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We described how family trauma experienced by Native Americans/Alaskan Indians (NA/AIs) influenced substance use. We explored participants’ desire for culturally tailored interventions during subst...

GPC3 and GPC4 are the only two genes in which mutations are known to cause Simpson-Golabi-Behmel syndrome type 1 (SGBS1). The majority of SGBS1 patients have point mutations or deletions in GPC3. Only one SGBS1 family has been reported with duplication of both GPC3 and GPC4. Although clinical presentation of SGBS1 in affected males is well defined, the phenotype in female carriers is less clear. In total, six female carriers with clinical expression of SGBS1 have been reported to date. In this study, we provide description of two families with rare duplications in both GPC3 and GPC4. These imbalances resulted in SGBS1 in males, while female carriers with skewed X-inactivation exhibited significant features of SGBS1 including congenital heart defect, hernias, intellectual disability and coarse facial features. In family 2, a SGBS diagnosis was not considered in the father until after the diagnosis had been first considered and made in the affected daughter. We emphasize on the importance of testing at risk females and careful examination of those who are found to be carriers of SGBS1. We also discuss and provide supportive evidence for the role of skewed X-inactivation in clinical expression of SGBS1 in female carriers.

Summary Congenital heart defects are a feature of several genetic haploinsufficiency syndromes, often involving transcriptional regulators. One property of haploinsufficient genes is their propensity for network interactions at the gene or protein level. In this article we took advantage of an online dataset of high throughput screening of mutations that are embryonic lethal in mice. Our aim was to identify new genes where the loss of function caused cardiovascular phenotypes resembling the 22q11.2 deletion syndrome models, that is, heterozygous and homozygous loss of Tbx1. One gene with a potentially haploinsufficient phenotype was identified, Setd5, thought to be involved in chromatin modification. We found murine Setd5 haploinsufficiency to be associated with double outlet right ventricle and perimembranous ventricular septal defect, although no genetic interaction with Tbx1 was detected. Conditional mutagenesis revealed that Setd5 was required in cardiopharyngeal mesoderm for progression of the heart tube through the ballooning stage to create a four‐chambered heart.

Context Although primary adrenal insufficiency (PAI) in children and young people is often due to congenital adrenal hyperplasia (CAH) or autoimmunity, other genetic causes occur. The relative prevalence of these conditions is poorly understood. Objective We investigated genetic causes of PAI in children and young people over a 25 year period. Design, Setting and Participants Unpublished and published data were reviewed for 155 young people in the United Kingdom who underwent genetic analysis for PAI of unknown etiology in three major research centers between 1993 and 2018. We pre-excluded those with CAH, autoimmune, or metabolic causes. We obtained additional data from NR0B1 (DAX-1) clinical testing centers. Intervention and Outcome Measurements Genetic analysis involved a candidate gene approach (1993 onward) or next generation sequencing (NGS; targeted panels, exomes) (2013-2018). Results A genetic diagnosis was reached in 103/155 (66.5%) individuals. In 5 children the adrenal insufficiency resolved and no genetic cause was found. Pathogenic variants occurred in 11 genes: MC2R (adrenocorticotropin receptor; 30/155, 19.4%), NR0B1 (DAX-1; 7.7%), CYP11A1 (7.7%), AAAS (7.1%), NNT (6.5%), MRAP (4.5%), TXNRD2 (4.5%), STAR (3.9%), SAMD9 (3.2%), CDKN1C (1.3%), and NR5A1/steroidogenic factor-1 (SF-1; 0.6%). Additionally, 51 boys had NR0B1 variants identified through clinical testing. Although age at presentation, treatment, ancestral background, and birthweight can provide diagnostic clues, genetic testing was often needed to define the cause. Conclusions PAI in children and young people often has a genetic basis. Establishing the specific etiology can influence management of this lifelong condition. NGS approaches improve the diagnostic yield when many potential candidate genes are involved.

