Trisomy 9
| Trisomy 9 | |
|---|---|
Chromosome 9 | |
| Prognosis | Invariably fatal none treatment |
Full trisomy 9 is a rare and fatal
mosaicism
) or in cases of partial trisomy (trisomy 9p) in which cells have a normal set of two entire chromosomes 9 plus part of a third copy, usually of the short arm of the chromosome (arm p).
Presentation
Symptoms vary, but usually result in
heart murmurs and a webbed neck.[1]
Trisomy 9p is one of the most frequent autosomal anomalies compatible with long survival rate. A study of five cases showed an association with Coffin–Siris syndrome, as well as a wide gap between the first and second toes in all five, while three had brain malformations including dilated ventricles with hypogenesis of the corpus callosum and Dandy–Walker malformation.[2]
Diagnosis
Trisomy 9 can be
cordocentesis, and can be suggested by obstetric ultrasonography.[citation needed
]
Because trisomy 9 may appear with
karyotyping for diagnosis.[3]
References
External links
- NORD - National Organization for Rare Disorders, Inc. Chromosome 9, Trisomy 9p (Multiple Variants)
- NORD - National Organization for Rare Disorders, Inc. Chromosome 9, Trisomy Mosaic