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1.
Nature ; 588(7837): 227-231, 2020 12.
Article in English | MEDLINE | ID: mdl-33299190

ABSTRACT

The halo of the Milky Way provides a laboratory to study the properties of the shocked hot gas that is predicted by models of galaxy formation. There is observational evidence of energy injection into the halo from past activity in the nucleus of the Milky Way1-4; however, the origin of this energy (star formation or supermassive-black-hole activity) is uncertain, and the causal connection between nuclear structures and large-scale features has not been established unequivocally. Here we report soft-X-ray-emitting bubbles that extend approximately 14 kiloparsecs above and below the Galactic centre and include a structure in the southern sky analogous to the North Polar Spur. The sharp boundaries of these bubbles trace collisionless and non-radiative shocks, and corroborate the idea that the bubbles are not a remnant of a local supernova5 but part of a vast Galaxy-scale structure closely related to features seen in γ-rays6. Large energy injections from the Galactic centre7 are the most likely cause of both the γ-ray and X-ray bubbles. The latter have an estimated energy of around 1056 erg, which is sufficient to perturb the structure, energy content and chemical enrichment of the circumgalactic medium of the Milky Way.

2.
Clin Genet ; 93(3): 703-706, 2018 03.
Article in English | MEDLINE | ID: mdl-29095483

ABSTRACT

We report on a girl, born to first cousin Lebanese parents, with intellectual disability, seizures, repeated gingivorrhagia, enlarged lower and upper jaws, overgrowth of the gums, high arched and narrow palate, crowded teeth, hirsutism of the back, large abdomen and a small umbilical hernia. Cysts of the mandible, fibrous dysplasia of bones, and enlarged adenoids causing around 60% narrowing of the nasopharyngeal airways were noted at radiographic examination. Her brother presented with the same features in addition to a short stature, an ostium secundum, and more pronounced intellectual disability. He died at the age of 8 years from a severe pulmonary infection and repeated bleeding episodes. A clinical diagnosis of Ramon syndrome was made. Whole exome sequencing studies performed on the family revealed the presence of a novel homozygous missense mutation in ELMO2 gene, p.I606S in the affected individuals. Loss of function mutations in ELMO2 have been recently described in another clinically distinct condition: primary intraosseous vascular malformation or intraosseous hemangioma, called VMOS. Review of the literature and differential diagnoses are discussed.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Cherubism/diagnosis , Cherubism/genetics , Cytoskeletal Proteins/genetics , Epilepsy/diagnosis , Epilepsy/genetics , Fibromatosis, Gingival/diagnosis , Fibromatosis, Gingival/genetics , Growth Disorders/diagnosis , Growth Disorders/genetics , Homozygote , Hypertrichosis/diagnosis , Hypertrichosis/genetics , Intellectual Disability/diagnosis , Intellectual Disability/genetics , Mutation , Child, Preschool , Consanguinity , Echocardiography , Female , Genetic Association Studies , Genetic Testing , Genomics/methods , Humans , Phenotype , Radiography
3.
Lupus ; 27(1): 124-133, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28662595

ABSTRACT

We aimed to identify risk factors for persistently reduced health-related quality of life in childhood-onset lupus and describe a risk profile for persistently reduced health-related quality of life. At a tertiary rheumatology clinic, 50 childhood onset lupus patients were assessed twice, approximately six months apart. Measures of disease activity and patient-reported measures of health-related quality of life, pain, depressive symptoms, anxiety and disability were collected at each visit. At visits 1 and 2, respectively, clinically relevant fatigue was present in 66% and 56% of patients; clinically significant depressive symptoms in 26% and 24%; and clinically significant anxiety in 34% and 28%. Poorer health-related quality of life at follow-up was significantly predicted by higher fatigue and depressive symptoms at the initial visit. Using clinically relevant cut-offs for fatigue and depressive symptoms, patients were assigned to Low ( n = 27) or High Risk ( n = 23) groups. A profile of significantly greater pain, anxiety and coping difficulties was seen in the High Risk group. Routine assessment of fatigue and mood symptoms in youth with childhood-onset lupus could be helpful in identifying those at risk for persistently poor health-related quality of life. Integration of behavioral interventions to address fatigue and mood symptoms into medical care for such patients may be beneficial, but more research in this area is needed.