Cornelia de Lange syndrome (CdLS) is a multisystem genetic disorder associated with unusual facial features, limb abnormalities, a wide range of health conditions, and intellectual disability. Mutations in five genes that encode (SMC1A, SMC3, RAD21) or regulate (NIPBL, HDAC8) the cohesin complex have been identified in up to 70% of individuals. Genetic cause remains unknown for a proportion of individuals. There is substantial heterogeneity in all aspects of CdLS but very little is known about what predicts phenotypic heterogeneity. In this study, we evaluated genotype-phenotype associations in 34 individuals with CdLS. Participants with NIPBL mutations had significantly lower self help skills and were less likely to have verbal skills relative to those who were negative for the NIPBL mutation. No significant differences were identified between the groups in relation to repetitive behavior, mood, interest and pleasure, challenging behavior, activity, impulsivity, and characteristics of autism spectrum disorder whilst controlling differences in self help skills. Significant correlations indicating lower mood, interest and pleasure, and increased insistence on sameness with older age were identified for those who were NIPBL mutation positive. The findings suggest similarities in the behavioral phenotype between those with and without the NIPBL mutation once differences in self help skills are controlled for. However, there may be subtle differences in the developmental trajectory of these behaviors according to genetic mutation status in CdLS.

Hematopoietic cell transplantation (HCT) conditioned using myeloablative conditioning (MAC) is complicated by end organ injury due to endothelial dysfunction and graft versus host disease. Mucositis and oxidant injury results in micronutrient deficiency. Ascorbic acid (AA) levels were measured in 15 patients undergoing HCT conditioned with MAC (11 allogeneic and four autologous HCT). Ascorbate levels declined postconditioning to 27.3 μMol/L (±14.1) by day 0 (P = .03 compared with pretransplant baseline), reaching a nadir level of 21.5 (±13.8) on day 14 (P = .003) post-transplant. Patients undergoing allogeneic HCT continued to have low AA levels to day 60 post-transplant. The role of AA in maintaining endothelial function and hematopoietic as well as T-cell recovery is provided, developing the rationale for repletion of vitamin C following HCT.

Hematopoietic cell transplantation (HCT) conditioned using myeloablative conditioning (MAC) is complicated by end organ injury due to endothelial dysfunction and graft versus host disease. Mucositis and oxidant injury results in micronutrient deficiency. Ascorbic acid (AA) levels were measured in 15 patients undergoing HCT conditioned with MAC (11 allogeneic and 4 autologous HCT). Ascorbate levels declined post conditioning to 27.3 (±14.1) by day 0 (p

Fraser syndrome (OMIM 219000) is a multisystem malformation usually comprising cryptophthalmos, syndactyly and renal defects(1). Here we report autozygosity mapping and show that the locus FS1 at chromosome 4q21 is associated with Fraser syndrome, although the condition is genetically heterogeneous. Mutation analysis identified five frameshift mutations in FRAS1, which encodes one member of a family of novel proteins related to an extracellular matrix (ECM) blastocoelar protein found in sea urchin. The FRAS1 protein contains a series of N-terminal cysteine-rich repeat motifs previously implicated in BMP metabolism, suggesting that it has a role in both structure and signal propagation in the ECM. It has been speculated that Fraser syndrome is a human equivalent of the blebbed phenotype in the mouse(2), which has been associated with mutations in at least five loci including bl(3). As mapping data were consistent with homology of FRAS1 and bl, we screened DNA from bl/bl mice and identified a premature termination of mouse Fras1. Thus, the bl mouse is a model for Fraser syndrome in humans, a disorder caused by disrupted epithelial integrity in utero.

Objectives To assess diagnostic agreement for occupational asthma, and to identify case and rater characteristics associated with this diagnosis. Methods Summaries of possible occupational asthma cases were sent to 104 occupational and respiratory physicians. Raters assigned likelihood scores (0–100%) of occupational asthma based on case histories (phase 1), and on histories plus investigative procedures (phase 2). Interclass correlation coefficients were calculated as statistical measures of reliability for occupational asthma scores. Comparisons between mean scores were assessed for statistical significance using tests based on multilevel models. RRs were calculated to summarise effects of raters9 demographics, and of supplying investigative procedures information. Results Occupational asthma scores showed limited agreement within each group of (occupational or respiratory) physicians, but scores were not systematically different. The difference between mean overall scores was 2.1% (52.1% occupational physicians; 50.0% respiratory physicians) in phase 1 (95% CI −2.6 to 6.8, p=0.37). In phase 2, mean overall scores were 46.1% (occupational physicians) and 41.5% (respiratory physicians); the difference in mean overall scores was 4.6% (95% CI −3.5 to 12.5, p=0.27). Raters with General Medical Council registration ≥1986 were more likely to give a positive occupational asthma diagnosis. In phase 2, male raters were more likely to label cases as occupational asthma than female raters (RR 4.5, 95% CI 3.3 to 6.0). Conclusions The RR of a positive occupational asthma diagnosis was unaffected by clinical speciality. Further work on why physicians consider cases to be occupational asthma will assist better diagnosis and prevention of this disease.

