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Gene networks for disorders of social behavior provide the mechanisms critical for identifying therapeutic targets and biomarkers. Large behavioral phenotypic effects of small human deletions make the positive sociality of Williams syndrome (WS) ideal for determining transcriptional networks for social dysfunction currently based on DNA variations for disorders such as autistic spectrum disorder (ASD) and schizophrenia (SCHZ). Consensus on WS networks has been elusive due to the need for larger cohort size, sensitive genome-wide detection and analytic tools. We report a core set of WS network perturbations in a cohort of 58 individuals (34 with typical, 6 atypical deletions and 18 controls). Genome-wide exon-level expression arrays robustly detected changes in differentially expressed gene (DEG) transcripts from WS deleted genes that ranked in the top 11 of 12 122 transcripts, validated by quantitative reverse transcription PCR, RNASeq and western blots. WS DEG’s were strictly dosed in the full but not the atypical deletions that revealed a breakpoint position effect on non-deleted CLIP2, a caveat for current phenotypic mapping based on copy number variants. Network analyses tested the top WS DEG’s role in the dendritic spine, employing GeneMANIA to harmonize WS DEGs with comparable query gene-sets. The results indicate perturbed actin cytoskeletal signaling analogous to the excitatory dendritic spines. Independent protein–protein interaction analyses of top WS DEGs generated a 100-node graph annotated topologically revealing three interacting pathways, MAPK, IGF1-PI3K-AKT-mTOR/insulin and actin signaling at the synapse. The results indicate striking similarity of WS transcriptional networks to genome-wide association study-based ASD and SCHZ risk suggesting common network dysfunction for these disorders of divergent sociality.

High-level cognitive and emotional experience arises from brain activity, but the specific brain substrates for religious and spiritual euphoria remain unclear. We demonstrate using functional magnetic resonance imaging scans in 19 devout Mormons that a recognizable feeling central to their devotional practice was reproducibly associated with activation in nucleus accumbens, ventromedial prefrontal cortex, and frontal attentional regions. Nucleus accumbens activation preceded peak spiritual feelings by 1–3 s and was replicated in four separate tasks. Attentional activation in the anterior cingulate and frontal eye fields was greater in the right hemisphere. The association of abstract ideas and brain reward circuitry may interact with frontal attentional and emotive salience processing, suggesting a mechanism whereby doctrinal concepts may come to be intrinsically rewarding and motivate behavior in religious individuals.

In the Ts65Dn/DnJ mouse model of Down syndrome (DS), hippocampal deficits of learning and memory are the most robust features supporting this mouse as a valid cognitive model of DS. Although dentate gyrus (DG) dysfunction is suggested by excessive GABAergic inhibition, its role in perturbing DG functions in DS is unknown. We hypothesize that in the Ts65Dn/DnJ mouse, the specific role of the DG is disturbed in its support of contextual and spatial information. Support for this hypothesis comes from rats with DG lesions that show similar deficits. In order to test this hypothesis, we have developed a novel series of spontaneous exploratory tasks that emphasize the importance of recognizing spatial and contextual cues and that involve DG function. The results with this exploratory battery show that Ts65Dn/DnJ mice are impaired in DG-dependent short-term recognition tests involving object recognition with contextual cues, in place recognition and in metric distance recognition relative to wild type littermate controls. Further, whereas Ts65Dn/DnJ mice can recognize object novelty in the absence of contextual cues after a 5-min delay, they cannot do so after a delay of 24 h, suggesting a problem with CA1-mediated consolidation. The results also show that Ts65Dn/DnJ mice are not impaired in tasks (object recognition and configural object recognition) that are mediated by the perirhinal cortex (PRh). These results implicate the DG as a specific therapeutic target and the PRh as a potential therapeutic strength for future research to ameliorate learning and memory in DS.

Williams syndrome (WS) offers an exciting model for social neuroscience because its genetic basis is well-defined, and the unique phenotype reflects dimensions of prosocial behaviors. WS is associated with a strong drive to approach strangers, a gregarious personality, heightened social engagement yet difficult peer interactions, high non-social anxiety, unusual bias toward positive affect, and diminished sensitivity to fear. New neurobiological evidence points toward alterations in structure, function, and connectivity of the social brain (amygdala, fusiform face area, orbital-frontal regions). Recent genetic studies implicate gene networks in the WS region with the dysregulation of prosocial neuropeptides. The study of WS has implications for understanding human social development, and may provide insight for translating genetic and neuroendocrine evidence into treatments for disorders of social behavior.

Down Syndrome is the most common genetic cause for intellectual disability, yet the pathophysiology of cognitive impairment in Down Syndrome is unknown. We compared fMRI scans of 15 individuals with Down Syndrome to 14 typically developing control subjects while they viewed 50 min of cartoon video clips. There was widespread increased synchrony between brain regions, with only a small subset of strong, distant connections showing underconnectivity in Down Syndrome. Brain regions showing negative correlations were less anticorrelated and were among the most strongly affected connections in the brain. Increased correlation was observed between all of the distributed brain networks studied, with the strongest internetwork correlation in subjects with the lowest performance IQ. A functional parcellation of the brain showed simplified network structure in Down Syndrome organized by local connectivity. Despite increased interregional synchrony, intersubject correlation to the cartoon stimuli was lower in Down Syndrome, indicating that increased synchrony had a temporal pattern that was not in response to environmental stimuli, but idiosyncratic to each Down Syndrome subject. Short-range, increased synchrony was not observed in a comparison sample of 447 autism vs. 517 control subjects from the Autism Brain Imaging Exchange (ABIDE) collection of resting state fMRI data, and increased internetwork synchrony was only observed between the default mode and attentional networks in autism. These findings suggest immature development of connectivity in Down Syndrome with impaired ability to integrate information from distant brain regions into coherent distributed networks., Highlights • Adjacent brain regions are more synchronized in Down Syndrome. • Distant brain regions show less synchronization in Down Syndrome. • Negatively correlated brain regions are less anticorrelated in Down Syndrome. • Down Syndrome subjects show simplified brain network architecture. • Increased brain synchrony does not reflect a response to environmental stimuli.