Subject(s)
Lupus Erythematosus, Systemic/psychology , Adolescent , Age of Onset , Child , Cross-Sectional Studies , Depression/etiology , Fatigue/etiology , Female , Humans , Lupus Erythematosus, Systemic/complications , Pain/etiology , Patient Reported Outcome Measures , Quality of Life , Risk Assessment , Young Adult
4.
Lupus ; 27(4): 657-664, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29301473

ABSTRACT

Introduction Hypertension (HTN) is prevalent in patients with systemic lupus erythematosus (SLE) and causes early cardiovascular aging and progression of renal and cardiac disease. The aim of this longitudinal retrospective study was to evaluate the prevalence of HTN, the follow-up blood pressure trends, and risk factors for HTN in a population-based cohort with childhood-onset SLE (cSLE). Methods Demographic and clinical data of consecutive visits from the baseline to the last visit were extracted from electronic medical records of patients with cSLE. Results A total of 110 patients with cSLE were identified with a median follow-up duration of 29.5 months; 19% had lupus nephritis (LN) at diagnosis. Further, 29% and 23% had HTN and preHTN at the baseline visit. Compared to those without HTN, patients with HTN had higher disease activity, obesity, more frequent LN, and lower eGFR. In multivariate analysis, the presence of LN, obesity, and high extra-renal disease activity were independent predictors of HTN at baseline. Conclusions While HTN is a known feature of LN, HTN is common and persistent in cSLE without LN, with about one-third of patients having uncontrolled elevated blood pressure almost three years after the onset of lupus. In addition to LN, obesity and high overall disease activity were independent predictors of HTN.


Subject(s)
Blood Pressure , Hypertension/epidemiology , Lupus Erythematosus, Systemic/epidemiology , Lupus Nephritis/epidemiology , Adolescent , Age of Onset , Antihypertensive Agents/therapeutic use , Blood Pressure/drug effects , Chi-Square Distribution , Child , Comorbidity , Electronic Health Records , Female , Glomerular Filtration Rate , Humans , Hypertension/diagnosis , Hypertension/drug therapy , Hypertension/physiopathology , Kidney/physiopathology , Kidney Diseases/physiopathology , Logistic Models , Longitudinal Studies , Lupus Erythematosus, Systemic/diagnosis , Lupus Nephritis/diagnosis , Male , Multivariate Analysis , Obesity/epidemiology , Ohio/epidemiology , Prevalence , Retrospective Studies , Risk Factors , Time Factors
5.
Lupus ; 26(11): 1205-1211, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28478696

ABSTRACT

The gold standard for the classification of lupus nephritis is renal histology but reporting variation exists. The aim of this study was to assess the inter-observer variability of the 2003 International Society of Nephrology/Royal Pathology Society (ISN/RPS) lupus nephritis histological classification criteria in children. Histopathologists from a reference centre and three tertiary paediatric centres independently reviewed digitalized renal histology slides from 55 children with lupus nephritis. Histological ISN/RPS Class was assigned and features scored; lupus nephritis-activity [scored 0-24], lupus nephritis-chronicity [0-12] and tubulointerstitial activity [0-21]. In the cohort (73% females), the age at the time of biopsy was 15.5 ± 0.39 (mean ± standard error) years. Based on the reference centre, 42% (23/55) had ISN/RPS Class IV with lupus nephritis-activity score 4.23 ± 0.50, lupus nephritis-chronicity 1.81 ± 0.18 and tubulointerstitial activity 4.45 ± 0.35. There were 4-54 (mean 16.7) glomeruli per biopsy. Pathologists had fair agreement for ISN/RPS assignment (kappa; 0.26 ± 0.12), lupus nephritis-chronicity (intra-class correlation 0.36 ± 0.09) and tubulointerstitial activity (0.22 ± 0.09) scores. There was good agreement for lupus nephritis-activity scores (intra-class correlation 0.69 ± 0.06). When categorized into proliferative and non-proliferative disease, poor agreement among sites remained (kappa 0.24 ± 0.11). Despite unified criteria for the interpretation of histological features of lupus nephritis, marked reporting variation remains in clinical practice. As proliferative lupus nephritis is managed more intensively, this may influence renal outcomes.


