-
Revista Medica Del Instituto Mexicano... Sep 2023Down syndrome (DS) is the most common autosomal aneuploidy and the leading cause of intellectual disability of genetic origin worldwide. It is identified as a syndrome... (Review)
Review
Down syndrome (DS) is the most common autosomal aneuploidy and the leading cause of intellectual disability of genetic origin worldwide. It is identified as a syndrome in which the variability of its clinical manifestations and the severity of its phenotype have a multifactorial origin. Worldwide prevalence ranges between 1 per 700 live births and several factors that may be involved in the origin of DS have been proposed. Our objective was to describe updates regarding risk factors in the cytogenetic origin or cause of DS. We conducted a narrative review study in which a literature search was carried out from January to June 2022 in databases such as PubMed, EBSCO, Medigraphic, ClinicalKey, and meta-search engines such as Elsevier and Evidence Alerts. Only articles published in the last 10 years in English and Spanish were included. The search terms used were: Down syndrome, risk factors, prevention. Although DS is a very common chromosomal pathology worldwide, there is no single risk factor at the origin of meiotic or mitotic nondisjunction of chromosome 21, but rather each of the associated risk factors contributes to a greater or lesser degree to a cytogenetic predisposition in the etiology of trisomy 21. During the review it was identified that the main established risk factor associated with DS is still advanced maternal age (≥ 35 years).
Topics: Adult; Humans; Down Syndrome; Maternal Age; Nondisjunction, Genetic; Risk Factors; Female
PubMed: 37769135
DOI: 10.5281/zenodo.8316459 -
Journal of Clinical Immunology Aug 2020
Topics: Adaptive Immunity; Biomarkers; Comorbidity; Down Syndrome; History, 20th Century; Humans; Research
PubMed: 32712750
DOI: 10.1007/s10875-020-00837-z -
Free Radical Biology & Medicine Jan 2018This review focuses on the role of Aβ in AD pathogenesis in Down syndrome and current approaches for imaging Aβ in vivo. We will describe how Aβ deposits with age,... (Review)
Review
This review focuses on the role of Aβ in AD pathogenesis in Down syndrome and current approaches for imaging Aβ in vivo. We will describe how Aβ deposits with age, the posttranslational modifications that can occur, and detection in biofluids. Three unique case studies describing partial trisomy 21 cases without APP triplication, and the occurrences of low level mosaic trisomy 21 in an early onset AD patient are presented. Brain imaging for Aβ includes those by positron emission tomography and ligands (Pittsburgh Compound B, Florbetapir, and FDDNP) that bind Aβ have been published and are summarized here. In combination, we have learned a great deal about Aβ in DS in terms of characterizing age of onset of this pathology and it is exciting to note that there is a clinical trial in DS targeting Aβ that may lead to clinical benefits.
Topics: Amyloid beta-Peptides; Animals; Down Syndrome; Humans; Neuroimaging
PubMed: 28935420
DOI: 10.1016/j.freeradbiomed.2017.09.013 -
Australian Family Physician Jul 2014Noninvasive prenatal testing (NIPT) has marked a revolution in aneuploidy screening because it allows a simple maternal blood test to detect Down syndrome in a fetus... (Review)
Review
BACKGROUND
Noninvasive prenatal testing (NIPT) has marked a revolution in aneuploidy screening because it allows a simple maternal blood test to detect Down syndrome in a fetus with a very high level of accuracy (at least 99.5% with a false-positive rate of 0.2%).
OBJECTIVE
To describe the new tests that have become available and their place in antenatal screening to help GPs and their patients make informed decisions about their use.
DISCUSSION
Results are available from 12 weeks gestation, giving a high level of reassurance for Down syndrome early in pregnancy. There are concerns, however, that the test is being offered without proper counselling and that women may not have a 12-week ultrasound to exclude significant structural abnormalities, therefore decreasing the early detection of severe abnormalities. In addition, the test is expensive and therefore prohibitive for many women and their families.
Topics: Aneuploidy; Down Syndrome; Female; Genetic Counseling; Humans; Pregnancy; Prenatal Diagnosis; Reproducibility of Results
PubMed: 25006601
DOI: No ID Found -
Molecular Medicine (Cambridge, Mass.) Mar 2018Trisomy of chromosome 21 (TS21) is the most common autosomal aneuploidy compatible with postnatal survival with a prevalence of 1 in 700 newborns. Its phenotype is... (Review)
Review
Trisomy of chromosome 21 (TS21) is the most common autosomal aneuploidy compatible with postnatal survival with a prevalence of 1 in 700 newborns. Its phenotype is highly complex with constant features, such as mental retardation, dysmorphic traits and hypotonia, and variable features including heart defects, susceptibility to Alzheimer's disease (AD), type 2 diabetes, obesity and immune disorders. Overexpression of genes on chromosome-21 (Hsa21) is responsible for the pathogenesis of Down syndrome (DS) phenotypic features either in a direct or in an indirect manner since many Hsa21 genes can affect the expression of other genes mapping to different chromosomes. Many of these genes are involved in mitochondrial function and energy conversion, and play a central role in the mitochondrial dysfunction and chronic oxidative stress, consistently observed in DS subjects.Recent studies highlight the deep interconnections between mitochondrial dysfunction and DS phenotype. In this short review we first provide a basic overview of mitochondrial phenotype in DS cells and tissues. We then discuss how specific Hsa21 genes may be involved in determining the disruption of mitochondrial DS phenotype and biogenesis. Finally we briefly focus on drugs that affect mitochondrial function and mitochondrial network suggesting possible therapeutic approaches to improve and/or prevent some aspects of the DS phenotype.