© 2016 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Williams syndrome is a genetic neurodevelopmental disorder characterized by an uncommon hypersociability and a mosaic of retained and compromised linguistic and cognitive abilities. Nearly all clinically diagnosed individuals with Williams syndrome lack precisely the same set of genes, with breakpoints in chromosome band 7q11.23 (refs 1, 2, 3, 4, 5). The contribution of specific genes to the neuroanatomical and functional alterations, leading to behavioural pathologies in humans, remains largely unexplored. Here we investigate neural progenitor cells and cortical neurons derived from Williams syndrome and typically developing induced pluripotent stem cells. Neural progenitor cells in Williams syndrome have an increased doubling time and apoptosis compared with typically developing neural progenitor cells. Using an individual with atypical Williams syndrome, we narrowed this cellular phenotype to a single gene candidate, frizzled 9 (FZD9). At the neuronal stage, layer V/VI cortical neurons derived from Williams syndrome were characterized by longer total dendrites, increased numbers of spines and synapses, aberrant calcium oscillation and altered network connectivity. Morphometric alterations observed in neurons from Williams syndrome were validated after Golgi staining of post-mortem layer V/VI cortical neurons. This model of human induced pluripotent stem cells fills the current knowledge gap in the cellular biology of Williams syndrome and could lead to further insights into the molecular mechanism underlying the disorder and the human social brain.

Williams syndrome is a neurological condition associated with high levels of auditory reactivity and emotional expression combined with impaired perception of prosody. Yet, little is currently known about the neural organization of affective auditory processing in individuals with this disorder. The current study examines auditory emotion processing in individuals with Williams syndrome. Hemispheric organization for positive and negative human non-linguistic sound processing was compared in participants with and without the disorder using a dichotic listening paradigm. While controls exhibited an expected right cerebral hemisphere advantage for processing negative sounds, those with Williams syndrome showed the opposite pattern. No differences between the groups emerged for the positive stimuli. The results suggest aberrant processing of negative auditory information in Williams syndrome.

Down syndrome (DS), or trisomy 21, is a common disorder associated with several complex clinical phenotypes. Although several hypotheses have been put forward, it is unclear as to whether particular gene loci on chromosome 21 (HSA21) are sufficient to cause DS and its associated features. Here we present a high-resolution genetic map of DS phenotypes based on an analysis of 30 subjects carrying rare segmental trisomies of various regions of HSA21. By using state-of-the-art genomics technologies we mapped segmental trisomies at exon-level resolution and identified discrete regions of 1.8–16.3 Mb likely to be involved in the development of 8 DS phenotypes, 4 of which are congenital malformations, including acute megakaryocytic leukemia, transient myeloproliferative disorder, Hirschsprung disease, duodenal stenosis, imperforate anus, severe mental retardation, DS-Alzheimer Disease, and DS-specific congenital heart disease (DSCHD). Our DS-phenotypic maps located DSCHD to a DSCR1 and DYRK1A , or APP , in causing several severe DS phenotypes. Our study demonstrates the value of combining advanced genomics with cohorts of rare patients for studying DS, a prototype for the role of copy-number variation in complex disease.

Williams syndrome (WS) is a genetic condition characterized by an overly gregarious personality, including high empathetic concern for others. Although seemingly disparate from the profile of autism spectrum disorder (ASD), both are associated with deficits in social communication/cognition. Notably, the mirror neuron system (MNS) has been implicated in social dysfunction for ASD; yet, the integrity of this network and its association with social functioning in WS remains unknown. Magnetic resonance imaging (MRI) methods were used to examine the structural integrity of the MNS of adults with WS versus typically developing (TD) individuals. The Social Responsiveness Scale (SRS), a tool typically used to screen for social features of ASD, was also employed to assess the relationships between social functioning with the MNS morphology in WS participants. WS individuals showed reduced cortical surface area of MNS substrates yet relatively preserved cortical thickness as compared to TD adults. Increased cortical thickness of the inferior parietal lobule (IPL) was associated with increased deficits in social communication, social awareness, social cognition, and autistic mannerisms. However, social motivation was not related to anatomical features of the MNS. Our findings indicate that social deficits typical to both ASD and WS may be attributed to an aberrant MNS, whereas the unusual social drive marked in WS is subserved by substrates distinct from this network.

Orientation distribution functions (ODFs) are widely used to resolve fiber crossing problems in high angular resolution diffusion imaging (HARDI). The characteristics of the ODFs are often assessed using a visual criterion, although the use of objective criteria is also reported, which are directly borrowed from classic signal and image processing theory because they are intuitive and simple to compute. However, they are not always pertinent for the characterization of ODFs. We propose a more general paradigm for assessing the characteristics of ODFs. The idea consists in regarding an ODF as a three-dimensional (3D) point cloud, projecting the 3D point cloud onto an angle-distance map, constructing an angle-distance matrix, and calculating metrics such as length ratio, separability, and uncertainty. The results from both simulated and real data show that the proposed metrics allow for the assessment of the characteristics of ODFs in a quantitative and relatively complete manner.

Williams syndrome (WS) is a genetic condition characterized by a hypersocial personality and desire to form close relationships, juxtaposed with significant anxieties of non-social events. The neural underpinnings of anxiety in individuals with WS are currently unknown. Aberrations in the anatomical and microstructural integrity of the uncinate fasciculus (UF) have been recently implicated in social and generalized anxiety disorders. Based on these findings, we tested the hypothesis that the reported anxieties in individuals with WS share similar neuropathological correlates. Towards this end, diffusion tensor imaging (DTI) methods were employed to examine the microstructural integrity (fractional anisotropy, mean diffusivity, longitudinal diffusivity) of the UF in 18 WS and 15 typically developing adults (TD). Anxiety and sociability questionnaires were administered to determine associations with DTI indices of UF across groups. Results revealed comparable white matter integrity of the UF across groups, yet elevated subjective experience of anxiety in those with WS. Additionally, sociability and UF microstructural properties were dissociated across both groups. Whereas no relationships were found between DTI indices and anxiety in TD participants, strong negative associations were observed between these constructs in individuals with WS. Findings indicated that increased anxiety manifested by individuals with WS was associated with DTI measures of the UF and may signal structural or possibly physiological aberration involving this tract within the prefrontal-temporal network.

