Related Experiment Video
Updated: May 22, 2026
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
Ambiguous genitalia: what prenatal genetic testing is practical?
Margaret P Adam1, Patricia Y Fechner, Linda A Ramsdell
1Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington, USA. margaret.adam@seattlechildrens.org
American Journal of Medical Genetics. Part A
|May 15, 2012
Summary
Prenatal diagnosis of ambiguous genitalia is challenging. Karyotype with SRY FISH is most useful, while targeted rare disorder testing has low yield without family history.
Area of Science:
- Genetics
- Pediatrics
- Reproductive Medicine
Background:
- Prenatal detection of ambiguous genitalia and chromosome-phenotype discordance has increased.
- Genetic testing options for disorders of sex development (DSD) are available, but their utility is unclear.
Purpose of the Study:
- To assess the rate of prenatal detection of ambiguous genitalia in DSD cases.
- To evaluate the prenatal diagnostic workup and postnatal outcomes.
- To determine the usefulness of various prenatal genetic tests for DSD.
Main Methods:
- Retrospective review of 140 individuals evaluated at a DSD clinic (1994-2011).
- Analysis of prenatal detection rates, diagnostic testing performed, and postnatal genetic confirmation.
Main Results:
- 24% of individuals with DSD were identified prenatally.
- Most common postnatal diagnoses included hypospadias (17%) and 21-hydroxylase deficiency (14%).
- Prenatal testing methods varied widely; karyotype with SRY FISH was most useful for suspected ambiguous genitalia without other anomalies.
Conclusions:
- Prenatal karyotype with SRY FISH is recommended for suspected ambiguous genitalia.
- Consider prenatal testing for Smith-Lemli-Opitz syndrome (46,XY) and congenital adrenal hyperplasia (46,XX).
- Targeted molecular testing for rare DSDs lacks utility without a family history.
