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Brain and Behavior Aug 2021Intelligence quotient (IQ) testing is standard for evaluating cognitive abilities in genomic studies but requires professional expertise in administration and...
Intelligence quotient (IQ) testing is standard for evaluating cognitive abilities in genomic studies but requires professional expertise in administration and interpretation, and IQ scores do not translate into insights on implicated brain systems that can link genes to behavior. Individuals with 22q11.2 deletion syndrome (22q11.2DS) often undergo IQ testing to address special needs, but access to testing in resource-limited settings is challenging. The brief Penn Computerized Neurocognitive Battery (CNB) provides measures of cognitive abilities related to brain systems and can screen for cognitive dysfunction. To examine the relation between CNB measures and IQ, we evaluated participants with the 22q11.2DS from Philadelphia and Tel Aviv (N = 117; 52 females; mean age 18.8) who performed both an IQ test and the CNB with a maximum of 5 years between administrations and a subsample (n = 24) who had both IQ and CNB assessments at two time points. We estimated domain-level CNB scores using exploratory factor analysis (including bifactor for overall scores) and related those scores (intraclass correlations (ICCs)) to the IQ scores. We found that the overall CNB accuracy score showed similar correlations between time 1 and time 2 as IQ (0.775 for IQ and 0.721 for CNB accuracy), correlated well with the IQ scores (ICC = 0.565 and 0.593 for time 1 and time 2, respectively), and correlated similarly with adaptive functioning (0.165 and 0.172 for IQ and CNB, respectively). We provide a crosswalk (from linear equating) between standardized CNB and IQ scores. Results suggest that one can substitute the CNB for IQ testing in future genetic studies that aim to probe specific domains of brain-behavior relations beyond IQ.
Topics: Adolescent; Arachnodactyly; DiGeorge Syndrome; Female; Humans; Intelligence; Intelligence Tests; Marfan Syndrome
PubMed: 34213087
DOI: 10.1002/brb3.2221 -
Genetics in Medicine : Official Journal... Jan 2020Congenital contractural arachnodactyly (CCA) is an autosomal dominant connective tissue disorder manifesting joint contractures, arachnodactyly, crumpled ears, and...
PURPOSE
Congenital contractural arachnodactyly (CCA) is an autosomal dominant connective tissue disorder manifesting joint contractures, arachnodactyly, crumpled ears, and kyphoscoliosis as main features. Due to its rarity, rather aspecific clinical presentation, and overlap with other conditions including Marfan syndrome, the diagnosis is challenging, but important for prognosis and clinical management. CCA is caused by pathogenic variants in FBN2, encoding fibrillin-2, but locus heterogeneity has been suggested. We designed a clinical scoring system and diagnostic criteria to support the diagnostic process and guide molecular genetic testing.
METHODS
In this retrospective study, we assessed 167 probands referred for FBN2 analysis and classified them into a FBN2-positive (n = 44) and FBN2-negative group (n = 123) following molecular analysis. We developed a 20-point weighted clinical scoring system based on the prevalence of ten main clinical characteristics of CCA in both groups.
RESULTS
The total score was significantly different between the groups (P < 0.001) and was indicative for classifying patients into unlikely CCA (total score <7) and likely CCA (total score ≥7) groups.
CONCLUSIONS
Our clinical score is helpful for clinical guidance for patients suspected to have CCA, and provides a quantitative tool for phenotyping in research settings.
Topics: Arachnodactyly; Child; Contracture; Diagnosis, Differential; Early Diagnosis; Female; Fibrillin-2; Genetic Testing; Humans; Male; Marfan Syndrome; Phenotype; Retrospective Studies; Sensitivity and Specificity; Sequence Analysis, DNA
PubMed: 31316167
DOI: 10.1038/s41436-019-0609-8 -
Clinical Genetics 2015Cardiovascular abnormalities are the major cause of morbidity and mortality in Marfan syndrome (MFS) and a few clinically related diseases that share, with MFS, the... (Review)
Review
Cardiovascular abnormalities are the major cause of morbidity and mortality in Marfan syndrome (MFS) and a few clinically related diseases that share, with MFS, the pathogenic contribution of dysregulated transforming growth factor β (TGFβ) signaling. They include Loeys-Dietz syndrome, Shprintzen-Goldberg syndrome, aneurysm-osteoarthritis syndrome and syndromic thoracic aortic aneurysms. Unlike the causal association of MFS with mutations in an extracellular matrix protein (ECM), the aforementioned conditions are due to defects in components of the TGFβ pathway. While TGFβ antagonism is being considered as a potential new therapy for these heritable syndromes, several points still need to be clarified in relevant animal models before this strategy could be safely applied to patients. Among others, unresolved issues include whether elevated TGFβ signaling is responsible for all MFS manifestations and is the common trigger of disease in MFS and related conditions. The scope of our review is to highlight the clinical and experimental findings that have forged our understanding of the natural history and molecular pathogenesis of cardiovascular manifestations in this group of syndromic conditions.