‘General languor and debility, feebleness of the heart's action, irritability of the stomach, and a peculiar change of the colour of the skin’ – forms part of the original description of Addison's disease, primary hypoadrenalism.1 The condition represents a diagnostic challenge for the clinician, a non-specific pattern of presentation notoriously difficult to identify, that follows a potentially fatal course. Data on the occurrence of spontaneous bilateral adrenal haemorrhage is sparse though it is becoming increasingly recognized. The case and corresponding literature are discussed to highlight the risk factors and clinical presentation of the condition.

The Guidelines in Emergency Medicine Network (GEMNet) has been created to promote best medical practice in a range of conditions presenting to emergency departments (EDs) in the UK. This guideline presents a summary of the best available evidence to guide the use of thromboprophylaxis in adult ambulatory outpatients who present to the ED following acute limb trauma and require temporary immobilisation. The document has been developed following discussion among emergency physicians and collegiate fellows to decide which topics would benefit from the development of clinical guidelines. The document is intended as a guideline for use in the ED by emergency physicians and is based on the review of the best existing evidence for treatments used in this setting. The document is summarised as a Clinical Decision Support Guideline that has been presented as an easy to follow algorithm. The intention is for each guideline to be updated and reviewed as further evidence becomes available. The formal revision date has been set at 5 years from publication, though the guideline is subject to continuous informal review.

Aortic arch artery patterning defects account for approximately 20% of congenital cardiovascular malformations and are observed frequently in velocardiofacial syndrome (VCFS). In the current study, we screened for chromosome rearrangements in patients suspected of VCFS, but who lacked a 22q11 deletion or TBX1 mutation. One individual displayed hemizygous CHD7, which encodes a chromodomain protein. CHD7 haploinsufficiency is the major cause of coloboma, heart defect, atresia choanae, retarded growth and development, genital hypoplasia, and ear anomalies/deafness (CHARGE) syndrome, but this patient lacked the major diagnostic features of coloboma and choanal atresia. Because a subset of CHARGE cases also display 22q11 deletions, we explored the embryological relationship between CHARGE and VCSF using mouse models. The hallmark of Tbx1 haploinsufficiency is hypo/aplasia of the fourth pharyngeal arch artery (PAA) at E10.5. Identical malformations were observed in Chd7 heterozygotes, with resulting aortic arch interruption at later stages. Other than Tbx1, Chd7 is the only gene reported to affect fourth PAA development by haploinsufficiency. Moreover, Tbx1+/–;Chd7+/– double heterozygotes demonstrated a synergistic interaction during fourth PAA, thymus, and ear morphogenesis. We could not rescue PAA morphogenesis by restoring neural crest Chd7 expression. Rather, biallelic expression of Chd7 and Tbx1 in the pharyngeal ectoderm was required for normal PAA development.

