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Updated: Jul 5, 2026
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
Three cases of tetrasomy 9p
S Dhandha1, W A Hogge, U Surti
1Department of Genetics, Magee-Womens Hospital, Pittsburgh, Pennsylvania 15213, USA.
American Journal of Medical Genetics
|November 29, 2002
Summary
Tetrasomy 9p is a chromosomal disorder with recognizable prenatal and birth findings. Early diagnosis is aided by characteristic ultrasound and physical features, with mosaic cases showing better survival.
Area of Science:
- Genetics
- Medical Genetics
- Prenatal Diagnosis
Background:
- Tetrasomy 9p is a rare chromosomal abnormality.
- Characterizing its phenotype is crucial for diagnosis and management.
- Prenatal diagnosis is increasingly feasible.
Observation:
- Three cases of tetrasomy 9p are presented, two diagnosed prenatally.
- Characteristic ultrasound findings include intrauterine growth restriction, ventriculomegaly, cleft lip/palate, and renal anomalies.
- Distinct facial features are observed at birth, including hypertelorism, broad nasal bridge, cleft lip/palate, ear anomalies, and micrognathia.
Findings:
- A recognizable phenotype for tetrasomy 9p is emerging.
- Prenatal ultrasound findings can suggest the diagnosis.
- Facial dysmorphia is a key postnatal indicator.
Implications:
- Early identification of tetrasomy 9p through prenatal screening is possible.
- Recognizing the phenotype aids in timely diagnosis and genetic counseling.
- Understanding severity predictors, like mosaicism, improves prognostic accuracy.
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