A Parent's Guide to the Genetics of Down Syndrome

Hartway, Sarah A.

doi:10.1097/01.anc.0000346092.50981.c0

Cited by 10 publications

(15 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The occurrence of DS is strongly dependent on maternal age, and advanced maternal age remains the only well-documented risk factor for maternal meiotic non-disjunction. With a maternal age of 45 years, the risk is one in 30 to 50 live births 18. However, understanding of the basic mechanism behind the maternal age effect is lacking.…”

Section: Discussionmentioning

confidence: 99%

Congenital heart disease and Down syndrome: various aspects of a confirmed association

Benhaourech

Drighil

Hammiri

2016

CVJA

View full text Add to dashboard Cite

SummaryBackgroundCongenital heart disease (CHD) is frequently described in patients with Down syndrome (DS) and is the main cause of death in this population during the first two years of life. The spectrum of CHD patterns in DS varies widely worldwide; this variation could be due to sociodemographic, genetic and geographic factors.MethodsA six-year retrospective, descriptive study was carried out from December 2008 to October 2014, based on the Paediatric Unit CHD registry of Ibn Rochd University Hospital. Clinical, echocardiographic and outcomes data were collected and sorted according to confirmation of the syndrome.ResultsAmong 2 156 patients with CHD, 128 were identified with Down syndrome. The genders were equally represented (gender ratio 1) and the median age at diagnosis was 9.5 months (2 days to 16 years). The median age of mothers at delivery was 39 years (16–47). Of the 186 CHD lesions reported, the most common was atrioventricular septal defect (AVSD, 29%), followed by ventricular septal defect (VSD,21.5%) and atrial septal defect (ASD, 19.9%). The most common associations of CHD were AVSD + ASD (10%) and VSD + ASD (7.8%). Surgery was the most common modality of treatment (54.3%). The overall mortality rate was 14.1%.ConclusionOur study confirmed that the profile and type of CHD in DS in the Moroccan setting exhibited slight differences in the distribution of these CHDs compared with European neighbours and other Western countries. Further studies are needed to determine which variables have an impact on these differences.

show abstract

Section: Discussionmentioning

confidence: 99%

Congenital heart disease and Down syndrome: various aspects of a confirmed association

Benhaourech

Drighil

Hammiri

2016

CVJA

View full text Add to dashboard Cite

show abstract

“…First, the “ developmental instability hypothesis ” evokes a loss of genetic balance (among the hundreds of genes) in chromosome 21 leading to an imbalance of gene expression in pathways that control development (Shapiro et al, ; Shapiro, ). Second, the “ gene‐dosage effect hypothesis ” states that the excess of chromosome 21 genes (three copies instead of the usual two) results in an abnormal phenotype (Patterson and Costa, ; Hartway, ). It has also been proposed that both these mechanisms could act in conjunction (Patterson and Costa, ; Hartway, ).…”

Section: Etiopathophysiologymentioning

confidence: 99%

“…Second, the “ gene‐dosage effect hypothesis ” states that the excess of chromosome 21 genes (three copies instead of the usual two) results in an abnormal phenotype (Patterson and Costa, ; Hartway, ). It has also been proposed that both these mechanisms could act in conjunction (Patterson and Costa, ; Hartway, ).…”

Section: Etiopathophysiologymentioning

confidence: 99%

“…The various causes of DS include nondisjunction (95%), translocation (3.2%), and mosaicism (1.8%) associated with chromosome 21 (Kava et al ). Nondisjunction occurs because of aberrant cell division during the formation of ovum or sperm, resulting in an extra chromosome 21 (24 chromosomes in a gamete) (NDSS, ; Hartway, ); thus, after fertilization, the zygote will have 47 chromosomes instead of 46. As the word implies, translocation refers to an additional copy of chromosome 21 that is partially or fully translocated to another chromosome (Hartway, ; NDSS, ).…”

Section: Etiopathophysiologymentioning

confidence: 99%

See 1 more Smart Citation

Down syndrome—A narrative review with a focus on anatomical features

Arumugam

Raja²,

Venugopalan³

et al. 2015

Clinical Anatomy

View full text Add to dashboard Cite

Down syndrome (DS) is the most common aneuploidy of chromosome 21, characterized by the presence of an extra copy of that chromosome (trisomy 21). Children with DS present with an abnormal phenotype, which is attributed to a loss of genetic balance or an excess dose of chromosome 21 genes. In recent years, advances in prenatal screening and diagnostic tests have aided in the early diagnosis and appropriate management of fetuses with DS. A myriad of clinical symptoms resulting from cognitive, physical, and physiological impairments caused by aberrations in various systems of the body occur in DS. However, despite these impairments, which range from trivial to fatal manifestations, the survival rate of individuals with DS has increased dramatically from less than 50% during the mid-1990s to 95% in the early 2000s, with a median life expectancy of 60 years reported recently. The aim of this narrative review is to review and summarize the etiopathology, prenatal screening and diagnostic tests, prognosis, clinical manifestations in various body systems, and comorbidities associated with DS. Clin. Anat. 29:568-577, 2016. © 2015 Wiley Periodicals, Inc.

show abstract

“…Down syndrome is characterized by a distinctive phenotypic profi le and is the most common chromosome disorder resulting in cognitive and developmental disability (Ranweiler, 2009). Th e syndrome was fi rst described by John Langdon Down in 1866; however, it wasn't until 1959 that the association between Down syndrome and chromosome #21 was discovered (Hartway, 2009). Down syndrome is considered to be a genetic disorder, as the aff ected individual has additional genetic material that is either all or part of chromosome #21.…”

Section: About Down Syndromementioning

confidence: 99%