Topics: Animals; Aortic Aneurysm, Thoracic; Arachnodactyly; Cardiovascular Abnormalities; Craniosynostoses; Fibrillin-1; Fibrillins; Humans; Loeys-Dietz Syndrome; Marfan Syndrome; Mice; Microfilament Proteins; Signal Transduction; Transforming Growth Factor beta
PubMed: 24867163
DOI: 10.1111/cge.12436 -
European Journal of Medical Genetics Dec 2015This review focusses on impact of a better knowledge of pathogenic mechanisms of Marfan and related disorders on their treatment strategies. It was long believed that a... (Review)
Review
This review focusses on impact of a better knowledge of pathogenic mechanisms of Marfan and related disorders on their treatment strategies. It was long believed that a structural impairment formed the basis of Marfan syndrome as deficiency in the structural extracellular matrix component, fibrillin-1 is the cause of Marfan syndrome. However, the study of Marfan mouse models has revealed the strong involvement of the transforming growth factor-β signalling pathway in the pathogenesis of Marfan. Similarly, this pathway was demonstrated to be key in the pathogenesis of Loeys-Dietz and Shprintzen-Goldberg syndrome. The elucidation of the underlying pathogenic mechanisms has led to new treatment strategies, targeting the overactive TGF-β pathway. Various clinical trials are currently investigating the potential new treatment options. A meta-analysis will contribute to a better understanding of the various trial results.
Topics: Animals; Arachnodactyly; Craniosynostoses; Humans; Loeys-Dietz Syndrome; Marfan Syndrome; Signal Transduction; Transforming Growth Factor beta; Translational Research, Biomedical
PubMed: 26598797
DOI: 10.1016/j.ejmg.2015.10.010 -
Diagnostics (Basel, Switzerland) Sep 2022A long list of syndromic entities can be diagnosed immediately through scrutinizing the clinical phenotype of the craniofacial features. The latter should be assisted...
A long list of syndromic entities can be diagnosed immediately through scrutinizing the clinical phenotype of the craniofacial features. The latter should be assisted via proper radiological interpretations. Different children aged from 1 month to 12 years were referred to our departments seeking orthopedic advice. Primarily, all received variable false diagnoses in other institutes. Two unrelated boys of one month and 12 months were falsely diagnosed as having positional plagiocephaly associated with contractures of idiopathic origin. Two unrelated boys of 14 months and 2 years were diagnosed with pseudo-hydrocephalus and non-specific syndrome, and were referred to explore their skeletal development. Two unrelated girls of 4 years old and 12 years old presented with multiple contractures were referred because of progressive scoliosis. A 4-year-old girl was referred with a false provisional diagnosis of facial diplegia. All children underwent detailed clinical, radiological and tomographic phenotypic characterizations and genetic testing, respectively. Idaho syndrome (craniosynostosis associated with multiple dislocations) was the final diagnosis in the two unrelated boys with plagiocephaly and multiple contractures. Two children falsely diagnosed with pseudo-hydrocephalus and non-specific syndrome, were diagnosed with Silver-Russell syndrome (RSS). Contractural arachnodactyly Beals (CAB) was confirmed as the definitive diagnosis in the two unrelated girls with progressive scoliosis and multiple contractures. Parry-Romberg syndrome (PRS) associated with congenital lumbar kyphosis was the final diagnosis of the girl with the diagnosis of facial diplegia. Hypomethylation of ICR1 was confirmed in the RSS patients. Whole exome sequencing (WES) revealed a heterozygous mutation in the PRS patients. WES and array-CGH showed that no relevant variants or copy number variations (CNV) were identified in the CAB patients. On the one hand, newborn children can manifest diverse forms of abnormal craniofacial features, which are usually associated with either major or minor dysmorphic stigmata. A cleft lip/ palate is a major craniofacial malformation, and frontal bossing or a disproportionate craniofacial contour can be falsely considered as a transient plagiocephaly, which is spontaneously resolved by time. On the other hand, many physicians fall into the problem of deeming a countless number of diseases, such as contractures, as an idiopathic or non-specific syndrome. The latter stems from limited clinical experience. Therefore, failing to establish between the onset of the deformity and other inexplicit abnormal features that the patient or their immediate families or relatives carry is the final outcome. In this study, we used, for the first time, a reconstruction CT scan to further delineate the congenital disruption of the craniofacial anatomy and the other skeletal malformation complex.
