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Aminoacyl-tRNA synthetases (ARSs) are ubiquitous, ancient enzymes that charge amino acids to cognate tRNA molecules, the essential first step of protein translation. Here, we describe 32 individuals from 21 families, presenting with microcephaly, neurodevelopmental delay, seizures, peripheral neuropathy, and ataxia, with de novo heterozygous and bi-allelic mutations in asparaginyl-tRNA synthetase (NARS1). We demonstrate a reduction in NARS1 mRNA expression as well as in NARS1 enzyme levels and activity in both individual fibroblasts and induced neural progenitor cells (iNPCs). Molecular modeling of the recessive c.1633C>T (p.Arg545Cys) variant shows weaker spatial positioning and tRNA selectivity. We conclude that de novo and bi-allelic mutations in NARS1 are a significant cause of neurodevelopmental disease, where the mechanism for de novo variants could be toxic gain-of-function and for recessive variants, partial loss-of-function.

Background Clinicians commonly advise patients to look away from the needle during vaccinations; however, this recommendation is not evidence based. Aim The aim of this study was to determine whether looking at the needle versus looking away affects pain and fear during vaccinations in adults. Methods This was a pilot randomized two-group parallel trial with university students receiving influenza vaccinations. Participants were stratified according to their initial needle-looking preference and randomly assigned to either look at versus away from the needle. Participants self-reported their pain and fear during vaccination. Results Of the 184 subjects who agreed to participate, 160 were enrolled; 66% were female. A three-way analysis of variance (ANOVA; Looking allocation assignment × Looking preference × Sex) revealed a significant main effect of looking allocation assignment on fear (P = 0.025); those who were randomized to look had higher fear scores than those who were randomized to look away. There was also a significant main effect of looking preference on fear (P

Contains fulltext : 174530.pdf (Publisher’s version ) (Open Access) Copy number variants (CNVs) are major contributors to genomic imbalance disorders. Phenotyping of 137 unrelated deletion and reciprocal duplication carriers of the distal 16p11.2 220 kb BP2-BP3 interval showed that these rearrangements are associated with autism spectrum disorders and mirror phenotypes of obesity/underweight and macrocephaly/microcephaly. Such phenotypes were previously associated with rearrangements of the non-overlapping proximal 16p11.2 600 kb BP4-BP5 interval. These two CNV-prone regions at 16p11.2 are reciprocally engaged in complex chromatin looping, as successfully confirmed by 4C-seq, fluorescence in situ hybridization and Hi-C, as well as coordinated expression and regulation of encompassed genes. We observed that genes differentially expressed in 16p11.2 BP4-BP5 CNV carriers are concomitantly modified in their chromatin interactions, suggesting that disruption of chromatin interplays could participate in the observed phenotypes. We also identified cis- and trans-acting chromatin contacts to other genomic regions previously associated with analogous phenotypes. For example, we uncovered that individuals with reciprocal rearrangements of the trans-contacted 2p15 locus similarly display mirror phenotypes on head circumference and weight. Our results indicate that chromosomal contacts' maps could uncover functionally and clinically related genes.

Studies of genomic copy number variants (CNVs) have identified genes associated with autism spectrum disorder (ASD) and intellectual disability (ID) such as NRXN1, SHANK2, SHANK3 and PTCHD1. Deletions have been reported in PTCHD1 however there has been little information available regarding the clinical presentation of these individuals. Herein we present 23 individuals with PTCHD1 deletions or truncating mutations with detailed phenotypic descriptions. The results suggest that individuals with disruption of the PTCHD1 coding region may have subtle dysmorphic features including a long face, prominent forehead, puffy eyelids and a thin upper lip. They do not have a consistent pattern of associated congenital anomalies or growth abnormalities. They have mild to moderate global developmental delay, variable degrees of ID, and many have prominent behavioral issues. Over 40% of subjects have ASD or ASD-like behaviors. The only consistent neurological findings in our cohort are orofacial hypotonia and mild motor incoordination. Our findings suggest that hemizygous PTCHD1 loss of function causes an X-linked neurodevelopmental disorder with a strong propensity to autistic behaviors. Detailed neuropsychological studies are required to better define the cognitive and behavioral phenotype.

