[Show abstract][Hide abstract] ABSTRACT: Maternal Uniparental Disomy of chromosome 14 (matUPD(14)) resembles Prader-Willi syndrome. Since positive effects of growth hormone (GH) are observed in individuals with PWS, treatment with GH may be useful in individuals with matUPD(14) as well. The aim of this study was to investigate the effect of GH treatment on growth and body composition in children with matUPD(14).
Prospective observational study of GH treatment in two girls with matUPD(14) during 2 years, and spontaneous growth in another matUPD(14) girl of similar age.
Three girls (patient A, B and C, aged 8.9, 11.4 and 12.7 years respectively) with matUPD(14).
Patients A and B were treated with GH during two years. Patient C was not treated with GH, as she was diagnosed at an age at which she attained near-final height. Main outcome measures included height, weight, body proportions, IGF-1, bone age, DXA scan for body composition.
In both treated girls a considerable increase in height (from -2.3SD and -1.2SD to -1.2SD and -0.6SD, respectively) and IGF-1 levels (from +0.1SD and -1.4SD to +1.3SD and +0.9SD, respectively), and in patient A a decrease in weight (+1.2 SD to -0.7SD), and improved body composition (fat percentage from 51.5% to 45.4%). Both experienced improved muscle strength.
GH treatment in matUPD(14) cases can show beneficial effects on growth and body composition if started in time. Larger, international studies to determine detailed effectivity and side-effects are suggested. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Many current paediatric studies concern relationships between genes and environment and discuss aetiology, treatment and prevention of Mendelian and multifactorial diseases. Many of these studies depend on collection and long-term storage of data and biological material from affected children in biobanks. Stored material is a source of personal information of the donor and his family and could be used in an undesirable context, potentially leading to discrimination and interfering with a child's right to an open future. Here, we address the normative framework regarding biobanking with residual tissue of children, protecting the privacy interests of young biobank donors (0-12 years). We analyse relevant legal documents concerning storage and use of children's material for research purposes. We explore the views of 17 Dutch experts involved in paediatric biobank research and focus on informed consent for donation of leftover tissue as well as disclosure of individual research findings resulting from biobank research. The results of this analysis show that experts have no clear consensus about the appropriate rules for storage of and research with children's material in biobanks. Development of a framework that provides a fair balance between fundamental paediatric research and privacy protection is necessary.European Journal of Human Genetics advance online publication, 15 April 2015; doi:10.1038/ejhg.2015.59.
European journal of human genetics: EJHG 04/2015; DOI:10.1038/ejhg.2015.59 · 4.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Cornelia de Lange syndrome (CdLS) is characterized by facial dysmorphism, growth failure, intellectual disability, limb malformations and multiple organ involvement. Mutations in five genes, encoding subunits of the cohesin complex (SMC1A, SMC3, RAD21) and its regulators (NIPBL, HDAC8), account for at least 70% of patients with CdLS or CdLS-like phenotypes. To date, only the clinical features from a single CdLS patient with SMC3 mutation has been published. Here, we report the efforts of an international research and clinical collaboration to provide clinical comparison of sixteen patients with CdLS-like features caused by mutations in SMC3. Modelling of the mutation effects on protein structure suggests a dominant-negative effect on the multimeric cohesin complex. When compared to typical CdLS, many SMC3-associated phenotypes are also characterized by postnatal microcephaly but with a less distinctive craniofacial appearance, a milder prenatal growth retardation that worsens in childhood, few congenital heart defects and an absence of limb deficiencies. While most mutations are unique, two unrelated affected individuals shared the same mutation but presented with different phenotypes. This work confirms that de novo SMC3 mutations account for ∼1-2% of CdLS-like phenotypes. This article is protected by copyright. All rights reserved.
Human Mutation 02/2015; DOI:10.1002/humu.22761 · 5.05 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Implementation of next-generation DNA sequencing (NGS) technology into routine diagnostic genome care requires strategic choices. Instead of theoretical discussions on the consequences of such choices, we compared NGS-based diagnostic practices in eight clinical genetic centers in the Netherlands, based on genetic testing of nine pre-selected patients with cardiomyopathy. We highlight critical implementation choices, including the specific contributions of laboratory and medical specialists, bioinformaticians and researchers to diagnostic genome care, and how these affect interpretation and reporting of variants. Reported pathogenic mutations were consistent for all but one patient. Of the two centers that were inconsistent in their diagnosis, one reported to have found 'no causal variant', thereby underdiagnosing this patient. The other provided an alternative diagnosis, identifying another variant as causal than the other centers. Ethical and legal analysis showed that informed consent procedures in all centers were generally adequate for diagnostic NGS applications that target a limited set of genes, but not for exome- and genome-based diagnosis. We propose changes to further improve and align these procedures, taking into account the blurring boundary between diagnostics and research, and specific counseling options for exome- and genome-based diagnostics. We conclude that alternative diagnoses may infer a certain level of 'greediness' to come to a positive diagnosis in interpreting sequencing results. Moreover, there is an increasing interdependence of clinic, diagnostics and research departments for comprehensive diagnostic genome care. Therefore, we invite clinical geneticists, physicians, researchers, bioinformatics experts and patients to reconsider their role and position in future diagnostic genome care.