Subject(s)
Kidney Glomerulus/pathology , Lupus Nephritis/pathology , Pathologists , Adolescent , Biopsy , Female , Humans , Lupus Nephritis/classification , Male , Observer Variation , Predictive Value of Tests , Prognosis , Reproducibility of Results , Severity of Illness Index , United Kingdom , United States
6.
Lupus ; 26(9): 927-936, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28361601

ABSTRACT

Objectives The renal activity index for lupus (RAIL) score was developed in children with lupus nephritis as a weighted sum of six urine biomarkers (UBMs) (neutrophil gelatinase-associated lipocalin, monocyte chemotactic protein 1, ceruloplasmin, adiponectin, hemopexin and kidney injury molecule 1) measured in a random urine sample. We aimed at prospectively validating the RAIL in adults with lupus nephritis. Methods Urine from 79 adults was collected at the time of kidney biopsy to assay the RAIL UBMs. Using receiver operating characteristic curve analysis, we evaluated the accuracy of the RAIL to discriminate high lupus nephritis activity status (National Institutes of Health activity index (NIH-AI) score >10), from low/moderate lupus nephritis activity status (NIH-AI score ≤10). Results In this mixed racial cohort, high lupus nephritis activity was present in 15 patients (19%), and 71% had proliferative lupus nephritis. Use of the identical RAIL algorithm developed in children resulted in only fair prediction of lupus nephritis activity status of adults (area under the receiver operating characteristic curve (AUC) 0.62). Alternative weightings of the six RAIL UBMs as suggested by logistic regression yielded excellent accuracy to predict lupus nephritis activity status (AUC 0.88). Accuracy of the model did not improve with adjustment of the UBMs for urine creatinine or albumin, and was little influenced by concurrent kidney damage. Conclusions The RAIL UBMs provide excellent prediction of lupus nephritis activity in adults. Age adaption of the RAIL is warranted to optimize its discriminative validity to predict high lupus nephritis activity status non-invasively.


Subject(s)
Biomarkers/urine , Kidney/pathology , Lupus Nephritis/pathology , Lupus Nephritis/urine , Adiponectin/metabolism , Adiponectin/urine , Adult , Ceruloplasmin/metabolism , Ceruloplasmin/urine , Chemokine CCL2/metabolism , Cross-Sectional Studies , Female , Hemopexin/metabolism , Hemopexin/urine , Hepatitis A Virus Cellular Receptor 1/metabolism , Humans , Kidney/immunology , Kidney Function Tests/methods , Lipocalin-2/metabolism , Lupus Nephritis/immunology , Male , Predictive Value of Tests , Prospective Studies , Severity of Illness Index
7.
Lupus ; 25(8): 857-63, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27252262

ABSTRACT

In this review we critically analyze pulmonary, gastrointestinal and cardiac manifestations of childhood-onset systemic lupus erythematosus (cSLE). Clinical manifestations of these organ systems may be the initial manifestation of cSLE; frequently occur with very active cSLE; and are potential life-threatening manifestations often presenting to the emergency department and requiring admission to the intensive care unit. Early recognition and treatment of the pulmonary, gastrointestinal and cardiac manifestations of cSLE will result in improved prognosis and better outcomes.


Subject(s)
Cardiovascular Diseases/physiopathology , Gastrointestinal Diseases/physiopathology , Lung Diseases/physiopathology , Lupus Erythematosus, Systemic/complications , Age of Onset , Child , Humans , Prognosis
8.
Lupus ; 25(9): 1012-8, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26873651

ABSTRACT

OBJECTIVE: To evaluate candidate biomarkers to predict future renal function decline (RFD) in children and adults with lupus nephritis (LN). METHODS: At the time of enrollment into prospective observational LN cohort studies liver-type fatty acid binding protein (LFABP), albumin, monocyte chemoattractant protein-1 (MCP-1), uromodulin, transferrin, and hepcidin were measured in urine samples of two cohorts of patients with LN, one followed at a pediatric (cohort-1; n = 28) and one at an adult institution (cohort-2; n = 69). The primary outcome was RFD, defined in cohort-1 as a decrease in estimated glomerular filtration rate (eGFR) of ≥20% and in cohort-2 as a sustained increase of ≥25% in serum creatinine concentration (SCr), both from baseline. RESULTS: All patients (n = 97) had normal eGFR or SCr at the time of urine collection at baseline. RFD occurred in 29% (8/28) of patients in cohort-1 during a mean follow-up of 6.1 months, and in 30% (21/69) of those in cohort-2 during a mean follow-up of 60 months. Individually, in cohort-1, levels of MCP-1, transferrin, LFABP, and albumin were higher in the RFD group than those who maintained renal function, with statistical significance for LFABP and albumin. In cohort-2 the RFD group also had higher levels of urine MCP-1 and albumin than others. The combination of LFABP, MCP-1, albumin, and transferrin had good predictive accuracy for RFD in both cohorts (area under the ROC curve = 0.77-0.82). CONCLUSION: The combinatorial urine biomarker LFABP, MCP-1, albumin, and transferrin shows promise as a predictor of renal functional decline in LN, and warrants further investigation.


