth A. | Hill, Matthew | Holt, Richard | Howe, Jennifer L. | Hughes, Gillian | Hus, Vanessa | Igliozzi, Roberta | Kim, Cecilia | Klauck, Sabine M. | Kolevzon, Alexander | Korvatska, Olena | Kustanovich, Vlad | Lajonchere, Clara M. | Lamb, Janine A. | Laskawiec, Magdalena | Leboyer, Marion | Le Couteur, Ann | Leventhal, Bennett L. | Lionel, Anath C. | Liu, Xiao-Qing | Lord, Catherine | Lotspeich, Linda | Lund, Sabata C. | Maestrini, Elena | Mahoney, William | Mantoulan, Carine | Marshall, Christian R. | McConachie, Helen | McDougle, Christopher J. | McGrath, Jane | McMahon, William M. | Merikangas, Alison | Migita, Ohsuke | Minshew, Nancy J. | Mirza, Ghazala K. | Munson, Jeff | Nelson, Stanley F. | Noakes, Carolyn | Noor, Abdul | Nygren, Gudrun | Oliveira, Guiomar | Papanikolaou, Katerina | Parr, Jeremy R. | Parrini, Barbara | Paton, Tara | Pickles, Andrew | Pilorge, Marion | Piven, Joseph | Ponting, Chris P. | Posey, David J. | Poustka, Annemarie | Poustka, Fritz | Prasad, Aparna | Ragoussis, Jiannis | Renshaw, Katy | Rickaby, Jessica | Roberts, Wendy | Roeder, Kathryn | Roge, Bernadette | Rutter, Michael L. | Bierut, Laura J. | Rice, John P. | Consortium, SAGE | Salt, Jeff | Sansom, Katherine | Sato, Daisuke | Segurado, Ricardo | Senman, Lili | Shah, Naisha | Sheffield, Val C. | Soorya, Latha | Sousa, Inês | Stein, Olaf | Stoppioni, Vera | Strawbridge, Christina | Tancredi, Raffaella | Tansey, Katherine | Thiruvahindrapduram, Bhooma | Thompson, Ann P. | Thomson, Susanne | Tryfon, Ana | Tsiantis, John | Van Engeland, Herman | Vincent, John B. | Volkmar, Fred | Wallace, Simon | Wang, Kai | Wang, Zhouzhi | Wassink, Thomas H. | Webber, Caleb | Wing, Kirsty | Wittemeyer, Kerstin | Wood, Shawn | Wu, Jing | Yaspan, Brian L. | Zurawiecki, Danielle | Zwaigenbaum, Lonnie | Buxbaum, Joseph D. | Cantor, Rita M. | Cook, Edwin H. | Coon, Hilary | Cuccaro, Michael L. | Devlin, Bernie | Ennis, Sean | Gallagher, Louise | Geschwind, Daniel H. | Gill, Michael | Haines, Jonathan L. | Hallmayer, Joachim | Miller, Judith | Monaco, Anthony P. | Nurnberger, John I. | Paterson, Andrew D. | Pericak-Vance, Margaret A. | Schellenberg, Gerard D. | Szatmari, Peter | Vicente, Astrid M. | Vieland, Veronica J. | Wijsman, Ellen M. | Scherer, Stephen W. | Sutcliffe, James S. | Betancur, Catalina
Nature  2010;466(7304):368-372.
