Background: Prenatal diagnosis for Fetal Chromosomal anomalies currently relies on assessment of risk followed by a combination of biochemical and nuchal translucency. Trisomy 21 is the most common trisomy that is associated with intellectual disability. Pregnant women who receive a prenatal diagnosis of trisomy 21 currently have the option of continuing or terminating their pregnancy, but no f...

Trisomy 21 mosaicism in a woman with two children with trisomy 21 Down's syndrome* Summary. Trisomy 21 mosaicism was identified by fluorescent quinacrine banding in a phenotypically normal mother, who gave birth to two children with trisomy 21 Down's syndrome. Trisomy 21 Down's syndrome associated with maternal mosaicism was first described by Smith et al in 1962. Since then there have been at ...

OBJECTIVE To assess the potential performance of screening for fetal trisomies 21, 18 and 13 by cell-free DNA (cfDNA) analysis of maternal blood using the IONA® test. METHODS This was a nested case-control study of cfDNA analysis of maternal plasma using the IONA test. Samples were obtained at 11-13 weeks' gestation, before chorionic villus sampling, from 201 euploid pregnancies, 35 with tris...

OBJECTIVE To investigate the maternal serum concentration of human placental growth hormone (hPGH) in trisomy 21 and trisomy 18 pregnancies at 11 to 13 weeks of gestation and to examine the possible association between fetal nuchal translucency (NT) thickness and maternal serum free beta-human chorionic gonadotrophin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A). METHODS The m...

Although it is clear that trisomy 21 causes Down syndrome, the molecular events acting downstream of the trisomy remain ill defined. Using complementary genomics analyses, we identified the interferon pathway as the major signaling cascade consistently activated by trisomy 21 in human cells. Transcriptome analysis revealed that trisomy 21 activates the interferon transcriptional response in fib...

OBJECTIVES To derive a model and examine the performance of first-trimester screening for trisomy 18 by maternal age, fetal nuchal translucency (NT) thickness, and maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A). METHODS Prospective combined screening for trisomy 21 was performed at 11 + 0 to 13 + 6 weeks in 56 893 singleton ...

OBJECTIVE.Our goal was to determine whether the third ventricle is significantly enlarged among neonates with trisomy 21, compared with infants without clinical signs of trisomy 21. This enlargement might be related to hypoplasia of the structures surrounding the third ventricle. These structures participate in cognitive development, and hypoplasia in this area may be responsible for some of th...