Subject(s)
Lupus Nephritis/physiopathology , Lupus Nephritis/urine , Adolescent , Adult , Biomarkers/urine , Chemokine CCL2/urine , Child , Creatinine/urine , Female , Glomerular Filtration Rate , Hepcidins/urine , Humans , Kidney Function Tests , Lupus Nephritis/diagnosis , Male , Middle Aged , Prospective Studies , Transferrin/urine , Uromodulin/urine , Young Adult
9.
Clin Genet ; 87(1): 34-41, 2015.
Article in English | MEDLINE | ID: mdl-24716670

ABSTRACT

Robinow Syndrome (RS), a rare skeletal dysplasia syndrome, is characterized by dysmorphic features resembling a fetal face, mesomelic limb shortening, hypoplastic external genitalia in males, and renal and vertebral anomalies. Both autosomal dominant and autosomal recessive patterns of inheritance have been reported. Since the description of autosomal dominant Robinow Syndrome (ADRS; OMIM 180700) in 1969 by Meinhard Robinow and colleagues, the molecular etiology remained elusive until only recently. WNT5A was proposed to be the candidate gene for ADRS, as mutations were found in two affected families, one of those being the originally described index family. We report three families with RS caused by novel heterozygous WNT5A mutations, which were confirmed in the first family by whole exome sequencing, and in all by Sanger sequencing. To our knowledge, this is the largest number of published families with ADRS in whom a WNT5A mutation was identified. Families 1 and 2 are the first cases showing de novo inheritance in the affected family members and thus strengthen the evidence for WNT5A as the causative gene in ADRS. Finally, we propose WNT5A mutation specificity in ADRS, which may affect interactions with other proteins in the Wnt pathway.


Subject(s)
Craniofacial Abnormalities/genetics , Craniofacial Abnormalities/pathology , Dwarfism/genetics , Dwarfism/pathology , Limb Deformities, Congenital/genetics , Limb Deformities, Congenital/pathology , Models, Molecular , Phenotype , Proto-Oncogene Proteins/genetics , Urogenital Abnormalities/genetics , Urogenital Abnormalities/pathology , Wnt Proteins/genetics , Base Sequence , Exome/genetics , Gene Frequency , Genotype , Humans , Male , Molecular Sequence Data , Pedigree , Proto-Oncogene Proteins/chemistry , Sequence Analysis, DNA , Wnt Proteins/chemistry , Wnt-5a Protein
10.
Lupus ; 24(10): 1081-6, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25701565

ABSTRACT

OBJECTIVES: The objective of this report is to use diffusion-tensor imaging (DTI) for investigating white-matter connectivity changes associated with neurocognitive dysfunction in childhood-onset lupus (cSLE-NCD) as measured by formal neuropsychological testing. METHODS: DTI was performed in six individuals with (cSLE-NCD) and nine without neurocognitive dysfunction (cSLE-noNCD) as well as 14 healthy controls. Presence of neurocognitive deficits was identified by formal neuropsychological testing. The brain was divided into 116 regions, and pairwise connectivity (defined as the number of streamlines with an endpoint in each of those regions) and streamline density (defined as the number of streamlines passing through a region regardless of endpoints) were evaluated. Group comparisons were made for regional and global measures of streamline density and pairwise connectivity. RESULTS: A significant decrease in global streamline density was observed in the cSLE-NCD vs. control group (1189 vs. 1305 p = 0.002) and vs. cSLE-noNCD (1189 vs 1320 p = 0.001). The cSLE-noNCD and control groups had similar streamline density. A similar pattern for pairwise connectivity was observed with a significant decrease in the cSLE-NCD group (217) versus the cSLE-noNCD (236; p = 0.013) and control group (238; p = 0.004). Regional measures of pairwise connectivity displayed mixed results. CONCLUSIONS: The analysis of DTI in this pilot study shows cSLE-NCD is associated with global loss of streamline density and pairwise connectivity, suggesting breakdown of the structural network. These results complement previously reported functional and volumetric findings that suggest cSLE-NCD is associated with measurable changes in gray and white matter. If confirmed in larger cohorts, DTI abnormalities could be used as imaging biomarkers of cSLE-NCD.


