Publications by authors named "Anthony Vandersteen"

While next generation sequencing has expanded the scientific understanding of Inborn Errors of Immunity (IEI), the clinical use and re-use of exome sequencing is still emerging. We revisited clinical exome data from 1300 IEI patients using an updated in silico IEI gene panel. Variants were classified and curated through expert review.

View Article and Find Full Text PDF

Background: Generating rigorous evidence to inform care for rare diseases requires reliable, sustainable, and longitudinal measurement of priority outcomes. Having developed a core outcome set for pediatric medium-chain acyl-CoA dehydrogenase (MCAD) deficiency, we aimed to assess the feasibility of prospective measurement of these core outcomes during routine metabolic clinic visits.

Methods: We used existing cohort data abstracted from charts of 124 children diagnosed with MCAD deficiency who participated in a Canadian study which collected data from birth to a maximum of 11 years of age to investigate the frequency of clinic visits and quality of metabolic chart data for selected outcomes.

View Article and Find Full Text PDF
Article Synopsis
  • Ehlers-Danlos syndromes (EDS) are genetic disorders that affect connective tissue, and there are 13 different types of EDS.
  • Researchers studied 174 EDS patients who didn't have a clear genetic diagnosis to find out more about their conditions using advanced genetic testing called whole exome sequencing (WES).
  • They discovered several genetic variants related to EDS and other similar disorders, showing that more research and better testing can help identify difficult cases and improve diagnosis.
View Article and Find Full Text PDF

The vast majority of reported (likely) pathogenic missense variants in the genes coding for the fibrillar collagens leads to the substitution of one of the obligatory glycine residues in the Gly-Xaa-Yaa repeat sequence of the triple helical domain. Their phenotypic consequences and deleterious effects have been well-documented. However, with increasing access to molecular diagnostic testing based on next-generation sequencing techniques, such as sequencing of multi-gene panels and whole-exome sequencing, non-glycine substitutions are more frequently identified in individuals suspected to have a heritable collagen disorder, but their pathogenic effect is often difficult to predict.

View Article and Find Full Text PDF

Our understanding of inflammatory bowel disease is changing as we identify genetic variants associated with immune dysregulation. Inflammatory bowel disease undetermined, even when diagnosed in older children and adolescents, in the setting of multiple inflammatory and infectious diseases should raise the suspicion of complex immune dysregulation with a monogenic basis. We report a case of inflammatory bowel disease undetermined triggered by exposure to a nonsteroidal antiinflammatory drug in a 16-year-old girl with a background history of juvenile idiopathic arthritis, cytopenias, recurrent respiratory tract and middle ear infections, and esophageal candidiasis.

View Article and Find Full Text PDF
Article Synopsis
  • The study aimed to determine if new genetic variants contribute to moyamoya disease (MMD) in children without affected relatives by sequencing exomes of 28 children with MMD and their unaffected parents.
  • Researchers found three novel rare genetic variants linked to aggressive forms of MMD, often presenting early in childhood, along with other vascular issues like renal artery stenosis.
  • The findings suggest a new syndrome characterized by rare genetic mutations that disrupt crucial amino acids, leading to severe MMD symptoms before the age of three and affecting multiple arteries.
View Article and Find Full Text PDF

Purpose: Currently, 31 patients with classical-like EDS (clEDS) due to tenascin-X deficiency have been reported in the literature. We report on the clinical and molecular characteristics of 20 additional patients with clEDS to expand knowledge and to enable improved management of this rare genetic disorder.

Methods: Patients diagnosed with clEDS by the national EDS service in the UK (n = 21) and abroad (n = 1) were asked for consent for publication of their clinical and molecular data.

View Article and Find Full Text PDF

Background: The Ehlers-Danlos syndromes (EDS) are a group of connective tissue disorders with several recognised types. Patients with a type of EDS have connective tissue abnormalities resulting in a varying degree of joint hypermobility, skin and vascular fragility and generalised tissue friability. Classical EDS (cEDS) typically occurs as a result of dominant pathogenic variants in or .

View Article and Find Full Text PDF
Article Synopsis
  • The Canadian Inherited Metabolic Diseases Research Network (CIMDRN) involves 14 treatment centers and aims to enhance health outcomes for children with inherited metabolic diseases (IMD) by developing a clinical data collection platform and managing data quality.
  • The study collects demographic and diagnostic data from children diagnosed with 31 targeted IMDs, focusing on five prioritized diseases for in-depth longitudinal data, while ensuring data accuracy through user-friendly forms and regular reviews.
  • As of June 2019, CIMDRN enrolled 798 participants, achieving a 96% completion rate for minimum data sets, while identifying challenges in data interpretation and organization, but maintaining strong accuracy in disease diagnosis information.
View Article and Find Full Text PDF

Arthrochalasia Ehlers-Danlos syndrome (aEDS) is a rare autosomal dominant connective tissue disorder that is characterized by congenital bilateral hip dislocations, severe generalized joint hypermobility, recurrent joint (sub)luxations, and skin hyperextensibility. To date, 42 patients with aEDS have been published. We report 12 patients with aEDS from 10 families with 6 unpublished individuals and follow-up data on 6 adult patients.

View Article and Find Full Text PDF

Advances in genomics have transformed our ability to identify the genetic causes of rare diseases (RDs), yet we have a limited understanding of the mechanistic roles of most genes in health and disease. When a novel RD gene is first discovered, there is minimal insight into its biological function, the pathogenic mechanisms of disease-causing variants, and how therapy might be approached. To address this gap, the Canadian Rare Diseases Models and Mechanisms (RDMM) Network was established to connect clinicians discovering new disease genes with Canadian scientists able to study equivalent genes and pathways in model organisms (MOs).