The autism spectrum disorders (ASDs) are a group of conditions characterized by impairments in reciprocal social interaction and communication, and the presence of restricted and repetitive behaviors1. Individuals with an ASD vary greatly in cognitive development, which can range from above average to intellectual disability (ID)2. While ASDs are known to be highly heritable (~90%)3, the underlying genetic determinants are still largely unknown. Here, we analyzed the genome-wide characteristics of rare (<1% frequency) copy number variation (CNV) in ASD using dense genotyping arrays. When comparing 996 ASD individuals of European ancestry to 1,287 matched controls, cases were found to carry a higher global burden of rare, genic CNVs (1.19 fold, P= 0.012), especially so for loci previously implicated in either ASD and/or intellectual disability (1.69 fold, P= 3.4×10−4). Among the CNVs, there were numerous de novo and inherited events, sometimes in combination in a given family, implicating many novel ASD genes like SHANK2, SYNGAP1, DLGAP2 and the X-linked DDX53-PTCHD1 locus. We also discovered an enrichment of CNVs disrupting functional gene-sets involved in cellular proliferation, projection and motility, and GTPase/Ras signaling. Our results reveal many new genetic and functional targets in ASD that may lead to final connected pathways.
doi:10.1038/nature09146
PMCID: PMC3021798  PMID: 20531469
9.  Common genetic variants on 5p14.1 associate with autism spectrum disorders 
Nature  2009;459(7246):528-533.
Autism spectrum disorders (ASDs) represent a group of childhood neurodevelopmental and neuropsychiatric disorders characterized by deficits in verbal communication, impairment of social interaction, and restricted and repetitive patterns of interests and behaviour. To identify common genetic risk factors underlying ASDs, here we present the results of genome-wide association studies on a cohort of 780 families (3,101 subjects) with affected children, and a second cohort of 1,204 affected subjects and 6,491 control subjects, all of whom were of European ancestry. Six single nucleotide polymorphisms between cadherin 10 (CDH10) and cadherin 9 (CDH9)—two genes encoding neuronal cell-adhesion molecules—revealed strong association signals, with the most significant SNP being rs4307059 (P = 3.4 × 10−8, odds ratio = 1.19). These signals were replicated in two independent cohorts, with combined P values ranging from 7.4 × 10−8 to 2.1 × 10−10. Our results implicate neuronal cell-adhesion molecules in the pathogenesis of ASDs, and represent, to our knowledge, the first demonstration of genome-wide significant association of common variants with susceptibility to ASDs.
doi:10.1038/nature07999
PMCID: PMC2943511  PMID: 19404256
10.  A genome-wide scan for common alleles affecting risk for autism 
Anney, Richard | Klei, Lambertus | Pinto, Dalila | Regan, Regina | Conroy, Judith | Magalhaes, Tiago R. | Correia, Catarina | Abrahams, Brett S. | Sykes, Nuala | Pagnamenta, Alistair T. | Almeida, Joana | Bacchelli, Elena | Bailey, Anthony J. | Baird, Gillian | Battaglia, Agatino | Berney, Tom | Bolshakova, Nadia | Bölte, Sven | Bolton, Patrick F. | Bourgeron, Thomas | Brennan, Sean | Brian, Jessica | Carson, Andrew R. | Casallo, Guillermo | Casey, Jillian | Chu, Su H. | Cochrane, Lynne | Corsello, Christina | Crawford, Emily L. | Crossett, Andrew | Dawson, Geraldine | de Jonge, Maretha | Delorme, Richard | Drmic, Irene | Duketis, Eftichia | Duque, Frederico | Estes, Annette | Farrar, Penny | Fernandez, Bridget A. | Folstein, Susan E. | Fombonne, Eric | Freitag, Christine M. | Gilbert, John | Gillberg, Christopher | Glessner, Joseph T. | Goldberg, Jeremy | Green, Jonathan | Guter, Stephen J. | Hakonarson, Hakon | Heron, Elizabeth A. | Hill, Matthew | Holt, Richard | Howe, Jennifer L. | Hughes, Gillian | Hus, Vanessa | Igliozzi, Roberta | Kim, Cecilia | Klauck, Sabine M. | Kolevzon, Alexander | Korvatska, Olena | Kustanovich, Vlad | Lajonchere, Clara M. | Lamb, Janine A. | Laskawiec, Magdalena | Leboyer, Marion | Le Couteur, Ann | Leventhal, Bennett L. | Lionel, Anath C. | Liu, Xiao-Qing | Lord, Catherine | Lotspeich, Linda | Lund, Sabata C. | Maestrini, Elena | Mahoney, William | Mantoulan, Carine | Marshall, Christian R. | McConachie, Helen | McDougle, Christopher J. | McGrath, Jane | McMahon, William M. | Melhem, Nadine M. | Merikangas, Alison | Migita, Ohsuke | Minshew, Nancy J. | Mirza, Ghazala K. | Munson, Jeff | Nelson, Stanley F. | Noakes, Carolyn | Noor, Abdul | Nygren, Gudrun | Oliveira, Guiomar | Papanikolaou, Katerina | Parr, Jeremy R. | Parrini, Barbara | Paton, Tara | Pickles, Andrew | Piven, Joseph | Posey, David J | Poustka, Annemarie | Poustka, Fritz | Prasad, Aparna | Ragoussis, Jiannis | Renshaw, Katy | Rickaby, Jessica | Roberts, Wendy | Roeder, Kathryn | Roge, Bernadette | Rutter, Michael L. | Bierut, Laura J. | Rice, John P. | Salt, Jeff | Sansom, Katherine | Sato, Daisuke | Segurado, Ricardo | Senman, Lili | Shah, Naisha | Sheffield, Val C. | Soorya, Latha | Sousa, Inês | Stoppioni, Vera | Strawbridge, Christina | Tancredi, Raffaella | Tansey, Katherine | Thiruvahindrapduram, Bhooma | Thompson, Ann P. | Thomson, Susanne | Tryfon, Ana | Tsiantis, John | Van Engeland, Herman | Vincent, John B. | Volkmar, Fred | Wallace, Simon | Wang, Kai | Wang, Zhouzhi | Wassink, Thomas H. | Wing, Kirsty | Wittemeyer, Kerstin | Wood, Shawn | Yaspan, Brian L. | Zurawiecki, Danielle | Zwaigenbaum, Lonnie | Betancur, Catalina | Buxbaum, Joseph D. | Cantor, Rita M. | Cook, Edwin H. | Coon, Hilary | Cuccaro, Michael L. | Gallagher, Louise | Geschwind, Daniel H. | Gill, Michael | Haines, Jonathan L. | Miller, Judith | Monaco, Anthony P. | Nurnberger, John I. | Paterson, Andrew D. | Pericak-Vance, Margaret A. | Schellenberg, Gerard D. | Scherer, Stephen W. | Sutcliffe, James S. | Szatmari, Peter | Vicente, Astrid M. | Vieland, Veronica J. | Wijsman, Ellen M. | Devlin, Bernie | Ennis, Sean | Hallmayer, Joachim
Human Molecular Genetics  2010;19(20):4072-4082.
Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 × 10−8. When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner's curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 × 10−8 threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C.
doi:10.1093/hmg/ddq307
PMCID: PMC2947401  PMID: 20663923
11.  A Functional Genetic Link between Distinct Developmental Language Disorders 
The New England journal of medicine  2008;359(22):2337-2345.
BACKGROUND
Rare mutations affecting the FOXP2 transcription factor cause a monogenic speech and language disorder. We hypothesized that neural pathways downstream of FOXP2 influence more common phenotypes, such as specific language impairment.
METHODS
We performed genomic screening for regions bound by FOXP2 using chromatin immunoprecipitation, which led us to focus on one particular gene that was a strong candidate for involvement in language impairments. We then tested for associations between single-nucleotide polymorphisms (SNPs) in this gene and language deficits in a well-characterized set of 184 families affected with specific language impairment.
RESULTS
We found that FOXP2 binds to and dramatically down-regulates CNTNAP2, a gene that encodes a neurexin and is expressed in the developing human cortex. On analyzing CNTNAP2 polymorphisms in children with typical specific language impairment, we detected significant quantitative associations with nonsense-word repetition, a heritable behavioral marker of this disorder (peak association, P = 5.0×10-5 at SNP rs17236239). Intriguingly, this region coincides with one associated with language delays in children with autism.