Background The ability to recognize and respond appropriately to threat is critical to survival, and the neural substrates subserving attention to threat may be probed using depictions of media violence. Whether neural responses to potential threat differ in Down syndrome is not known. Methods We performed functional MRI scans of 15 adolescent and adult Down syndrome and 14 typically developing individuals, group matched by age and gender, during 50 min of passive cartoon viewing. Brain activation to auditory and visual features, violence, and presence of the protagonist and antagonist were compared across cartoon segments. fMRI signal from the brain’s dorsal attention network was compared to thematic and violent events within the cartoons between Down syndrome and control samples. Results We found that in typical development, the brain’s dorsal attention network was most active during violent scenes in the cartoons and that this was significantly and specifically reduced in Down syndrome. When the antagonist was on screen, there was significantly less activation in the left medial temporal lobe of individuals with Down syndrome. As scenes represented greater relative threat, the disparity between attentional brain activation in Down syndrome and control individuals increased. There was a reduction in the temporal autocorrelation of the dorsal attention network, consistent with a shortened attention span in Down syndrome. Individuals with Down syndrome exhibited significantly reduced activation in primary sensory cortices, and such perceptual impairments may constrain their ability to respond to more complex social cues such as violence. Conclusions These findings may indicate a relative deficit in emotive perception of violence in Down syndrome, possibly mediated by impaired sensory perception and hypoactivation of medial temporal structures in response to threats, with relative preservation of activity in pro-social brain regions. These findings indicate that specific genetic differences associated with Down syndrome can modulate the brain’s response to violence and other complex emotive ideas. Electronic supplementary material The online version of this article (doi:10.1186/s11689-015-9112-y) contains supplementary material, which is available to authorized users.

We analyzed folding abnormalities in the cerebral cortex of subjects with Williams syndrome (WS), a genetically based developmental disorder, using surface-based analyses applied to structural magnetic resonance imaging data. Surfaces generated from each individual hemisphere were registered to a common atlas target (the PALS-B12 atlas). Maps of sulcal depth (distance from the cerebral hull) were combined across individuals to generate maps of average sulcal depth for WS and control subjects, along with depth-difference maps andt-statistic maps that accounted for within-group variability. Significant structural abnormalities were identified in 33 locations, arranged as 16 bilaterally symmetric pairs plus a lateral temporal region in the right hemisphere. Discrete WS folding abnormalities extended across a broad swath from dorsoposterior to ventroanterior regions of each hemisphere, in cortical areas associated with multiple sensory modalities as well as regions implicated in cognitive and emotional behavior. Hemispheric asymmetry in the temporal cortex is reduced in WS compared with control subjects. These findings provide insights regarding possible developmental mechanisms that give rise to folding abnormalities and to the spectrum of behavioral characteristics associated with WS.

Purpose: Humans with small deletions of chromosome 21 provide important models for understanding the role of dosage-sensitive genes in brain morphogenesis. To identify chromosome 21 genes responsible for defects of the central nervous system, we determined the deleted regions and brain malformations in three unrelated individuals with overlapping partial deletions of chromosome 21. Methods: Fluorescent in situ hybridization and magnetic resonance imaging were used to define the chromosomal structure and structural brain abnormalities present in these three individuals. Results: The regions of chromosome 21 found to be deleted in these individuals were as follows: case 1: KCNJ6 to the telomere; case 2: ITSN1 to the telomere; and case 3: ITSN1 to PCNT2. The abnormalities of brain structure shared by all included microcephaly, pachygyria, polymicrogyria, colpocephaly, hypoplastic corpus callosum and white matter, hypoplastic cerebellum, and enlarged ventricular system. The clinical features in common included mental retardation, microcephaly, facial dysmorphism, and epilepsy (severe in one patient). Conclusion: From analyses of the molecular, cytogenetic, and neuroimaging data from these three individuals, combined with those from previously reported cases, we infer that deletion of an 8.4-Mb region in chromosome band 21q22.2-22.3 (KCNJ6-COL6A2) is associated with cortical dysplasia. We propose that one or more dosage-sensitive genes in this region contributes to cortical development and that deletion of 21q22.2-22.3 should be considered in the diagnosis of mentally retarded patients with facial dysmorphism and cerebral dysplasia.

We identified and mapped an anatomically localized failure of cortical maturation in Williams syndrome (WS), a genetic condition associated with deletion of ∼20 contiguous genes on chromosome 7. Detailed three-dimensional (3D) maps of cortical thickness, based on magnetic resonance imaging (MRI) scans of 164 brain hemispheres, identified a delimited zone of right hemisphere perisylvian cortex that was thicker in WS than in matched controls, despite pervasive gray and white matter deficits and reduced total cerebral volumes. 3D cortical surface models were extracted from 82 T1-weighted brain MRI scans (256 × 192 × 124 volumes) of 42 subjects with genetically confirmed WS (mean ± SD, 29.2 ± 9.0 years of age; 19 males, 23 females) and 40 age-matched healthy controls (27.5 ± 7.4 years of age; 16 males, 24 females). A cortical pattern-matching technique used 72 sulcal landmarks traced on each brain as anchors to align cortical thickness maps across subjects, build group average maps, and identify regions with altered cortical thickness in WS. Cortical models were remeshed in frequency space to compute their fractal dimension (surface complexity) for each hemisphere and lobe. Surface complexity was significantly increased in WS (p< 0.0015 andp< 0.0014 for left and right hemispheres, respectively) and correlated with temporoparietal gyrification differences, classified via Steinmetz criteria. In WS, cortical thickness was increased by 5-10% in a circumscribed right hemisphere perisylvian and inferior temporal zone (p< 0.002). Spatially extended cortical regions were identified with increased complexity and thickness; cortical thickness and complexity were also positively correlated in controls (p< 0.03). These findings visualize cortical zones with altered anatomy in WS, which merit additional study with techniques to assess function and connectivity.

Regions close to human centromeres contain DNA fragments spanning hundreds of kilobases that exhibit a high degree of sequence identity (>95%). Here we report the genomic structure and evolution of a family of four paralogous regions related to a 220-kb genomic fragment present on the long arm of human chromosome 21 (21q22.1). Phylogenetic classification of the paralogous sequences obtained from the draft of the Human Genome Project are in agreement with results from comparative fluorescence in situ hybridization on metaphase chromosomes from human and great apes. The original copy present in 21q22.1 in human was duplicated in great apes after the divergence of the orang-utan and inserted in a pericentromeric region, most likely the ancestor of HSA2q, then disseminated by transposition of a larger fragment to other pericentromeric locations: HSA18p11, HSA13q11 and HSA21q11.1. The degree of dissemination varies among species.