Subject(s)
Diffusion Tensor Imaging/methods , Lupus Vasculitis, Central Nervous System/diagnostic imaging , Lupus Vasculitis, Central Nervous System/diagnosis , Neurocognitive Disorders/diagnostic imaging , Neurocognitive Disorders/physiopathology , Adolescent , Biomarkers , Case-Control Studies , Child , Cross-Sectional Studies , Demography , Diffusion Tensor Imaging/trends , Female , Humans , Lupus Vasculitis, Central Nervous System/pathology , Magnetic Resonance Imaging , Male , Neurocognitive Disorders/pathology , Neuroimaging/methods , Neuropsychological Tests , Pilot Projects , Psychometrics/methods , Radiography , Socioeconomic Factors
11.
Lupus ; 24(2): 191-7, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25335488

ABSTRACT

OBJECTIVE: This study evaluated the effects of obesity on health-related quality of life (HRQOL) measures in juvenile-onset systemic lupus erythematosus (jSLE). METHODS: Obesity was defined as a body mass index (BMI) ≥ 95 th percentile according to the Sex-specific Center for Disease Control BMI-For-Age Charts and determined in a multicenter cohort of jSLE patients. In this secondary analysis, the domain and summary scores of the Pediatric Quality of Life (PedsQL) Inventory and the Child Health Questionnaire (CHQ) of obese jSLE patients were compared to those of non-obese jSLE patients as well as historical obese and non-obese healthy controls. Mixed-effects modeling was performed to evaluate the relationship between obesity and HRQOL measures. RESULTS: Among the 202 jSLE patients, 25% (n = 51) were obese. Obesity had a significant negative impact on HRQOL in jSLE, even after adjusting for differences in current corticosteroid use, disease activity, disease damage, gender and race between groups. Obese jSLE patients had lower physical functioning compared to non-obese jSLE patients, and to non-obese and obese healthy controls. Compared to their non-obese counterparts, obese jSLE patients also had worse school functioning, more pain, worse social functioning and emotional functioning. Parents of obese jSLE patients worry more. The CHQ scores for obese jSLE patients were also worse compared to non-obese jSLE patients in several other domains. CONCLUSION: Our study demonstrates the detrimental effects of obesity on patient-reported outcomes in jSLE. This supports the importance of weight management for the therapeutic plan of jSLE.


Subject(s)
Lupus Erythematosus, Systemic/physiopathology , Obesity/complications , Quality of Life , Adolescent , Body Mass Index , Case-Control Studies , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Male , Surveys and Questionnaires , Young Adult
13.
Mol Microbiol ; 87(1): 132-51, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23136884

ABSTRACT

Analysing culture supernatants of yeast and hyphal cells of Candida albicans, we found two close homologues of pathogenesis-related (PR-) 1 proteins, Rbe1p and Rbt4p, in the secretome. Due to sequence homology, three additional, yet not characterized open reading frames, ORF19.6200, ORF19.2787 and ORF19.2336, together with RBE1 and RBT4 were assigned to a novel family of CaPRY proteins. In a Δrbe1/Δrbt4 deletion strain, genome-wide transcriptional analysis revealed differential transcription of only a limited set of genes implicated in virulence and oxidative stress response. Single deletion of RBE1 or RBT4 in a clinical C. albicans isolate resulted in a moderate but significant attenuation in virulence in a mouse model for disseminated candidiasis. However, a synergistic effect was observed in a Δrbe1/Δrbt4 double deletion strain, where virulence was strongly affected. Remarkably, transcription of RBT4 and RBE1 was each upregulated in blastospores of Δrbe1 or hyphae of Δrbt4 deletion strains respectively, indicating functional complementation thereby compensating a potential virulence defect in the single deletion strains. Furthermore, the double deletion strain showed increased sensitivity to attack by polymorphonuclear leucocytes. Therefore, the crucial contribution of both C. albicans pathogenesis-related proteins to virulence might be vested in protection against phagocyte attack.