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 behaviours 1. Individuals with an ASD vary greatly in cognitive development, which can range from above average to intellectual disability2. Although ASDs are known to be highly heritable ( ∼90%)3, the underlying genetic determinants are still largely unknown.Hereweanalysed the genome-wide characteristics of rare (

To determine whether postmaturity (gestation41 weeks), small for gestational age (SGA), and other pregnancy and birth complications that may elevate risk for neurodevelopmental disorders, are associated with elevated risk for schizophrenia in 22q11 Deletion Syndrome (22qDS), a genetic subtype of schizophrenia.Antepartum and intrapartum features were examined in 20 adults with 22qDS-schizophrenia and three comparison groups: newborn encephalopathy (n = 164) and healthy newborn controls (n = 400) from Badawi et al.'s (Br Med J 1998, 317: 1549) study, and 16 non-psychotic 22qDS adults (22qDS-NP).Postmaturity (OR 13.0, 95% CI 3.95, 42.77; P0.001) and SGA (OR 3.59, 95% CI 1.23, 10.5; P = 0.03) were more prevalent in 22qDS-SZ than controls. Postmaturity was non-significantly more prevalent in 22qDS-SZ than in newborn encephalopathy (P = 0.06) or 22qDS-NP (P = 0.2). SGA showed similar rates in the two 22qDS groups and newborn encephalopathy, but was more prevalent in 22qDS-NP than controls (P = 0.05).The results suggest that postmaturity may be associated with expression of schizophrenia in a 22qDS subtype of schizophrenia. SGA may be a non-specific marker of neurodevelopmental disturbance.

Fibroblasts from a proband with Ehlers-Danlos syndrome type VII synthesized approximately equal amounts of normal and shortened pro alpha 2(I) chains of type I procollagen. Nuclease S1 probe protection experiments with mRNA demonstrated that the pro alpha 2(I) chains were shortened because of a deletion of most or all of the 54 nucleotides in exon 6, the exon that contains codons for the cleavage site for procollagen N-proteinase. Sequencing of genomic clones revealed a single-base mutation that converted the first nucleotide of intron 6 from G to A. Therefore, the mutation was a change, in the -GT-consensus splice site, that produced efficient exon skipping. Allele-specific oligonucleotide hybridizations demonstrated that the proband's mother, father, and brother did not have the mutation. Therefore, the mutation was a sporadic one. Analysis of potential 5' splice sites in the 5' end of intron 6 indicated that none had favorable values by the two commonly employed techniques for evaluating such sites. The proband is the fourth reported proband with Ehlers-Danlos syndrome VII with a single-base mutation that causes skipping of exon 6 in the splicing of RNA from either the COL1A1 gene or COL1A2 gene. No other mutations in the two type I procollagen genes have been found in the syndrome. Therefore, such mutations may be a common cause of the phenotype. The primers developed should be useful in screening for the same or similar mutations causing the disease.

Patients of diverse ethnic background were recruited in order to examine whether genetic heterogeneity could be demonstrated in Bloom syndrome (BS). Although most cells from BS patients exhibit high sister-chromatid exchange (SCE), lymphoid cells from some patients exhibit dimorphism for high and low SCE. We addressed the issue of dominance or recessivity of the low-SCE BS phenotype. A high-SCE lymphoblast line, HB1, was mutagenized, and a clone, HB10T, carrying the markers ouabain resistance and thioguanine resistance, was isolated to serve as a fusion parent. Two independent low-SCE BS lines were fused with HB10T, and hybrids were selected in HAT medium supplemented with ouabain. The hybrids, which were tetraploid, exhibited the expected phenotypes when exposed to ouabain and thioguanine. In every case, these hybrids had low SCE levels, establishing dominance of the low-SCE phenotype. The same methodology was also used to assess genetic heterogeneity in BS. A complementation analysis was carried out using high-SCE lymphoblast cell lines derived from BS patients. HB10T was fused with five other high-SCE BS lines. No correction of the high SCE characteristic of BS cells was seen in hybrid lines derived from patients of Ashkenazi Jewish, French-Canadian, Mennonite, or Japanese extraction. Thus, a single gene is responsible for the high-SCE phenotype in BS patients of diverse ethnic origin.