Purpose: To identify the relationship between specific genes and phenotypic features of Williams syndrome. Methods: Subjects were selected based on their deletion status determined by fluorescence in situ hybridization using a panel of 24 BACs and cosmids spanning the region commonly deleted and single gene analysis using Southern blotting. From the cohort of subjects, three had atypical deletions. Physical examinations and cognitive tests were administered to the three subjects and the results were compared to those from a cohort of typical WS subjects. Results: The molecular results indicate smaller deletions for each subject. In all three cases, typical Williams facies were absent and visual spatial abilities were above that of full deletion WS subjects, particularly in the qualitative aspects of visual spatial processing. Conclusions: Combining the molecular analysis with the cognitive results suggest that the genes GTF2IRD1 and GTF2I contribute to deficits on visual spatial functioning.

Purpose: To illustrate the use of bacterial artificial chromosome (BAC) clone panels for molecular cytogenetic analysis of complex chromosome rearrangements (CCRs). Methods: High resolution cytogenetics followed by fluorescence in situ hybridization (FISH) analysis using chromosome band-specific BAC probes, in addition to commercially available probes. Results: High resolution cytogenetics in conjunction with FISH using commercially available probes proved inadequate to resolve problems in characterizing a balanced CCR in the mother of a patient who had inherited an unbalanced form of the CCR. Accurate interpretation of the CCR and the unbalanced rearrangement in the patient as trisomy 7p12.2→p21.3 was accomplished only through use of the BAC clone panel. Conclusion: Use of BAC clone panels can enhance the power of FISH analysis in defining chromosome rearrangements that cannot be resolved by high resolution chromosome analysis.

Purpose: Down syndrome (DS) is a major cause of congenital heart disease (CHD) and the most frequent known cause of atrioventricular septal defects (AVSDs). Molecular studies of rare individuals with CHD and partial duplications of chromosome 21 established a candidate region that included D21S55 through the telomere. We now report human molecular and cardiac data that narrow the DS-CHD region, excluding two candidate regions, and propose DSCAM (Down syndrome cell adhesion molecule) as a candidate gene. Methods: A panel of 19 individuals with partial trisomy 21 was evaluated using quantitative Southern blot dosage analysis and fluorescence in situ hybridization (FISH) with subsets of 32 BACs spanning the region defined by D21S16 (21q11.2) through the telomere. These BACs span the molecular markers D21S55, ERG, ETS2, MX1/2, collagen XVIII and collagen VI A1/A2. Fourteen individuals are duplicated for the candidate region, of whom eight (57%) have the characteristic spectrum of DS-CHD. Results: Combining the results from these eight individuals suggests the candidate region for DS-CHD is demarcated by D21S3 (defined by ventricular septal defect), through PFKL (defined by tetralogy of Fallot). Conclusions: These data suggest that the presence of three copies of gene(s) from the region is sufficient for the production of subsets of DS-CHD. This region does not include genes located near D21S55, previously proposed as a “DS critical region,” or the genes encoding collagens VI and XVIII. Of the potential gene candidates in the narrowed DS-CHD region, DSCAM is notable in that it encodes a cell adhesion molecule, spans more than 840 kb of the candidate region, and is expressed in the heart during cardiac development. Given these properties, we propose DSCAM as a candidate for DS-CHD.

The human genome is by far the largest genome to be sequenced, and its size and complexity present many challenges for sequence assembly. The International Human Genome Sequencing Consortium constructed a map of the whole genome to enable the selection of clones for sequencing and for the accurate assembly of the genome sequence. Here we report the construction of the whole-genome bacterial artificial chromosome (BAC) map and its integration with previous landmark maps and information from mapping efforts focused on specific chromosomal regions. We also describe the integration of sequence data with the map.

Williams syndrome (WMS) is a most compelling model of human cognition, of human genome organization, and of evolution. Due to a deletion in chromosome band 7q11.23, subjects have cardiovascular, connective tissue, and neurode-velopmental deficits. Given the striking peaks and valleys in neurocognition including deficits in visual-spatial and global processing, preserved language and face processing, hypersociability, and heightened affect, the goal of this work has been to identify the genes that are responsible, the cause of the deletion, and its origin in primate evolution. To do this, we have generated an integrated physical, genetic, and transcriptional map of the WMS and flanking regions using multicolor metaphase and interphase fluorescence in situ hybridization (FISH) of bacterial artificial chromosomes (BACs) and P1 artificial chromosomes (PACs), BAC end sequencing, PCR gene marker and microsatellite, large-scale sequencing, cDNA library, and database analyses. The results indicate the genomic organization of the WMS region as two nested duplicated regions flanking a largely single-copy region. There are at least two common deletion breakpoints, one in the centromeric and at least two in the telomeric repeated regions. Clones anchoring the unique to the repeated regions are defined along with three new pseudogene families. Primate studies indicate an evolutionary hot spot for chromosomal inversion in the WMS region. A cognitive phenotypic map of WMS is presented, which combines previous data with five further WMS subjects and three atypical WMS subjects with deletions; two larger (deleted for D7S489L) and one smaller, deleted for genes telomeric to FZD9, through LIMK1, but not WSCR1 or telomeric. The results establish regions and consequent gene candidates for WMS features including mental retardation, hypersociability, and facial features. The approach provides the basis for defining pathways linking genetic underpinnings with the neuroanatomical, functional, and behavioral consequences that result in human cognition.

The protein kinase C (PKC) family has been implicated in the regulation of apoptosis. However, the contribution of individual PKC isozymes to this process is not well understood. We reported amplification of the chromosome 2p21 locus in 28% of thyroid neoplasms, and in the WRO thyroid carcinoma cell line. By positional cloning we identified a rearrangement and amplification of the PKCe gene, that maps to 2p21, in WRO cells. This resulted in the overexpression of a chimeric/truncated PKCe (Tr-PKCe) mRNA, coding for N-terminal amino acids 1–116 of the isozyme fused to an unrelated sequence. Expression of the Tr-PKCe protein in PCCL3 cells inhibited activation-induced translocation of endogenous PKCe, but its kinase activity was unaffected, consistent with a dominant negative effect of the mutant protein on activation-induced translocation of wild-type PKCe and/or displacement of the isozyme to an aberrant subcellular location. Cell lines expressing Tr-PKCe grew to a higher saturation density than controls. Moreover, cells expressing Tr-PKCe were resistant to apoptosis, which was associated with higher Bcl-2 levels, a marked impairment in p53 stabilization, and dampened expression of Bax. These findings point to a role for PKCe in apoptosis-signaling pathways in thyroid cells, and indicate that a naturally occurring PKCe mutant that functions as a dominant negative can block cell death triggered by a variety of stimuli.