PubMed: 36292064
DOI: 10.3390/diagnostics12102375 -
Matrix Biology : Journal of the... Sep 2015The fibrillins, large extracellular matrix molecules, are polymerized to form "microfibrils." The fibrillin microfibril scaffold is populated by microfibril-associated... (Review)
Review
The fibrillins, large extracellular matrix molecules, are polymerized to form "microfibrils." The fibrillin microfibril scaffold is populated by microfibril-associated proteins and by growth factors, which are likely to be latent. The scaffold, associated proteins, and bound growth factors, together with cellular receptors that can sense the microfibril matrix, constitute the fibrillin microenvironment. Activation of TGFβ signaling is associated with the Marfan syndrome, which is caused by mutations in fibrillin-1. Today we know that mutations in fibrillin-1 cause the Marfan syndrome as well as Weill-Marchesani syndrome (and other acromelic dysplasias) and result in opposite clinical phenotypes: tall or short stature; arachnodactyly or brachydactyly; joint hypermobility or stiff joints; hypomuscularity or hypermuscularity. We also know that these different syndromes are associated with different structural abnormalities in the fibrillin microfibril scaffold and perhaps with specific cellular receptors (mechanosensors). How does the microenvironment, framed by the microfibril scaffold and populated by latent growth factors, work? We must await future investigations for the molecular and cellular mechanisms that will answer this question. However, today we can appreciate the importance of the fibrillin microfibril niche as a contextual environment for growth factor signaling and potentially for mechanosensation.
Topics: Animals; Bone Morphogenetic Proteins; Extracellular Matrix; Fibrillin-1; Fibrillins; Humans; Marfan Syndrome; Mechanotransduction, Cellular; Microfibrils; Microfilament Proteins; Transforming Growth Factor beta
PubMed: 25957947
DOI: 10.1016/j.matbio.2015.05.002 -
Genetics in Medicine : Official Journal... Feb 2022Loeys-Dietz syndrome (LDS) is a connective tissue disorder affecting multiple organ systems, including bone.
PURPOSE
Loeys-Dietz syndrome (LDS) is a connective tissue disorder affecting multiple organ systems, including bone.
METHODS
We defined the bone phenotype and clinical predictors of low bone density and fracture risk in 77 patients with LDS type 1 to type 5.
RESULTS
Patients with LDS had dual-energy x-ray absorptiometry (DXA) Z-scores significantly < 0, and 50% of children and 9% of adults had Z-scores < -2. Sixty percent of patients had ≥1 fracture, and 24% of patients with spinal x-rays scans showed spinal compression fractures. Lower body mass index, asthma, male sex and eosinophilic gastrointestinal disease were correlated with lower DXA Z-scores. The count of 5 LDS-associated skeletal features (scoliosis, pes planus, arachnodactyly, spondylolisthesis, and camptodactyly) in patients with LDS was correlated with DXA Z-score. Adults with ≥1 skeletal features had DXA Z-scores significantly < 0, and children with >2 features had DXA Z-score significantly < -2. Bone turnover markers suggest accelerated bone resorption. Data from 5 patients treated with bisphosphonates suggest a beneficial effect.
CONCLUSION
All LDS types are associated with reduced bone density and increased risk of fracture, which may be due to increased bone resorption. Clinical features can predict a subgroup of patients at highest risk of low bone density and fracture risk.
Topics: Absorptiometry, Photon; Bone Density; Bone Diseases, Metabolic; Fractures, Bone; Humans; Loeys-Dietz Syndrome; Male
PubMed: 34906513
DOI: 10.1016/j.gim.2021.10.002 -
Human Genetics Nov 2023CYP26B1 metabolizes retinoic acid in the developing embryo to regulate its levels. A limited number of individuals with pathogenic variants in CYP26B1 have been...