Beckwith-Wiedemann syndrome (BWS), a human overgrowth syndrome with a complex genetic basis, is caused by alterations to chromosome 11p15, a region subject to genomic imprinting. These alterations include translocations, duplications, single gene mutations of p57KIP2, and increased expression of insulin-like growth factor 2 (IGF2). A phenotypically related X-linked overgrowth syndrome, Simpson Golabi Behmel syndrome (SGBS), is caused by alterations in glypican-3 (GPC3), a molecule that may interact with the gene products identified to be important in generating the BWS phenotype, that is, IGF2 and p57KIP2. The crucial defect in these overgrowth syndromes is likely to be an imbalance in contributions of growth-promoting genes versus growth-inhibitory genes in critical tissues at specific developmental stages. Murine models have been used to study the effects of targeted deletions of the genes p57KIP2 and GPC3, as well as overexpression of IGF2. At this time, there are still many issues which remain to be explored before we can fully understand the molecular basis of BWS and SGBS.

Hyper- and hypomethylation at the IGF2-H19 imprinting control region (ICR) result in reciprocal changes in IGF2-H19 expression and the two contrasting growth disorders, Beckwith-Wiedemann syndrome (BWS) and Silver-Russell syndrome (SRS). DNA methylation of the ICR controls the reciprocal imprinting of IGF2 and H19 by preventing the binding of the insulator protein, CTCF. We here show that local changes in histone modifications and CTCF-cohesin binding at the ICR in BWS and SRS together with DNA methylation correlate with the higher order chromatin structure at the locus. In lymphoblastoid cells from control individuals, we found the repressive histone H3K9me3 and H4K20me3 marks associated with the methylated paternal ICR allele and the bivalent H3K4me2/H3K27me3 mark together with H3K9ac and CTCF-cohesin associated with the non-methylated maternal allele. In patient-derived cell lines, the mat/pat asymmetric distribution of these epigenetic marks was lost with H3K9me3 and H4K20me3 becoming biallelic in the BWS and H3K4me2, H3K27me3 and H3K9ac together with CTCF-cohesin becoming biallelic in the SRS. We further show that in BWS and SRS cells, there is opposing chromatin looping conformation mediated by CTCF-cohesin binding sites surrounding the locus. In normal cells, lack of CTCF-cohesin binding at the paternal ICR is associated with monoallelic interaction between two CTCF sites flanking the locus. CTCF-cohesin binding at the maternal ICR blocks this interaction by associating with the CTCF site downstream of the enhancers. The two alternative chromatin conformations are differently favoured in BWS and SRS likely predisposing the locus to the activation of IGF2 or H19, respectively. © The Author 2011. Published by Oxford University Press.

Activating mutations in v-Ha-ras Harvey rat sarcoma viral oncogene homolog (HRAS) have recently been identified as the molecular cause underlying Costello syndrome (CS). To further investigate the phenotypic spectrum associated with germline HRAS mutations and characterize their molecular diversity, subjects with a diagnosis of CS (N = 9), Noonan syndrome (NS; N = 36), cardiofaciocutaneous syndrome (CFCS; N = 4), or with a phenotype suggestive of these conditions but without a definitive diagnosis (N = 12) were screened for the entire coding sequence of the gene. A de novo heterozygous HRAS change was detected in all the subjects diagnosed with CS, while no lesion was observed with any of the other phenotypes. While eight cases shared the recurrent c.34G>A change, a novel c.436G>A transition was observed in one individual. The latter affected residue, p.Ala146, which contributes to guanosine triphosphate (GTP)/guanosine diphosphate (GDP) binding, defining a novel class of activating HRAS lesions that perturb development. Clinical characterization indicated that p.Gly12Ser was associated with a homogeneous phenotype. By analyzing the genomic region flanking the HRAS mutations, we traced the parental origin of lesions in nine informative families and demonstrated that de novo mutations were inherited from the father in all cases. We noted an advanced age at conception in unaffected fathers transmitting the mutation.