European Journal of HumanGenetics 01/2015; 23(9). DOI:10.1038/ejhg.2014.279 · 4.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Type 2 collagen disorders encompass a diverse group of skeletal dysplasias that are commonly associated with orthopedic, ocular, and hearing problems. However, the frequency of many clinical features has never been determined. We retrospectively investigated the clinical, radiological, and genotypic data in a group of 93 patients with molecularly confirmed SEDC or a related disorder. The majority of the patients (80/93) had short stature, with radiological features of SEDC (n = 64), others having SEMD (n = 5), Kniest dysplasia (n = 7), spondyloperipheral dysplasia (n = 2), or Torrance-like dysplasia (n = 2). The remaining 13 patients had normal stature with mild SED, Stickler-like syndrome or multiple epiphyseal dysplasia. Over 50% of the patients had undergone orthopedic surgery, usually for scoliosis, femoral osteotomy or hip replacement. Odontoid hypoplasia was present in 56% (95% CI 38-74) and a correlation between odontoid hypoplasia and short stature was observed. Atlanto-axial instability, was observed in 5 of the 18 patients (28%, 95% CI 10-54) in whom flexion-extension films of the cervical spine were available; however, it was rarely accompanied by myelopathy. Myopia was found in 45% (95% CI 35-56), and retinal detachment had occurred in 12% (95% CI 6-21; median age 14 years; youngest age 3.5 years). Thirty-two patients complained of hearing loss (37%, 95% CI 27-48) of whom 17 required hearing aids. The ophthalmological features and possibly also hearing loss are often relatively frequent and severe in patients with splicing mutations. Based on clinical findings, age at onset and genotype-phenotype correlations in this cohort, we propose guidelines for the management and follow-up in this group of disorders.
American Journal of Medical Genetics Part A 01/2015; 167(3). DOI:10.1002/ajmg.a.36922 · 2.05 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The European Journal of Human Genetics is the official Journal of the European Society of Human Genetics, publishing high-quality, original research papers, short reports, News and Commentary articles and reviews in the rapidly expanding field of human genetics and genomics.
European journal of human genetics: EJHG 12/2014; DOI:10.1038/ejhg.2014.270 · 4.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Dihydropyrimidine dehydrogenase (DPD) deficiency is an autosomal recessive disorder of the pyrimidine metabolism. Deficiency of this enzyme leads to an accumulation of thymine and uracil and a deficiency of metabolites distal to the catabolic enzyme. The disorder presents with a wide clinical spectrum, ranging from asymptomatic to severe neurological manifestations, including intellectual disability, seizures, microcephaly, autistic behavior, and eye abnormalities. Here, we report on an 11-year-old Malaysian girl and her 6-year-old brother with DPD deficiency who presented with intellectual disability, microcephaly, and hypotonia. Brain MRI scans showed generalized cerebral and cerebellar atrophy and callosal body dysgenesis in the boy. Urine analysis showed strongly elevated levels of uracil in the girl and boy (571 and 578 mmol/mol creatinine, respectively) and thymine (425 and 427 mmol/mol creatinine, respectively). Sequence analysis of the DPYD gene showed that both siblings were homozygous for the mutation c.1651G>A (pAla551Thr).
[Show abstract][Hide abstract] ABSTRACT: Robin Sequence (RS) is characterized by micrognathia and upper airway obstruction (UAO), with or without cleft palate, causing respiratory and feeding problems. Management options are: positioning; nasopharyngeal airway (NPA); tongue-lip adhesion (TLA); mandibular distraction (MDO); and tracheostomy. Controversy exists in literature regarding RS definition and management. Here we describe definitions, management strategies and criteria in opting for management strategies, used by Dutch and Belgian cleft teams.
Journal of Cranio-Maxillofacial Surgery 11/2014; 43(1). DOI:10.1016/j.jcms.2014.10.015 · 2.60 Impact Factor