| 1. |
- Collett-Solberg, Paulo F., et al.
(författare)
-
Diagnosis, Genetics, and Therapy of Short Stature in Children : A Growth Hormone Research Society International Perspective
- 2019
-
Ingår i: Hormone Research in Paediatrics. - : S. Karger. - 1663-2818 .- 1663-2826. ; 92:1, s. 1-14
-
Tidskriftsartikel (refereegranskat)abstract
- The Growth Hormone Research Society (GRS) convened a Workshop in March 2019 to evaluate the diagnosis and therapy of short stature in children. Forty-six international experts participated at the invitation of GRS including clinicians, basic scientists, and representatives from regulatory agencies and the pharmaceutical industry. Following plenary presentations addressing the current diagnosis and therapy of short stature in children, breakout groups discussed questions produced in advance by the planning committee and reconvened to share the group reports. A writing team assembled one document that was subsequently discussed and revised by participants. Participants from regulatory agencies and pharmaceutical companies were not part of the writing process. Short stature is the most common reason for referral to the pediatric endocrinologist. History, physical examination, and auxology remain the most important methods for understanding the reasons for the short stature. While some long-standing topics of controversy continue to generate debate, including in whom, and how, to perform and interpret growth hormone stimulation tests, new research areas are changing the clinical landscape, such as the genetics of short stature, selection of patients for genetic testing, and interpretation of genetic tests in the clinical setting. What dose of growth hormone to start, how to adjust the dose, and how to identify and manage a suboptimal response are still topics to debate. Additional areas that are expected to transform the growth field include the development of long-acting growth hormone preparations and other new therapeutics and diagnostics that may increase adult height or aid in the diagnosis of growth hormone deficiency.
|
|
| 2. |
- Gkourogianni, Alexandra, et al.
(författare)
-
Clinical characterization of patients with autosomal dominant short stature due to aggrecan mutations
- 2017
-
Ingår i: Journal of Clinical Endocrinology and Metabolism. - Cary, USA : Oxford University Press. - 0021-972X .- 1945-7197. ; 102:2, s. 460-469
-
Tidskriftsartikel (refereegranskat)abstract
- Context: Heterozygous mutations in the Aggrecan gene (ACAN) cause autosomal dominant short stature with bone age (BA) acceleration, premature growth cessation and minor skeletal abnormalities.Objective: Characterize the phenotypic spectrum, associated conditions and response to growth-promoting therapies.Design: Retrospective international cohort study.Patients: Information from 103 individuals (57 female, 46 male) from 20 families with confirmed heterozygous ACAN mutations were included.Methods: Families with autosomal dominant short stature and heterozygous ACAN mutations were identified and confirmed using whole-exome sequencing, targeted next generation sequencing, and/or Sanger sequencing. Clinical information was collected from medical records.Results: Identified ACAN variants showed perfect co-segregation with phenotype. Adult individuals had mildly disproportionate short stature (median height: -2.8 SDS, range: -5.9 to -0.9) and histories of early growth cessation. The condition was frequently associated with early-onset osteoarthritis (12 families) and intervertebral disc disease (9 families). There was no apparent genotype-phenotype correlation between type of ACAN mutation and presence of joint complaints. During childhood, height was less affected (median height: -2.0 SDS, range: -4.2 to -0.6). In contrast to most children with short stature, the majority of children had advanced BA (BA - CA, median: +1.3y; range +0.0 to +3.7y) reflecting a reduction in remaining growth potential. Nineteen individuals had received GH with some evidence of increased growth velocity.Conclusions Heterozygous ACAN mutations result in a phenotypic spectrum ranging from mild and proportionate short stature to a mild skeletal dysplasia with disproportionate short stature and brachydactyly. In several of the families, affected individuals developed early-onset osteoarthritis and degenerative disc disease requiring intervention, suggesting dysfunction of articular cartilage and intervertebral disc cartilage. Additional studies are needed to determine the optimal treatment strategy for these patients.
|
|
| 3. |
- Gerver, Willem J. M., et al.