View Article and Find Full Text PDF

The 2017 classification of Ehlers-Danlos syndromes (EDS) identifies three types associated with causative variants in COL1A1/COL1A2 and distinct from osteogenesis imperfecta (OI). Previously, patients have been described with variable features of both disorders, and causative variants in COL1A1/COL1A2; but this phenotype has not been included in the current classification. Here, we expand and re-define this OI/EDS overlap as a missing EDS type.

View Article and Find Full Text PDF

Weill-Marchesani syndrome (WMS) is a rare genetic disorder that affects the musculoskeletal system, the eye, and the cardiovascular system. Individuals with WMS present with short stature, joint contractures, thick skin, microspherophakia, small and dislocated lenses, and cardiac valve anomalies. WMS can be caused by recessive mutations in ADAMTS10 (WMS 1), ADAMTS17 (WMS 4), or LTBP2 (WMS 3), or by dominant mutations in fibrillin-1 (FBN1) (WMS 2); all genes encode secreted extracellular matrix (ECM) proteins.

View Article and Find Full Text PDF
Article Synopsis
  • Lamb-Shaffer syndrome (LAMSHF) is a rare neurodevelopmental disorder linked to genetic changes in the SOX5 gene, primarily through microdeletions, affecting brain development and function.
  • The study analyzed data from 41 new patients with different SOX5 alterations to better understand the genetic variations and their impact on clinical symptoms.
  • Findings revealed that while most genetic changes disrupt SOX5's ability to bind DNA, leading to varying degrees of intellectual disability and language delays, the severity of symptoms doesn't strongly correlate with specific genetic alterations.
View Article and Find Full Text PDF

The Ehlers-Danlos syndromes (EDS) are heritable disorders of connective tissue (HDCT) with joint hypermobility, skin hyperextensibility and tissue fragility, which were recently re-classified (2017 International Classification). Most patients (>90%) with Classical Ehlers-Danlos syndrome (cEDS) have a mutation in the COL5A1 or COL5A2 genes encoding type V procollagen. A small number of patients with the p.

View Article and Find Full Text PDF

Purpose: The Ehlers-Danlos syndromes (EDS) are a group of rare inherited connective tissue disorders. Vascular EDS (vEDS) is caused by pathogenic variants in COL3A1, most frequently glycine substitutions. We describe the phenotype of the largest series of vEDS patients with glutamic acid to lysine substitutions (Glu>Lys) in COL3A1, which were all previously considered to be variants of unknown significance.

View Article and Find Full Text PDF

PurposeIn 2012 we reported in six individuals a clinical condition almost indistinguishable from PLOD1-kyphoscoliotic Ehlers-Danlos syndrome (PLOD1-kEDS), caused by biallelic mutations in FKBP14, and characterized by progressive kyphoscoliosis, myopathy, and hearing loss in addition to connective tissue abnormalities such as joint hypermobility and hyperelastic skin. FKBP14 is an ER-resident protein belonging to the family of FK506-binding peptidyl-prolyl cis-trans isomerases (PPIases); it catalyzes the folding of type III collagen and interacts with type III, type VI, and type X collagens. Only nine affected individuals have been reported to date.

View Article and Find Full Text PDF

Schinzel-Giedion syndrome (SGS) is a rare developmental disorder characterized by multiple malformations, severe neurological alterations and increased risk of malignancy. SGS is caused by de novo germline mutations clustering to a 12bp hotspot in exon 4 of SETBP1. Mutations in this hotspot disrupt a degron, a signal for the regulation of protein degradation, and lead to the accumulation of SETBP1 protein.

View Article and Find Full Text PDF
Article Synopsis
  • * Recent advances have revealed new EDS subtypes and genetic mutations, prompting the International EDS Consortium to propose a revised classification that recognizes 13 subtypes along with specific clinical diagnosis criteria.
  • * The revised classification aims to address the genetic and clinical complexity of EDS, emphasizing the importance of genetic testing for most subtypes and improving distinctions between hypermobile EDS and other related disorders.
View Article and Find Full Text PDF

The Ehlers-Danlos syndromes comprise a clinically and genetically heterogeneous group of heritable connective tissue disorders, which are characterized by joint hypermobility, skin hyperextensibility, and tissue friability. In the Villefranche Nosology, six subtypes were recognized: The classical, hypermobile, vascular, kyphoscoliotic, arthrochalasis, and dermatosparaxis subtypes of EDS. Except for the hypermobile subtype, defects had been identified in fibrillar collagens or in collagen-modifying enzymes.

View Article and Find Full Text PDF

Purpose: Ehlers-Danlos syndrome (EDS) comprises a group of overlapping hereditary disorders of connective tissue with significant morbidity and mortality, including major vascular complications. We sought to identify the diagnostic utility of a next-generation sequencing (NGS) panel in a mixed EDS cohort.

Methods: We developed and applied PCR-based NGS assays for targeted, unbiased sequencing of 12 collagen and aortopathy genes to a cohort of 177 unrelated EDS patients.

View Article and Find Full Text PDF

Periodontal Ehlers-Danlos syndrome (pEDS) is an autosomal-dominant disorder characterized by early-onset periodontitis leading to premature loss of teeth, joint hypermobility, and mild skin findings. A locus was mapped to an approximately 5.8 Mb region at 12p13.

View Article and Find Full Text PDF