The achievements of the human and mouse genome projects provide increasing numbers of genes and phenotype-associated mutations (DeBry and Seldin 1996; Schuler et al. 1996). Linking the normal and mutant forms of the genes with their functions remains one of biology’s great challenges. To do this the DNA sequence must be defined ultimately with respect to the chromosomal location of the genes, a task that is facilitated by the many disease models available for study in the mouse. Although the genetic map of the mouse provides a powerful tool to link mutations and diseases with the genes (Dietrich et al. 1996), cytogenetic analysis is essential to define genes associated with chromosomal rearrangements. Molecular cytogenetic analysis, which has been exploited widely for localizing cloned genes, genomic sequences, and disease-related chromosomal rearrangements in the human, has not proven as useful in murine genetics. Whereas human genes and breakpoints can be rapidly and accurately mapped cytogenetically (X.-N. Chen, S. Mitchell, Z.-G. Sun, D. Noya, S. Ma, G.S. Sekhon, K. Thompson, W.T. Hsu, P. Wong, N. Wang et al., unpubl.), the common morphology and less distinct landmarks of mouse chromosomes have combined with the lack of molecular cytogenetic markers to hamper similar analyses in the mouse. To bridge the gap between molecular and cytological methods, previous studies have developed a number of reagents for mouse chromosome identification. These include whole-chromosome reagents (Breneman et al. 1993; Weier et al. 1994; Rabbitts et al. 1995; Liyanage et al. 1996; Xiao et al. 1996) and cosmid or P1 clones used with repeat-sequence-based alternatives to dye-based banding techniques (Boyle et al. 1990). Additionally, mouse yeast artificial chromosome (YAC) and P1 clones have been used to generate chromosome-specific probes through FISH and DAPI counterstaining (Mongelard et al. 1996; Shi et al. 1997). This report combines the products of the mouse genome project with molecular cytogenetic techniques to generate a new set of reagents, bacterial artificial chromosome (BAC) clones with a subset linked to centromeric and telomeric genetic markers. These serve to identify mouse chromosomes 1–19 and X, to fluorescently tag the ends of their genetic maps, and to define multiple band landmarks on each chromosome with unique BACs. The stability of BAC clones, the ease of BAC DNA purification, and the strong fluorescence in situ hybridization (FISH) signals resulting from the large insert size, make them superior molecular cytogenetic reagents (Korenberg and Chen 1995; X-.N. Chen, S. Mitchell, Z.-G. Sun, D. Noya, S. Ma, G.S. Sekhon, K. Thompson, W.T. Hsu, P. Wong, N. Wang et al., unpubl.). By including BAC clones that span each chromosome and contain markers from the ends of the genetic maps, the collection serves to integrate cytogenetic, genetic, and physical maps. The availability of such probes extends mouse analysis to interphase, and facilitates the rapid definition of chromosomal rearrangements and their associated candidate genes.

Nucleoporins are the main components of nuclear pore complexes (NPCs) involved in nucleo-cytoplasmic transport. Starting with an expressed DNA fragment retrieved by exon trapping from pooled human BAC clones mapped to the short arm of chromosome 5, we identified a human nucleoporin cDNA sequence by PCR from a human testis cDNA library. The coding sequence showed high homology to that of the rat nucleoporin 155 (Nup155) cDNA. FISH analysis with the human BAC clone as probe localized the human NUP155 gene to chromosome band 5p13. Northern analysis showed that the human NUP155 gene was expressed at different levels in all tissues tested. Two species of transcripts were observed with estimated lengths of 5.4 and 4.7 kb, respectively, in concordance with the finding of two alternative polyadenylation sites in the cDNA. The genomic location of the human NUP155 gene suggests a possible role in the mental and developmental retardation associated with hemizygous deletions of the 5p13 region.

Distal mouse Chromosome 16 (Chr. 16) includes a region of conserved linkage with human Chromosome 21 (Chr. 21). Mouse models of Down syndrome based on trisomy of distal Chr. 16 have several phenotypes similar to those seen in human patients and have proven useful for correlating dosage imbalance of specific genes with specific developmental anomalies. The degree to which such findings can be related to Down syndrome depends on how well the conserved synteny is maintained. Twenty-four genes have been mapped in both species and there are no discordancies, but the region could carry hundreds of genes. Comparative sequence represents the ultimate comparative map and will aid in identification of genes and their regulatory sequences. A physical map of the distal 4.5 Mb of Chr. 16 has been assembled as an essential step toward a map of sequence-ready templates. The map consists of 51 YACs and 15 BACs and includes 18 transcripts, 9 of which are mapped for the first time in mouse, and 3 of which are, for the first time, described in either species. YAC fragmentation was used to precisely localize the 49 markers on the map. Comparison of this physical map with that of the corresponding region on Chr. 21 shows conservation not only of gene order but of size in the 3 Mb fromCbr1 to Ets2; distal to Ets2, the human map is expanded.[The sequence data described in this paper have been submitted to GenBank. See Tables 1 and 2 for accession nos.]

Chromosome rearrangements associated with neoplasms provide a rich resource for definition of the pathways of tumorigenesis. The power of comparative genome hybridization (CGH) to identify novel genes depends on the existence of suitable markers, which are lacking throughout most of the genome. We now report a general approach that translates CGH data into higher-resolution genomic-clone data that are then used to define the genes located in aneuploid regions. We used CGH to study 33 thyroid-tumor DNAs and two tumor-cell-line DNAs. The results revealed amplifications of chromosome band 2p21, with less-intense amplification on 2p13, 19q13.1, and 1p36 and with least-intense amplification on 1p34, 1q42, 5q31, 5q33-34, 9q32-34, and 14q32. To define the 2p21 region amplified, a dense array of 373 FISH-mapped chromosome 2 bacterial artificial chromosomes (BACs) was constructed, and 87 of these were hybridized to a tumor-cell line. Four BACs carried genomic DNA that was amplified in these cells. The maximum amplified region was narrowed to 3-6 Mb by multicolor FISH with the flanking BACs, and the minimum amplicon size was defined by a contig of 420 kb. Sequence analysis of the amplified BAC 1D9 revealed a fragment of the gene, encoding protein kinase C epsilon (PKCepsilon), that was then shown to be amplified and rearranged in tumor cells. In summary, CGH combined with a dense mapped resource of BACs and large-scale sequencing has led directly to the definition of PKCepsilon as a previously unmapped candidate gene involved in thyroid tumorigenesis.