(författare)
-
Arm Span and Its Relation to Height in a 2- to 17-Year-Old Reference Population and Heterozygous Carriers of ACAN Variants
- 2020
-
Ingår i: Hormone Research in Paediatrics. - : S. Karger. - 1663-2818 .- 1663-2826. ; 93:3, s. 164-172
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND/OBJECTIVES: In the clinical assessment of a short or tall child, estimating body disproportion is useful to assess the likelihood of a primary growth disorder, e.g., skeletal dysplasia. Our objectives were (1) to use data from the Maastricht study on healthy children (2-17 years) to calculate relative arm span (AS) for height (H) to serve as age references for clinical purposes; (2) to assess its age and sex dependency; and (3) to investigate relative AS adjustment for age and sex in individuals with ACAN haploinsufficiency.METHODS: The Maastricht study data (2,595 Caucasian children, 52% boys, 48% girls) were re-analysed to produce reference tables and graphs for age and sex of AS - H and AS/H. Published information on AS/H in Europeans was used as reference data for adults. Relative AS from 33 patients with ACAN haploinsufficiency were plotted against reference data and expressed as standard deviation score (SDS) for age and sex.RESULTS: Mean AS - H from 2 to 17 years increased from -1.2 to +1.5 cm in boys and from -4.8 to +1.6 cm in girls. Mean AS/H increased from 0.9848 to 1.0155 in boys and from 0.9468 to 1.0028 in girls. Mean AS/H in patients with ACAN haploinsufficiency was approximately 1.0, 1.5 and 0.5 SDS in young children, adolescents and 20- to 50-year-olds, respectively, and normal thereafter.CONCLUSIONS: These reference charts can be used for 2- to 17-year-old children/adolescents. Carriers of ACAN haploinsufficiency have an elevated mean AS/H in childhood and adolescence and a slightly elevated ratio till 50 years.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
- Hudson, Lawrence N, et al.
(författare)
-
The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project
- 2017
-
Ingår i: Ecology and Evolution. - : John Wiley & Sons. - 2045-7758. ; 7:1, s. 145-188
-
Tidskriftsartikel (refereegranskat)abstract
- The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.
|
|
| 7. |
- Lui, Julian C., et al.
(författare)
-
Ezh2 mutations found in the Weaver overgrowth syndrome cause a partial loss of H3K27 histone methyltransferase activity
- 2018
-
Ingår i: Journal of Clinical Endocrinology and Metabolism. - Cary, NC, United States : Oxford University Press. - 0021-972X .- 1945-7197. ; 103:4, s. 1470-1478
-
Tidskriftsartikel (refereegranskat)abstract
- Context: Weaver syndrome is characterized by tall stature, advanced bone age, characteristic facies, and variable intellectual disability. It is caused by heterozygous mutations in EZH2, a histone methyltransferase responsible for H3K27 trimethylation. However, no early truncating mutations have been identified, suggesting that null mutations do not cause Weaver syndrome.Objective: To test alternative hypotheses that EZH2 variants found in Weaver syndrome either cause a gain of function or a partial loss of function.Design: Exome sequencing was performed in a boy with tall stature, advanced bone age, and mild dysmorphic features. Mutant or wild-type EZH2 protein was expressed in mouse growth plate chondrocytes with or without endogenous EZH2, and enzymatic activity was measured. A mouse model was generated, and histone methylation was assessed in heterozygous and homozygous embryos.Results: A de novo missense EZH2 mutation (c.1876G>A (p.Val626Met)) was identified in the proband. When expressed in growth plate chondrocytes, the mutant protein showed decreased histone methyltransferase activity. A mouse model carrying this EZH2 mutation was generated using CRISPR/Cas9. Homozygotes showed perinatal lethality while heterozygotes were viable, fertile, and showed mild overgrowth. Both homozygous and heterozygous embryos showed decreased H3K27 methylation.Conclusion: We generated a mouse model with the same mutation as our patient and found that it recapitulates the Weaver overgrowth phenotype, and demonstrated that EZH2 mutations found in Weaver syndrome cause a partial loss of function.
|
|