CYP26B1 metabolizes retinoic acid in the developing embryo to regulate its levels. A limited number of individuals with pathogenic variants in CYP26B1 have been documented with a varied phenotypic spectrum, spanning from a severe manifestation involving skull anomalies, craniosynostosis, encephalocele, radio-humeral fusion, oligodactyly, and a narrow thorax, to a milder presentation characterized by craniosynostosis, restricted radio-humeral joint mobility, hearing loss, and intellectual disability. Here, we report two families with CYP26B1-related phenotypes and describe the data obtained from functional studies of the variants. Exome and Sanger sequencing were used for variant identification in family 1 and family 2, respectively. Family 1 reflects a mild phenotype, which includes craniofacial dysmorphism with brachycephaly (without craniosynostosis), arachnodactyly, reduced radioulnar joint movement, conductive hearing loss, learning disability-and compound heterozygous CYP26B1 variants: (p.[(Pro118Leu)];[(Arg234Gln)]) were found. In family 2, a stillborn fetus presented a lethal phenotype with spina bifida occulta, hydrocephalus, poor skeletal mineralization, synostosis, limb defects, and a synonymous homozygous variant in CYP26B1: c.1083C > A. A minigene assay revealed that the synonymous variant created a new splice site, removing part of exon 5 (p.Val361_Asp382del). Enzymatic activity was assessed using a luciferase assay, demonstrating a notable reduction in exogenous retinoic acid metabolism for the variant p.Val361_Asp382del. (~ 3.5 × decrease compared to wild-type); comparatively, the variants p.(Pro118Leu) and p.(Arg234Gln) demonstrated a partial loss of metabolism (1.7× and 2.3× reduction, respectively). A proximity-dependent biotin identification assay reaffirmed previously reported ER-resident protein interactions. Additional work into these interactions is critical to determine if CYP26B1 is involved with other biological events on the ER. Immunofluorescence assay suggests that mutant CYP26B1 is still localized in the endoplasmic reticulum. These results indicate that novel pathogenic variants in CYP26B1 result in varying levels of enzymatic activity that impact retinoic acid metabolism and relate to the distinct phenotypes observed.
Topics: Humans; Retinoic Acid 4-Hydroxylase; Tretinoin; Homozygote; Exons; Craniosynostoses
PubMed: 37755482
DOI: 10.1007/s00439-023-02598-2 -
Frontiers in Genetics 2022Congenital contractural arachnodactyly (CCA) is a rare autosomal dominant disorder of connective tissue characterized by crumpled ears, arachnodactyly, camptodactyly,...
Congenital contractural arachnodactyly (CCA) is a rare autosomal dominant disorder of connective tissue characterized by crumpled ears, arachnodactyly, camptodactyly, large joint contracture, and kyphoscoliosis. The nature course of CCA has not been well-described. We aim to decipher the genetic and phenotypic spectrum of CCA. The cohort was enrolled in Beijing Jishuitan Hospital and Peking Union Medical College Hospital, Beijing, China, based on Deciphering disorders Involving Scoliosis and COmorbidities (DISCO) study (http://www.discostudy.org/). Exome sequencing was performed on patients' blood DNA. A recent published CCA scoring system was validated in our cohort. Seven novel variants and three previously reported variants were identified through exome sequencing. Two variants outside of the neonatal region of gene were found. The phenotypes were comparable between patients in our cohort and previous literature, with arachnodactyly, camptodactyly and large joints contractures found in almost all patients. All patients eligible for analysis were successfully classified into likely CCA based on the CCA scoring system. Furthermore, we found a double disease-causing heterozygous variant of and in a patient with blended phenotypes consisting of CCA and KBG syndrome. The identification of seven novel variants broadens the mutational and phenotypic spectrum of CCA and may provide implications for genetic counseling and clinical management.
PubMed: 35360850
DOI: 10.3389/fgene.2022.804202 -
The Journal of Allergy and Clinical... 2019
Topics: Arachnodactyly; Autoimmunity; Biomarkers; Chromosomes; DiGeorge Syndrome; Humans
PubMed: 31495434
DOI: 10.1016/j.jaip.2019.04.051