Down syndrome (DS), a major cause of mental retardation, is characterized by subtle abnormalities of cortical neuroanatomy, neurochemistry and function. Recent work has shown that chromosome band 21q22 is critical for many of the neurological phenotypes of DS. A gene, DSCAM (Down syndrome cell adhesion molecule), has now been isolated from chromosome band 21q22.2-22.3. Homology searches indicate that the putative DSCAM protein is a novel member of the immunoglobulin (Ig) superfamily that represents a new class of neural cell adhesion molecules. The sequence of cDNAs indicates alternative splicing and predicts two protein isoforms, both containing 10 Ig-C2 domains, with nine at the N-terminus and the tenth located between domains 4 and 5 of the following array of six fibronectin III domains, with or without the following transmembrane and intracellular domains. Northern analyses reveals the transcripts of 9.7, 8.5 and 7.6 kb primarily in brain. These transcripts are differentially expressed in substructures of the adult brain. Tissue in situ hybridization analyses of a mouse homolog of the DSCAM gene revealed broad expression within the nervous system at the time of neuronal differentiation in the neural tube, cortex, hippocampus, medulla, spinal cord and most neural crest-derived tissues. Given its location on chromosome 21, its specific expression in the central nervous system and neural crest, and the homologies to molecules involved in neural migration, differentiation, and synaptic function, we propose that DSCAM is involved in neural differentiation and contributes to the central and peripheral nervous system defects in DS.

We propose a generic method for the statistical analysis of collections of anatomical shape complexes, namely sets of surfaces that were previously segmented and labeled in a group of subjects. The method estimates an anatomical model, the template complex, that is representative of the population under study. Its shape reflects anatomical invariants within the dataset. In addition, the method automatically places control points near the most variable parts of the template complex. Vectors attached to these points are parameters of deformations of the ambient 3D space. These deformations warp the template to each subject's complex in a way that preserves the organization of the anatomical structures. Multivariate statistical analysis is applied to these deformation parameters to test for group differences. Results of the statistical analysis are then expressed in terms of deformation patterns of the template complex, and can be visualized and interpreted. The user needs only to specify the topology of the template complex and the number of control points. The method then automatically estimates the shape of the template complex, the optimal position of control points and deformation parameters. The proposed approach is completely generic with respect to any type of application and well adapted to efficient use in clinical studies, in that it does not require point correspondence across surfaces and is robust to mesh imperfections such as holes, spikes, inconsistent orientation or irregular meshing. The approach is illustrated with a neuroimaging study of Down syndrome (DS). The results demonstrate that the complex of deep brain structures shows a statistically significant shape difference between control and DS subjects. The deformation-based modelingis able to classify subjects with very high specificity and sensitivity, thus showing important generalization capability even given a low sample size. We show that the results remain significant even if the number of control points, and hence the dimension of variables in the statistical model, are drastically reduced. The analysis may even suggest that parsimonious models have an increased statistical performance. The method has been implemented in the software Deformetrica, which is publicly available at www.deformetrica.org.

The cDNA sequence of the human chondroadherin gene was cloned using PCR-based techniques. The gene encodes a protein of 359 amino acids, of which the first 21 amino acids represent a putative signal peptide sequence and which possesses 11 leucine-rich repeats flanked by cysteine-rich regions. The cDNA possesses a 5' untranslated region of 149 bp, a coding region of 1080 bp including the stop codon, and a 3' untranslated region of 561 bp terminating in a poly(A) tail. The cDNA hybridizes with a single messenger RNA of 1.9 kb, which is present in chondrocytes at all ages. Analysis of genomic DNA revealed that the chondroadherin gene possesses two introns, both of which reside within the coding region. The first intron has a length of about 2.3 kb and separates the codons for lysine(258) and phenylalanine(259). The second intron has a length of about 0.5 kb and splits the codon for tryptophan(314). This genomic organization results in exon 1 encoding the signal peptide, the amino-terminal cysteine-rich region, and the first 9 leucine-rich repeats; exon 2 encoding the last 2 leucine-rich repeats and part of the carboxy-terminal cysteine-rich region; and exon 3 encoding the remainder of the carboxy-terminal cysteine-rich region. The gene does not possess a TATA box prior to its transcription start site. Isolation of a cosmid clone spanning the chondroadherin gene enabled its chromosome location to be established. The gene was shown to reside at chromosome 17q21.33.

Neogenin was first identified in the chick embryo, and like a number of cell surface proteins of the immunoglobulin (Ig) superfamily, including N-CAM and L1 (generally called cell adhesion molecules or CAMs), it is expressed on growing nerve cells in the developing nervous system of vertebrate embryos. Neogenin is also expressed in other embryonic tissues, suggesting a more general role in developmental processes such as tissue growth regulation, cell-cell recognition, and cell migration. Neogenin, unlike the CAMs, is closely related to a unique tumor suppressor candidate molecule, deleted in colorectal carcinoma (DCC). Like DCC, the neogenin protein consists of four immunoglobulin-like (Ig-like) domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. We now report the cloning and sequencing of cDNA clones coding for the human neogenin protein. Human neogenin shares 87% identity with its chicken homolog, and like its chicken counterpart it is expressed in at least two different isoforms derived from alternative splicing in the intracellular domain. Northern blot analysis revealed two mRNA species of about 5 and 7 kb. The chromosomal location of the human neogenin gene (HGMW-approved symbol NEO1) was determined as 15q22.3-q23, using fluorescence in situ hybridization. The gene therefore maps in the vicinity of a locus associated with Bardet-Biedl syndrome. The identification of human neogenin and its chromosomal location provides a basis for studying its involvement in genetic disorders or diseases.