Cyp26a1, a gene required for retinoic acid (RA) inactivation during embryogenesis, was previously identified as a potential Tbx1 target from a microarray screen comparing wild-type and null Tbx1 mouse embryo pharyngeal arches (pa) at E9.5. Using real-time PCR and in situ hybridization analysis of Cyp26a1 and its two functionally related family members Cyp26b1 and c1, we demonstrate reduced and/or altered expression for all three genes in pharyngeal tissues of Tbx1 null embryos. Blockade of Cyp26 function in the chick embryo using R115866, a specific inhibitor of Cyp26 enzyme function, resulted in a dose-dependent phenocopy of the Tbx1 null mouse including loss of caudal pa and pharyngeal arch arteries (paa), small otic vesicles, loss of head mesenchyme and, at later stages, DiGeorge Syndrome-like heart defects, including common arterial trunk and perimembranous ventricular septal defects. Molecular markers revealed a serious disruption of pharyngeal pouch endoderm (ppe) morphogenesis and reduced staining for smooth muscle cells in paa. Expression of the RA synthesizing enzyme Raldh2 was also up-regulated and altered Hoxb1 expression indicated that RA levels are raised in R115866-treated embryos as reported for Tbx1 null mice. Down-regulation of Tbx1 itself was observed, in accordance with previous observations that RA represses Tbx1 expression. Thus, by specifically blocking the action of the Cyp26 enzymes we can recapitulate many elements of the Tbx1 mutant mouse, supporting the hypothesis that the dysregulation of RA-controlled morphogenesis contributes to the Tbx1 loss of function phenotype.

22q11-deletion (DiGeorge/velocardiofacial) syndrome (22q11DS) is modeled by mutation of murine transcription factor Tbx1. As part of efforts to identify transcriptional targets of Tbx1, we analyzed the transcriptome of the pharyngeal region of Df1/+;Tbx1+/− embryos at 9.5 days of embryonic development using two independent microarray platforms. In this model, embryos are null for Tbx1, with hemizygosity of genes in cis with Tbx1 on one chromosome providing a positive control for array sensitivity. Reduced mRNA levels of genes deleted from Df1 were detected on both platforms. Expression level filtering and statistical analysis identified several genes that were consistently differentially expressed between mutant and wild type embryos. Real-time quantitative PCR and in situ hybridization validated diminished expression of Pax9 and Gcm2, genes known to be required for normal thymus and parathyroid gland morphogenesis, whereas Pax1, Hoxa3, Eya1, and Foxn1, which are similarly required, were not down-regulated. Gbx2, a gene required for normal arch artery development, was down-regulated specifically in the pharyngeal endoderm and the posterior part of pharyngeal arch 1, and is a potential point of cross talk between the Tbx1 and Fgf8 controlled pathways. These experiments highlight which genes and pathways potentially affected by lack of Tbx1, and whose role may be explored further by testing for epistasis using mouse mutants.