Subject(s)
Candida albicans/genetics , Candida albicans/pathogenicity , Fungal Proteins/genetics , Fungal Proteins/metabolism , Amino Acid Sequence , Animals , Candida albicans/metabolism , DNA, Fungal/genetics , Gene Expression Profiling , Gene Expression Regulation, Fungal , Genome, Fungal , Mice , Molecular Sequence Data , Open Reading Frames , Oxidative Stress/genetics , Phenotype , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Sequence Alignment , Sequence Deletion , Virulence/genetics
14.
Arthritis Rheum ; 64(1): 285-96, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22031171

ABSTRACT

OBJECTIVE: Statins reduce atherosclerosis and cardiovascular morbidity in the general population, but their efficacy and safety in children and adolescents with systemic lupus erythematosus (SLE) are unknown. This study was undertaken to determine the 3-year efficacy and safety of atorvastatin in preventing subclinical atherosclerosis progression in pediatric-onset SLE. METHODS: A total of 221 participants with pediatric SLE (ages 10-21 years) from 21 North American sites were enrolled in the Atherosclerosis Prevention in Pediatric Lupus Erythematosus study, a randomized double-blind, placebo-controlled clinical trial, between August 2003 and November 2006 with 36-month followup. Participants were randomized to receive atorvastatin (n=113) or placebo (n=108) at 10 or 20 mg/day depending on weight, in addition to usual care. The primary end point was progression of mean-mean common carotid intima-media thickening (CIMT) measured by ultrasound. Secondary end points included other segment/wall-specific CIMT measures, lipid profile, high-sensitivity C-reactive protein (hsCRP) level, and SLE disease activity and damage outcomes. RESULTS: Progression of mean-mean common CIMT did not differ significantly between treatment groups (0.0010 mm/year for atorvastatin versus 0.0024 mm/year for placebo; P=0.24). The atorvastatin group achieved lower hsCRP (P=0.04), total cholesterol (P<0.001), and low-density lipoprotein (P<0.001) levels compared with placebo. In the placebo group, CIMT progressed significantly across all CIMT outcomes (0.0023-0.0144 mm/year; P<0.05). Serious adverse events and critical safety measures did not differ between groups. CONCLUSION: Our results indicate that routine statin use over 3 years has no significant effect on subclinical atherosclerosis progression in young SLE patients; however, further analyses may suggest subgroups that would benefit from targeted statin therapy. Atorvastatin was well tolerated without safety concerns.


Subject(s)
Anticholesteremic Agents/therapeutic use , Atherosclerosis/prevention & control , Heptanoic Acids/therapeutic use , Lupus Erythematosus, Systemic/drug therapy , Pyrroles/therapeutic use , Adolescent , Atherosclerosis/complications , Atherosclerosis/diagnosis , Atorvastatin , Carotid Intima-Media Thickness , Child , Disease Progression , Double-Blind Method , Female , Humans , Lipids/blood , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/complications , Male , Treatment Outcome , Young Adult
15.
Nat Genet ; 29(4): 465-8, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11704759

ABSTRACT

Noonan syndrome (MIM 163950) is an autosomal dominant disorder characterized by dysmorphic facial features, proportionate short stature and heart disease (most commonly pulmonic stenosis and hypertrophic cardiomyopathy). Webbed neck, chest deformity, cryptorchidism, mental retardation and bleeding diatheses also are frequently associated with this disease. This syndrome is relatively common, with an estimated incidence of 1 in 1,000-2,500 live births. It has been mapped to a 5-cM region (NS1) [corrected] on chromosome 12q24.1, and genetic heterogeneity has also been documented. Here we show that missense mutations in PTPN11 (MIM 176876)-a gene encoding the nonreceptor protein tyrosine phosphatase SHP-2, which contains two Src homology 2 (SH2) domains-cause Noonan syndrome and account for more than 50% of the cases that we examined. All PTPN11 missense mutations cluster in interacting portions of the amino N-SH2 domain and the phosphotyrosine phosphatase domains, which are involved in switching the protein between its inactive and active conformations. An energetics-based structural analysis of two N-SH2 mutants indicates that in these mutants there may be a significant shift of the equilibrium favoring the active conformation. This implies that they are gain-of-function changes and that the pathogenesis of Noonan syndrome arises from excessive SHP-2 activity.


Subject(s)
Mutation, Missense , Noonan Syndrome/genetics , Protein Tyrosine Phosphatases/genetics , Chromosomes, Human, Pair 12 , Genetic Heterogeneity , Humans , Intracellular Signaling Peptides and Proteins , Models, Molecular , Molecular Sequence Data , Noonan Syndrome/enzymology , Protein Conformation , Protein Tyrosine Phosphatase, Non-Receptor Type 11 , Protein Tyrosine Phosphatase, Non-Receptor Type 6 , Protein Tyrosine Phosphatases/chemistry
16.
Nat Genet ; 25(4): 423-6, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10932187