Chromosome 21 is a model for the study of human chromosomal aneuploidy, and the construction of its physical and transcriptional maps is a necessary step in understanding the molecular basis of aneuploidy-dependent phenotypes. To identify the gene(s) responsible for Down syndrome congenital heart disease (DS-CHD), we constructed a physical map of the D21S55 to MX1 region. A bacterial artificial chromosome (BAC) library was screened using several YACs spanning the interval, and a P1-derived artificial chromosome (PAC) library was screened using radiolabeled STS PCR products and whole BACs in gap-filling initiatives. FISH confirmed the location of all BAC and PAC clones to 21q22.2-q22.3. Overlaps were established using clone-to-clone Southerns and 24 new STSs, generated from the direct sequencing of BAC and PAC ends, along with 35 preexisting STSs. Approximately 3.5 Mb of the 4- to 5-Mb D21S55 to MX1 interval is covered in 85 BACs and 24 PACs, representing fourfold coverage within the contigs. These BAC and PAC contigs are valuable reagents for isolating the genes for DS-CHD.

Human cDNAs for methionine synthase (5-methyltetrahydrofolate:L-homocysteine S-transmethylase; EC 2.1.1. 13) have been isolated from fetal and adult liver and HepG2 libraries. The cDNAs span 7.2 kilobases (kb) and consist of a 394-base pair upstream untranslated region, a 3795-base pair open reading frame encoding a 1265-residue 140.3-kDa protein, and about 3 kb of 3' region. The deduced protein sequence shares 53 and 63% identity with the Escherichia coli and the presumptive Caenorhabditis elegans proteins, respectively, and contains all residues implicated in B12 binding to the E. coli protein. Several potential polymorphisms and a cryptic splice deletion were detected in the coding region of the cDNAs. A polymorphism that results in a D919G modification in the protein is fairly common in human DNA samples. Northern analyses of poly(A) mRNA indicated two major species of about 8 and 10 kb in human tissues and some minor, partially spliced species. mRNA levels were highest in the pancreas, skeletal muscle, and heart of the adult and in the kidney in the fetus and were low in adult liver. Genomic clones were isolated and the 5' region was analyzed. Exon 1 is preceded by a number of potential promoter sites, including an E box, CAAT boxes, and a GC box, but this region lacks a TATA element. The human methionine synthase gene was localized to chromosome region 1q42.3-43 by in situ hybridization.

In Williams Syndrome (WS), a known genetic deletion results in atypical brain function with strengths in face and language processing. We examined how genetic influences on brain activity change with development. In three studies, event-related potentials (ERPs) from large samples of children, adolescents, and adults with the full genetic deletion for WS were compared to typically developing controls, and two adults with partial deletions for WS. Studies 1 and 2 identified ERP markers of brain plasticity in WS across development. Study 3 suggested that, in adults with partial deletions for WS, specific genes may be differentially implicated in face and language processing.

The gene corresponding to a 55-kDa matrix protein previously described in adult human articular cartilage was characterized by sequencing of genomic clones. The deduced protein sequence corresponds to the recently described matrix protein PRELP. The protein was encoded by messages of 1.7, 4.6, and 6.7 kb, whose relative abundance increased as their size decreased. The message heterogeneity appears to originate from variation in the length of the 3'-untranslated region, with the smallest message being contained within the reported sequence and the larger messages having extended 3'-untranslated regions. Two introns were identified within the genomic sequence encoding the smallest message. The first intron of about 6.7 kb resides 16 nucleotides prior to the translation initiation codon, and the second intron of about 2.6 kb resides 173 nucleotides prior to the translation termination codon. The gene, which encompasses at least 16 kb of genomic DNA, was shown to reside on chromosome 1q32. Primer extension techniques were used to establish that the coding sequence commences 199 bp downstream from the major transcription start site. Analysis of the DNA sequence upstream from the transcription start site reveals the presence of numerous potential transcription factor binding sites, but no CAAT or TATA box. At the message level, gene expression was at a high level in juvenile and adult cartilage, but not in the fetus or neonate. The presence of protein in the cartilage matrix was also much lower in the neonate than in the adult. In noncartilagenous tissues appreciable message levels were observed only in the adult lung.

The neuronal cell adhesion molecule Bravo/Nr-CAM is a cell surface protein of the immunoglobulin (Ig) superfamily and is closely related to the L1/NgCAM and neurofascin molecules, all of which contain six immunoglobulin domains, five fibronectin repeats, a transmembrane region, and an intracellular domain. Chicken Bravo/Nr-CAM has been shown to interact with other cell surface molecules of the Ig superfamily and has been implicated in specific pathfinding roles of axonal growth cones in the developing nervous system. We now report the characterization of cDNA clones encoding the human Bravo/Nr-CAM protein, which, like its chicken homolog, is composed of six V-like Ig domains and five fibronectin type III repeats. The human Bravo/Nr-CAM homolog also contains a transmembrane and intracellular domain, both of which are 100% conserved at the amino acid level compared to its chicken homolog. Overall, the human Bravo/Nr-CAM homolog is 82% identical to the chicken Bravo/Nr-CAM amino acid sequence. Independent cDNAs encoding four different isoforms were also identified, all of which contain alternatively spliced variants around the fifth fibronectin type III repeat, including one isoform that had been previously identified for chicken Bravo/Nr-CAM. Northern blot analysis reveals one mRNA species of approximately 7.0 kb in adult human brain tissue. Fluorescence in situ hybridization maps the gene for human Bravo/Nr-CAM to human chromosome 7q31.1-q31.2. This chromosomal locus has been previously identified as containing a tumor suppressor candidate gene commonly deleted in certain human cancer tissues.

We have created a resource for chromosome 22 consisting of 96 unique, well-characterized Fosmids. The Fosmid vector permits efficient cloning of DNA fragments averaging 40 kb in a single-copy vector based on the F factor of Escherichia coli. We have found that Fosmid clones from human chromosome 22 show remarkable stability and are useful for a wide variety of applications in genome analysis. These 96 clones have been localized by FISH, using high-resolution fluorescent banding and multicolor mapping techniques, and their position on the chromosome was correlated with their content of a number of common repeated sequence elements. We identified a subset of clones likely to contain genes by restriction analysis using the enzymes NotI, MluI, SacII, and BssHII. This collection of cytogenetically anchored clones, representing nearly 7% of the chromosome, is of immediate value for detecting chromosomal rearrangements, for use in gene isolation, and as a framework for physical mapping.

