trisomy 21


Also found in: Dictionary, Thesaurus, Acronyms, Encyclopedia, Wikipedia.
Related to trisomy 21: trisomy 21 syndrome

trisomy 21

trisomy 21

trisomy 21

Down syndrome, mongolism Pediatrics A chromosomal dysgenesis caused by partial or complete duplication of all or part of chromosome 21 appears 3 times; in some only some cells contain the chromosomal defect–ie, mosaicism Clinical MR, microcephaly, short stature, a characteristic facial dysmorphia–flat hypoplastic facies, short/flat nose, upward slanting eyes–Mongolian slant; inner corner of the eyes often has a rounded fold of skin–epicanthal fold; small, low-set ears, thickened, protruding and fissured tongue, joint laxity, pelvic dysplasia, broad hands and feet with shortened digits, a single transverse palmar or simian crease, lenticular opacification, cardiac defects–eg, PDA, endocardial cushion defects, Fallot's tetralogy, esophageal atresia, duodenal atresia, muscle spasms, ↑ risk of ALL, retardation of growth and development is typical; most never reach average adult height Risk of DS ↑ with maternal age–0.7/1000 births ≤ age 30; 34.6/1000 ≥ age 45 Prognosis Compatible with long-term survival Incidence 1:900. See Maternal age.

trisomy 21

chromosomal abnormality (three rather than two chromosome 21) causing development of type of Down's syndrome

Patient discussion about trisomy 21

Q. Can Down syndrome occur again? A few years ago, at the age of 32 my sister gave birth to a child that was diagnosed with Down syndrome. Now, at the age of 37 she's pregnant again. Can she have another baby with Down? Does the fact she has a baby with Down means she has higher risk for a second baby with Down?

A. - Older women especially after 35 years
- Previuosly child with Down Syndrome

Video link
http://www.thedoctorsvideos.com/video/585/Downs-Syndrome

DrMFK

Q. assessment of down syndrom

A. down syndrome is a very easy diagnosis - it just need a chromosome check and seeing 3 (instead 2) chromosomes number 21. -

http://learn.genetics.utah.edu/content/disorders/whataregd/down/

Q. what does enlarged heart mean? is it linked to down syndrome? My wife is 16 weeks pregnant. we did a prenatal US and we were told that the baby hes an enlarged heart and that we are advised to do amniocentesis. A friend of mine had a baby with down syndrome, and he was toled that if they have done this procedure, the doctors could have find it on time and abort the pregnancy. Is there a clear connection between the enlarged hart and the fact that the doctor advised us to do this procedure to down syndrome?

A. Down syndrome is associated with several kinds of heart problems. those problems can cause an enlarged heart but usually it will appears as a post-natal complication.
The protocol that most obstetrics use is that if there is anything abnormal in the US there is an automatic referral to an amniocentesis procedure.
the US has a lot of false alarms, so they must check with the more accurate procedure.

More discussions about trisomy 21
References in periodicals archive ?
One of these fetuses had trisomy 21 and the other a 17p13.
By evaluating cell-free DNA found in maternal blood including accurate measurement of the fetal fraction of DNA, the test assesses the risk of Trisomy 21 (Down syndrome) in the fetus.
Individuals with Trisomy 21 may also have insufficient accommodative abilities at a young age.
1998, FISH studies of sperm of fathers of paternally derived cases of trisomy 21 : no evidence for an increase in aneuploidy.
Using these techniques, 61 cases of trisomy 21 were identified during the first trimester.
Most persons with DS have trisomy 21 present in all cells.
Some evidence has been presented of a possible association between the hernia of Morgagni and trisomy 21 (5).
It's caused by an extra copy of chromosome 21, so the disorder is also known as trisomy 21.
Down's syndrome, or trisomy 21, is a complex genetic disease caused by an extra copy of chromosome 21.
Natera, a leading innovator in reproductive and prenatal genetic testing, today announced that the company's non-invasive prenatal screening test, Panorama[TM], will launch on March 1 for the detection of trisomy 21 (Down syndrome), trisomy 18 (Edwards syndrome), trisomy 13 (Patau syndrome) and select sex chromosome abnormalities, such as monosomy X (Turner's syndrome).
With the recognition of fetal DNA methylation markers on chromosome 21 (24), this approach can potentially be applied for the noninvasive prenatal detection of trisomy 21.
NEW YORK -- It's important to offer patients a range of options for trisomy 21 screening, Dr.