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Updated: Jun 28, 2026
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
High-resolution array genomic hybridization in prenatal diagnosis.
1Department of Medical Genetics, University of British Columbia, and Medical Genetics Research Unit, Child and Family Research Institute, Children's and Women's Hospital, Vancouver, British Columbia, Canada. frid@interchange.ubc.ca
Prenatal Diagnosis
|November 15, 2008
Summary
Array genomic hybridization (AGH) detects smaller chromosomal changes than conventional methods, identifying more fetal genomic imbalances. However, uncertain results and unknown risks limit its current prenatal diagnostic use.
Area of Science:
- Genetics
- Prenatal Diagnostics
- Genomic Medicine
Background:
- Conventional cytogenetic methods have limitations in detecting small chromosomal abnormalities.
- Genomic imbalances are a significant cause of birth defects and developmental disorders.
Purpose of the Study:
- To evaluate the utility of Array Genomic Hybridization (AGH) as a prenatal test for fetal genomic imbalance.
- To compare the diagnostic yield of AGH with conventional cytogenetic analysis.
Main Methods:
- Genome-wide AGH was employed to detect chromosomal gains or losses.
- Comparison of AGH findings with conventional cytogenetic analysis in prenatal settings.
Main Results:
- AGH can detect chromosomal changes 100 times smaller than conventional methods.
- AGH identifies fetal genomic imbalances at least twice as frequently as conventional analysis.
- AGH testing yields a higher proportion of results with uncertain clinical significance.
Conclusions:
- AGH offers a more sensitive and frequent detection of fetal genomic imbalances prenatally.
- The clinical significance of many AGH findings (CNVs) is not well-established, complicating patient counseling.
- Current use of AGH for prenatal diagnosis should be restricted to high-risk pregnancies or clinical trials due to unknown risks and benefits.
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