Topics: Animals; Down Syndrome; Humans; Mitochondria
PubMed: 30134785
DOI: 10.1186/s10020-018-0004-y -
Down's Syndrome, Research and Practice... Oct 2008Animal models are extensively used in genetics, neuroscience and biomedical research. Recent studies illustrate the usefulness and the challenges of research utilising... (Review)
Review
Animal models are extensively used in genetics, neuroscience and biomedical research. Recent studies illustrate the usefulness and the challenges of research utilising genetically engineered mice to explore the developmental biology of Down syndrome. These studies highlight many of the issues at the centre of what we understand about Down syndrome, and may one day point to useful ways to improve quality of life for people living with Down syndrome.
Topics: Animals; Brain Chemistry; Disease Models, Animal; Down Syndrome; Gene Dosage; Humans; Mice
PubMed: 19026279
DOI: 10.3104/updates.2054 -
Medicina (Kaunas, Lithuania) Mar 2021The role of bruxism in children and adolescents with Down syndrome, the most often diagnosed congenital syndrome, is still unclear. Therefore, this study aims to conduct... (Review)
Review
The role of bruxism in children and adolescents with Down syndrome, the most often diagnosed congenital syndrome, is still unclear. Therefore, this study aims to conduct a narrative review of the literature about bruxism in children and adolescents with Down syndrome to identify the prevalence, risk factors, and possible treatments of this disorder. Although an accurate estimate of its prevalence could not be inferred, it appears that bruxism is more prevalent in Down syndrome individuals rather than in the general pediatric population. No gender difference was observed, but a reduction in its prevalence was described with increasing age (around 12 years). The variability in the diagnostic techniques contributed to the heterogeneity of the literature data. Clinicopathological features of Down syndrome, such as muscle spasticity, oral breathing, and a predisposition to obstructive sleep apnea, may suggest a higher prevalence of bruxism in this patient group. Finally, given the paucity of studies on the management of bruxism in this population, it was not possible to outline a standard protocol for the non-invasive treatment of cases in which an observational approach is not sufficient.
Topics: Adolescent; Child; Down Syndrome; Humans; Prevalence; Risk Factors; Sleep Apnea, Obstructive; Sleep Bruxism
PubMed: 33804484
DOI: 10.3390/medicina57030224 -
Frontiers in Endocrinology 2023To analyze and determine the safety and efficacy of growth hormone (GH) treatment in Down syndrome (DS) pediatric patients and to weigh ethical aspects involved. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To analyze and determine the safety and efficacy of growth hormone (GH) treatment in Down syndrome (DS) pediatric patients and to weigh ethical aspects involved.
DESIGN
Systematic review and mini meta-analysis of the literature.
METHODS
A search was performed in PubMed, Embase, Scopus, and PsycINFO through August 2022. Eligible studies included those who answered at least one of the following two questions: 1) What is the effect of growth hormone treatment in children with Down syndrome? 2) What are the ethical arguments in favor and against growth hormone treatment for children with Down syndrome? Multiple reviewers independently screened each article for eligibility.
RESULTS
In total sixteen reports detailed medical effects of GH treatment in pediatric DS patients and eight studies dealt with ethical aspects of GH treatment. Treatment with GH resulted in significantly higher growth velocity in patients with DS. The ethical complexity is great but does not present insurmountable difficulties to the therapeutic option.
CONCLUSIONS
As GH treatment is safe and effective for short-term height growth, GH therapy should be considered in long-term treatment of DS children.
Topics: Humans; Child; Human Growth Hormone; Down Syndrome; Body Height; Insulin-Like Growth Factor I
PubMed: 37152958
DOI: 10.3389/fendo.2023.1135768 -
Developmental Period Medicine 2017Down syndrome (DS) is the most common chromosomal aberration and genetically determined cause of intellectual disability. DS patients often present with some congenital... (Review)
Review
Down syndrome (DS) is the most common chromosomal aberration and genetically determined cause of intellectual disability. DS patients often present with some congenital defects and chronic diseases, including early onset dementia, which affects 70% of DS patients over 55 years of age and has a clinical presentation similar to Alzheimer disease (AD). The symptoms of DS originate from excessive genetic material within the "critical region" of the 21st chromosome. The "critical region" encompasses genes potentially associated with increase risk of dementia, e.g. the APP gene (amyloid beta precursor protein) which leads to excessive amyloid beta production. Post-mortem studies of DS patients' brains revealed diffuse deposition of the insoluble form of amyloid beta (Aβ), which is a characteristic feature of AD. Moreover, those changes were commonly observed in subjects > 31 years old. The pathomechanisms of AD have not been fully elucidated and scientists are still searching for new risk factors that may contribute to the development of this common illness. Recent research proved that lipid disturbance, especially disorders in the metabolism of HDL (high density lipoprotein) may play a crucial role in this pathogenic process. There are many studies examining lipid and lipoprotein concentration in the DS population, but up to now there are insufficient studies comparing these parameters with memory impairment, which may be a useful model for better understanding of the dementia pathomechanism.
Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Dementia; Down Syndrome; Humans; Lipid Metabolism; Middle Aged; Young Adult
PubMed: 28551695
DOI: 10.34763/devperiodmed.20172101.6973 -
Down's Syndrome, Research and Practice... Jul 2007Clear speech can often be challenging for people with Down syndrome. The shape of the hard palate in the top of the mouth influences speech production. A new paper...
Clear speech can often be challenging for people with Down syndrome. The shape of the hard palate in the top of the mouth influences speech production. A new paper reports detailed measures of the shape and size of the hard palate among children with Down syndrome.
Topics: Child; Cleft Lip; Cleft Palate; Down Syndrome; Humans; Language Development; Palate, Hard; Speech; Speech Intelligibility
PubMed: 17692182
DOI: 10.3104/updates.2050