The gene encoding the tight junction (zonula occludens) protein, TJP1, was mapped to human chromosome 15q13 by fluorescence in situ hybridization (FISH) using a cDNA probe. The Jackson Laboratory backcross DNA panel derived from the cross (C57BL/6JEi X SPRET/Ei) F1 females X SPRET/Ei males was used to map the mouse Tjp1 to chromosome 7 near position 30 on the Chromosome Committee Map, a region with conserved homology to human chromosome 15q13. FISH studies on metaphases from patients with the Prader-Willi (PWS) or the Angelman syndrome (AS) showed that TJP1 maps close but distal to the PWS/AS chromosome region. 13 refs., 2 figs.

Understanding of the human genome has been advanced significantly by the development of large DNA fragment libraries. To create a map of chromosome 21q that integrates the physical, cytogenetic, and linkage maps, we have characterized a subset of 127 chromosome 21 yeast artificial chromosome (YAC) clones for size, by pulsed field gel electrophoresis, for chimerism and cytogenetic location, by fluorescence in situ hybridization (FISH), and for sequence-tagged sites (STS) content, by PCR. It was found that 54% generated unique map locations on chromosome 21, and 45% detected sites on other chromosomes, of which 33% likely represented true chimerism. Using a simple algorithm, the data from nonchimeric clones have been combined to generate a size-corrected minimal tiling pathway including 58 chromosome 21q YACs that represent approximately 33 Mb and include 9 gaps. To confirm the resulting order and relationship to the cytogenetic map, the breakpoints from 23 cell lines partially aneuploid for chromosome 21 have been analyzed by quantitative Southern blot dosage analysis and FISH with a subset of the markers. As one way of investigating the relationship of the genetic to the physical map, the genetic map was superimposed on the physical map using a subset of well-defined markers common to both. The results suggest potential hot spots for recombination and/or gaps in the physical map. This integrated map will facilitate the search for the genes responsible for the Down syndrome phenotypes and provide a better understanding of genome organization and chromosome structure.

A human lumican cDNA sequence was derived by polymerase chain reaction techniques from RNA obtained from intestine, placenta, and articular cartilage. A contiguous sequence of 1729 bases was obtained corresponding to an observed message size of 1.8 kilobases (kb). The cDNA sequence consists of an 80-base pair (bp) 5′-untranslated region, a 1014-bp coding sequence, and a 618-bp 3′-untranslated region terminating in a 17-bp poly(A) tail. The deduced lumican protein sequence has 338 amino acids, including a putative 18-residue signal peptide. The human lumican gene was shown to be spread over about 7.5 kb of genomic DNA and to be located on chromosome 12q22. The gene consists of 3 exons separated by introns of 2.2 and 3.5 kb. The shorter 5′-intron resides 21 bases prior to the translation initiation codon, and the 3′-intron resides 152 bases prior to the translation termination codon. The lumican message is expressed at high levels in adult articular chondrocytes but at low levels in the young juvenile. This age-related trend in message level is not, however, common to all tissues in which the lumican gene is expressed. Lumican is present in the extracellular matrix of human articular cartilage at all ages, although its abundance is far greater in the adult. In the adult cartilage lumican exists predominantly in a glycoprotein form lacking keratan sulfate, whereas the juvenile form of the molecule is a proteoglycan.

The genomic organization and nucleotide structure of the human cone photoreceptor cGMP phosphodiesterase alpha'-subunit (alpha'-PDE) gene (PDEA2) as well as its chromosomal localization have been determined. This gene, which spans about 48 kb, consists of 22 exons and codes for an 858-amino-acid protein. The alpha'-PDE gene maps to human chromosome 10q24. Its coding region shows about 90% nucleotide identity and 93% amino acid identity with the corresponding region of the bovine gene. The intron-exon organization of the genes encoding human cone alpha'-PDE and rod beta-PDE are very similar, suggesting that these proteins have a close phylogenetic relationship and probably a common origin.

International audience; Statistical analysis of shapes, performed by constructing an atlas composed of an average model of shapes within a population and associated deformation maps, is a fundamental aspect of medical imaging studies. Usual methods for constructing a shape atlas require point correspondences across subjects, which are difficult in practice. By contrast, methods based on currents do not require correspondence. However, existing atlas construction methods using currents suffer from two limitations. First, the template current is not in the form of a topologically correct mesh, which makes direct analysis on shapes difficult. Second, the deformations are parametrized by vectors at the same location as the normals of the template current which often provides a parametrization that is more dense than required. In this paper, we propose a novel method for constructing shape atlases using currents where topology of the template is preserved and deformation parameters are optimized independently of the shape parameters. We use an L1-type prior that enables us to adaptively compute sparse and low dimensional parameterization of deformations. We show an application of our method for comparing anatomical shapes of patients with Down's syndrome and healthy controls, where the sparse parametrization of diffeomorphisms decreases the parameter dimension by one order of magnitude.

Although individuals with Williams syndrome (WS) typically demonstrate an increased appetitive social drive, their social profile is characterized by dissociations, including socially fearless behavior coupled with anxiousness, and distinct patterns of "peaks and valleys" of ability.The aim of this studywas to compare the processing of social and non-social visually and aurally presented affective stimuli, at the levels of behavior and autonomic nervous system (ANS) responsivity, in individuals with WS contrasted with a typically developing (TD) group, with the viewof elucidating the highly sociable and emotionally sensitive predisposition noted inWS. Behavioral findings supported previous studies of enhanced competence in processing social over non-social stimuli by individuals with WS; however, the patterns of ANS functioning underlying the behavioral performance revealed a surprising profile previously undocumented inWS. Specifically, increased heart rate (HR) reactivity, and a failure for electrodermal activity to habituate were found in individuals with WS contrasted with theTD group, predominantly in response to visual social affective stimuli.Within the auditory domain, greater arousal linked to variation in heart beat periodwas observed in relation to music stimuli in individuals with WS. Taken together, the findings suggest that the pattern of ANS response inWS is more complex than previously noted, with increased arousal to face and music stimuli potentially underpinning the heightened behavioral emotionality to such stimuli. The lack of habituation may underlie the increased affiliation and attraction to faces characterizing individuals with WS. Future research directions are suggested.