CONCLUSIONS
The FOXP2-CNTNAP2 pathway provides a mechanistic link between clinically distinct syndromes involving disrupted language.
doi:10.1056/NEJMoa0802828
PMCID: PMC2756409  PMID: 18987363
12.  Advances in autism genetics: on the threshold of a new neurobiology 
Nature reviews. Genetics  2008;9(5):341-355.
Autism is a heterogeneous syndrome defined by impairments in three core domains: social interaction, language and range of interests. Recent work has led to the identification of several autism susceptibility genes and an increased appreciation of the contribution of de novo and inherited copy number variation. Promising strategies are also being applied to identify common genetic risk variants. Systems biology approaches, including array-based expression profiling, are poised to provide additional insights into this group of disorders, in which heterogeneity, both genetic and phenotypic, is emerging as a dominant theme.
doi:10.1038/nrg2346
PMCID: PMC2756414  PMID: 18414403
13.  Genome-Wide Analyses of Exonic Copy Number Variants in a Family-Based Study Point to Novel Autism Susceptibility Genes 
PLoS Genetics  2009;5(6):e1000536.
The genetics underlying the autism spectrum disorders (ASDs) is complex and remains poorly understood. Previous work has demonstrated an important role for structural variation in a subset of cases, but has lacked the resolution necessary to move beyond detection of large regions of potential interest to identification of individual genes. To pinpoint genes likely to contribute to ASD etiology, we performed high density genotyping in 912 multiplex families from the Autism Genetics Resource Exchange (AGRE) collection and contrasted results to those obtained for 1,488 healthy controls. Through prioritization of exonic deletions (eDels), exonic duplications (eDups), and whole gene duplication events (gDups), we identified more than 150 loci harboring rare variants in multiple unrelated probands, but no controls. Importantly, 27 of these were confirmed on examination of an independent replication cohort comprised of 859 cases and an additional 1,051 controls. Rare variants at known loci, including exonic deletions at NRXN1 and whole gene duplications encompassing UBE3A and several other genes in the 15q11–q13 region, were observed in the course of these analyses. Strong support was likewise observed for previously unreported genes such as BZRAP1, an adaptor molecule known to regulate synaptic transmission, with eDels or eDups observed in twelve unrelated cases but no controls (p = 2.3×10−5). Less is known about MDGA2, likewise observed to be case-specific (p = 1.3×10−4). But, it is notable that the encoded protein shows an unexpectedly high similarity to Contactin 4 (BLAST E-value = 3×10−39), which has also been linked to disease. That hundreds of distinct rare variants were each seen only once further highlights complexity in the ASDs and points to the continued need for larger cohorts.
Author Summary
Autism spectrum disorders (ASDs) are common neurodevelopmental syndromes with a strong genetic component. ASDs are characterized by disturbances in social behavior, impaired verbal and nonverbal communication, as well as repetitive behaviors and/or a restricted range of interests. To identify genes likely to contribute to ASD etiology, we performed high density genotyping in 912 multiplex families from the Autism Genetics Resource Exchange (AGRE) collection and contrasted results to those obtained for 1,488 healthy controls. To enrich for variants most likely to interfere with gene function, we restricted our analyses to deletions and gains encompassing exons. Of the many genomic regions highlighted, 27 were seen to harbor rare variants in cases and not controls, both in the first phase of our analysis, and also in an independent replication cohort comprised of 859 cases and 1,051 controls. More work in a larger number of individuals will be required to determine which of the rare alleles highlighted here are indeed related to the ASDs and how they act to shape risk.
doi:10.1371/journal.pgen.1000536
PMCID: PMC2695001  PMID: 19557195

Results 1-13 (13)