Hemizygosity for a region of human Chromosome (Chr) 22q11 has been associated with a wide range of congenital malformation syndromes. The major abnormalities encountered are cardiac defects, dysmorphic facies, T cell dysfunction, clefting, hypocalcemia, and learning or behavioral problems (Wilson et al. 1993). Individually, patients may be diagnosed as DiGeorge syndrome (DGS), velo-cardio-facial syndrome (VCFS), conotruncal anomaly face (CTAF), Cayler syndrome, or Opitz GBBB syndrome. The deletions detected in these conditions are large, encompassing 2 Mb or more of 22q11. Comparisons of terminal and submicroscopic interstitial deletions have been made in order to establish a shortest region of deletion overlap for these disorders. A minimal DiGeorge critical region has recently been proposed (MDGCR, Budarf et al. 1995). A family segregating a 2;22 balanced translocation has been described (Augusseau et al. 1986). The proband, ADU, has DiGeorge syndrome, and his mother, although very mildly affected, has VCFS. Two other family members have the translocation, but there is very little clinical information available, other than they are not severely affected by either condition. The translocation breakpoint (ADUBP) maps within the MDGCR, implying that the translocation disrupts a gene haploinsufficient in DiGeorge syndrome. DGCR2 was isolated during attempts to isolate genes at or adjacent to the ADU breakpoint. The DGCR2 gene encodes a transmembrane protein (Demczuk et al. 1995). The alternative name of IDD was an acronym for Integral membrane protein, Deleted in DiGeorge syndrome (Wadey et al. 1995). The putative extracellular region contains domains with similarity to both the LDL-receptor binding domain and C-type lectins, suggesting a ligand-binding function for this part of the molecule. It has been suggested that this might involve mediation of the interaction of cephalic and cardiac neural crest cells with the substratum or with other cells during their migration. A defective neural crest cell contribution can mimic the DGS in some experimental systems (Kirby et al. 1983). However, no point mutations of DGCR2 have been detected despite extensive searches (Wadey et al. 1995, and unpublished data). Recent data have suggested that the ADUBP exerts a position effect on the gene or genes haploinsufficient in DGS, rather than directly disrupting a protein-encoding locus (Levy et al. 1995; Sutherland et al. 1996). Thus, as the closest structural gene to the ADU breakpoint, DGCR2 remains of interest despite the lack of mutations. To investigate the gene further, we have cloned and mapped the murine homolog of DGCR2. A 10.5 dpc (days post coitum) mouse embryo cDNA library was screened with the human DGCR2 clone, and three positives were obtained. The clone with the largest insert, KT4, was subcloned into M13 and sequenced. An open reading frame of 548 amino acids was detected, and the GCG program bestfit revealed that this ORF was 92% identical to the human DGCR2 sequence, with three gaps (Fig. 1a). The accession number for Dgcr2 is X95480. Database searches were repeated with BLAST and Maspar in order that similarity to recent submissions might be detected. A highly significant match was obtained with GB:D78641 over the entire length of the gene (Fig. 1a), including identity within the 38 UTR (not shown). This gene, Sez-12, is described as encoding a membrane glycoprotein and was isolated from a murine neuronal precursor cDNA library (Kajiwara et al. 1996). Sez-12 is over 99% identical to Dgcr2 at the amino acid level, although there are two gaps in the alignment (Fig. 1a). Differences between the Sez-12 and Dgcr2 sequences were checked and confirmed. The main difference is a gap of three amino acids at Dgcr2 residue 109, in the LDL binding domain of Sez-12. The human and murine Dgcr2 sequences are identical at this point, as are sequences from additional mouse clones, indicating that the sequence presented here is most likely to be correct. No other informative database matches were obtained. Partial sequence of a chick Dgcr2 cDNA was also obtained providing information concerning the aminoterminal 92 amino acids of Cdgcr2 (accession number X95885). This region contains the signal peptide and the LDL-receptor binding domain. This chick sequence was 75% identical and 83% similar to the murine Dgcr2 in this region, with two gaps. A schematic of the Dgcr2 gene showing the position of the conserved motifs is given in Fig. 1b. Northern analysis of mRNA from 10.5 to 15.5 dpc embryos detected a single transcript of 4.4kb (not shown), as demonstrated for the human gene and the Sez-12 transcripts. Comparison with the level of expression of b-actin suggests no great change in the expression of Dgcr2 takes place during this period. Expression of Dgcr2 was studied further by wholemount hybridization of 9.5 dpc embryos, in an initial attempt to identify whether Dgcr2 might be expressed in regions containing neural crest cells and their derivatives. Dgcr2 expression was detected throughout the embryo, but expression was particularly strong in the first and second branchial arches, and in the limb buds (Fig. 2). At 9.5–10 dpc, sections through wholemount embryos detected expression of Dgcr2 in the dorsal half of the mid and hindbrain, and the optic lobes (Fig. 2iii). Dorsal mesenchyme surrounding the neuroepithelium was also positive, particularly around the hindbrain. High levels of expression were found throughout the branchial arches (Fig. 2iv). There Correspondence to: P.J. Scambler

Deletions within human chromosome 22q11 cause a wide variety of birth defects including the DiGeorge syndrome and velo-cardio-facial (Shprintzen) syndrome. Despite the positional cloning of several genes from the critical region, it is still not possible to state whether the phenotype is secondary to haploinsufficiency of one or more than one gene. In embryological studies phenocopies of these abnormalities are produced by a variety of actions which disrupt the contribution made by the cranial and cardiac neural crest to development. The TUPLE1/HIRA gene is related to WD40 domain transcriptional regulators and maps within the DiGeorge critical region. We have cloned the chick homologue of HIRA and conducted in situ expression analysis in early chick embryos. Hira is expressed in the developing neural plate, the neural tube, neural crest and the mesenchyme of the head and branchial arch structures. HIRA may therefore have a role in the haploinsufficiency syndromes caused by deletion of 22q11.