ABSTRACT

Robinow syndrome is a short-limbed dwarfism characterized by abnormal morphogenesis of the face and external genitalia, and vertebral segmentation. The recessive form of Robinow syndrome (RRS; OMIM 268310), particularly frequent in Turkey, has a high incidence of abnormalities of the vertebral column such as hemivertebrae and rib fusions, which is not seen in the dominant form. Some patients have cardiac malformations or facial clefting. We have mapped a gene for RRS to 9q21-q23 in 11 families. Haplotype sharing was observed between three families from Turkey, which localized the gene to a 4. 9-cM interval. The gene ROR2, which encodes an orphan membrane-bound tyrosine kinase, maps to this region. Heterozygous (presumed gain of function) mutations in ROR2 were previously shown to cause dominant brachydactyly type B (BDB; ref. 7). In contrast, Ror2-/- mice have a short-limbed phenotype that is more reminiscent of the mesomelic shortening observed in RRS. We detected several homozygous ROR2 mutations in our cohort of RRS patients that are located upstream from those previously found in BDB. The ROR2 mutations present in RRS result in premature stop codons and predict nonfunctional proteins.


Subject(s)
Abnormalities, Multiple/genetics , Receptors, Cell Surface/genetics , Abnormalities, Multiple/pathology , Amino Acid Sequence , Amino Acid Substitution , Base Sequence , Chromosome Mapping , Chromosomes, Human, Pair 9/genetics , DNA/chemistry , DNA/genetics , DNA Mutational Analysis , Face/abnormalities , Family Health , Female , Genes, Recessive , Genotype , Humans , Limb Deformities, Congenital/genetics , Male , Microsatellite Repeats , Molecular Sequence Data , Mutation , Pedigree , Receptor Protein-Tyrosine Kinases/genetics , Receptor Tyrosine Kinase-like Orphan Receptors , Sequence Deletion , Sequence Homology, Amino Acid , Syndactyly , Syndrome
17.
Nat Genet ; 21(3): 302-4, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10080184

ABSTRACT

The secreted polypeptide noggin (encoded by the Nog gene) binds and inactivates members of the transforming growth factor beta superfamily of signalling proteins (TGFbeta-FMs), such as BMP4 (ref. 1). By diffusing through extracellular matrices more efficiently than TGFbeta-FMs, noggin may have a principal role in creating morphogenic gradients. During mouse embryogenesis, Nog is expressed at multiple sites, including developing bones. Nog-/- mice die at birth from multiple defects that include bony fusion of the appendicular skeleton. We have identified five dominant human NOG mutations in unrelated families segregating proximal symphalangism (SYM1; OMIM 185800) and a de novo mutation in a patient with unaffected parents. We also found a dominant NOG mutation in a family segregating multiple synostoses syndrome (SYNS1; OMIM 186500); both SYM1 and SYNS1 have multiple joint fusion as their principal feature. All seven NOG mutations alter evolutionarily conserved amino acid residues. The findings reported here confirm that NOG is essential for joint formation and suggest that NOG requirements during skeletogenesis differ between species and between specific skeletal elements within species.


Subject(s)
Abnormalities, Multiple/genetics , Joints/abnormalities , Mutation , Proteins/genetics , Synostosis/genetics , Adolescent , Animals , Carrier Proteins , Cats , Chickens , Chromosome Mapping , Female , Finger Joint/abnormalities , Gene Expression Regulation, Developmental , Genetic Markers , Gorilla gorilla , Heterozygote , Humans , Joints/physiology , Male , Mice , Molecular Sequence Data , Morphogenesis , Sequence Analysis , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid , Swine , Xenopus laevis , Zebrafish
18.
Nat Genet ; 23(2): 217-21, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10508521

ABSTRACT

Retinitis pigmentosa (RP) comprises a clinically and genetically heterogeneous group of diseases that afflicts approximately 1.5 million people worldwide. Affected individuals suffer from a progressive degeneration of the photoreceptors, eventually resulting in severe visual impairment. To isolate candidate genes for chorioretinal diseases, we cloned cDNAs specifically or preferentially expressed in the human retina and the retinal pigment epithelium (RPE) through a novel suppression subtractive hybridization (SSH) method. One of these cDNAs (RET3C11) mapped to chromosome 1q31-q32.1, a region harbouring a gene involved in a severe form of autosomal recessive RP characterized by a typical preservation of the para-arteriolar RPE (RP12; ref. 3). The full-length cDNA encodes an extracellular protein with 19 EGF-like domains, 3 laminin A G-like domains and a C-type lectin domain. This protein is homologous to the Drosophila melanogaster protein crumbs (CRB), and denoted CRB1 (crumbs homologue 1). In ten unrelated RP patients with preserved para-arteriolar RPE, we identified a homozygous AluY insertion disrupting the ORF, five homozygous missense mutations and four compound heterozygous mutations in CRB1. The similarity to CRB suggests a role for CRB1 in cell-cell interaction and possibly in the maintenance of cell polarity in the retina. The distinct RPE abnormalities observed in RP12 patients suggest that CRB1 mutations trigger a novel mechanism of photoreceptor degeneration.


Subject(s)
Drosophila Proteins , Eye Proteins/genetics , Membrane Proteins/genetics , Retinitis Pigmentosa/genetics , Alu Elements/genetics , Amino Acid Sequence , Amino Acid Substitution , Animals , Base Sequence , Blotting, Northern , Cell Line , Chromosome Mapping , Chromosomes, Human, Pair 1/genetics , DNA Mutational Analysis , DNA, Complementary/chemistry , DNA, Complementary/genetics , Drosophila melanogaster/genetics , Family Health , Female , Gene Expression Regulation, Developmental , Homozygote , Humans , Male , Molecular Sequence Data , Mutagenesis, Insertional , Mutation , Pedigree , Point Mutation , Polymorphism, Single-Stranded Conformational , RNA, Messenger/genetics , RNA, Messenger/metabolism , Retinitis Pigmentosa/pathology , Sequence Analysis, DNA , Tissue Distribution
19.
Nat Genet ; 23(4): 413-9, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10581026

ABSTRACT

We report that mutation of COL11A2 causes deafness previously mapped to the DFNA13 locus on chromosome 6p. We found two families (one American and one Dutch) with autosomal dominant, non-syndromic hearing loss to have mutations in COL11A2 that are predicted to affect the triple-helix domain of the collagen protein. In both families, deafness is non-progressive and predominantly affects middle frequencies. Mice with a targeted disruption of Col11a2 also were shown to have hearing loss. Electron microscopy of the tectorial membrane of these mice revealed loss of organization of the collagen fibrils. Our findings revealed a unique ultrastructural malformation of inner-ear architecture associated with non-syndromic hearing loss, and suggest that tectorial membrane abnormalities may be one aetiology of sensorineural hearing loss primarily affecting the mid-frequencies.


Subject(s)
Collagen/genetics , Hearing Loss, Sensorineural/genetics , Mutation, Missense , Amino Acid Sequence , Animals , Base Sequence , Chromosomes, Human, Pair 6/genetics , DNA/genetics , Disease Models, Animal , Female , Genes, Dominant , Hearing Loss, Sensorineural/pathology , Hearing Loss, Sensorineural/physiopathology , Humans , In Situ Hybridization , Male , Mice , Mice, Knockout , Molecular Sequence Data , Pedigree , Polymorphism, Single-Stranded Conformational
20.
Clin Genet ; 80(1): 31-8, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21204793

ABSTRACT

The Kleefstra syndrome (Online Mendelian Inheritance in Man 607001) is caused by a submicroscopic 9q34.3 deletion or by intragenic euchromatin histone methyl transferase 1 (EHMT1) mutations. So far only de novo occurrence of mutations has been reported, whereas 9q34.3 deletions can be either de novo or caused by complex chromosomal rearrangements or translocations. Here we give the first descriptions of affected parent-to-child transmission of Kleefstra syndrome caused by small interstitial deletions, approximately 200 kb, involving part of the EHMT1 gene. Additional genome-wide array studies in the parents showed the presence of similar deletions in both mothers who only had mild learning difficulties and minor facial characteristics suggesting either variable clinical expression or somatic mosaicism for these deletions. Further studies showed only one of the maternal deletions resulted in significantly quantitative differences in signal intensity on the array between the mother and her child. But by investigating different tissues with additional fluorescent in situ hybridization (FISH) and multiplex ligation-dependent probe amplification (MLPA) analyses, we confirmed somatic mosaicism in both mothers. Careful clinical and cytogenetic assessments of parents of an affected proband with an (interstitial) 9q34.3 microdeletion are merited for accurate estimation of recurrence risk.


Subject(s)
Abnormalities, Multiple/genetics , Chromosomes, Human, Pair 9/genetics , Histone-Lysine N-Methyltransferase/genetics , Language Development Disorders/genetics , Mosaicism , Muscle Hypotonia/genetics , Sequence Deletion , Child , Child, Preschool , Female , Humans , Infant , Male , Oligonucleotide Array Sequence Analysis , Syndrome , Telomere/genetics
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