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Updated: May 31, 2026
09:30
Pre-Implantation Genetic Testing for Aneuploidy on a Semiconductor Based Next-Generation Sequencing Platform
Published on: August 17, 2022
Copy-number changes in prenatal diagnosis.
Melissa Strassberg1, Gary Fruhman, Ignatia B Van den Veyver
1Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.
Expert Review of Molecular Diagnostics
|July 13, 2011
Summary
Prenatal genetic testing is expanding. Array-based comparative genomic hybridization offers broader detection of chromosomal abnormalities, potentially replacing karyotyping for all pregnant individuals.
Area of Science:
- Genetics
- Prenatal Diagnostics
- Medical Technology
Background:
- Prenatal genetic disease detection was previously limited to high-risk pregnancies.
- Advances in screening and reduced risks of invasive procedures support broader access to prenatal diagnosis.
- Newer technologies enable simultaneous testing for more genetic conditions than traditional methods.
Purpose of the Study:
- To review the current use of array-based comparative genomic hybridization (aCGH) in prenatal diagnosis.
- To evaluate the potential of aCGH to replace karyotyping for prenatal genetic testing.
Main Methods:
- Review of current literature and guidelines on prenatal diagnostic technologies.
- Comparison of chromosomal microarray analysis (CMA) with standard karyotyping and fluorescence in situ hybridization (FISH).
- Assessment of aCGH's established role in pediatric and adult diagnostics.
Main Results:
- Chromosomal microarray analysis (CMA) allows simultaneous testing for a wider range of genetic conditions compared to karyotyping.
- CMA is already a recommended first-line diagnostic test for suspected genetic disorders in non-prenatal settings.
- Recent data suggest improved screening for conditions like Down syndrome and lower risks associated with invasive procedures.
Conclusions:
- Array-based comparative genomic hybridization (aCGH) is a powerful tool for prenatal diagnosis.
- aCGH is predicted to become the primary method for detecting chromosomal abnormalities prenatally.
- The expansion of prenatal genetic testing aims to provide comprehensive analysis for all pregnant individuals.
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Sequencing of the human genome has opened up several best-kept secrets of the genome. Scientists have identified thousands of genome variations that exist within a population. These variations can be a single nucleotide or a larger chromosomal variation.
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
01:17Karyotyping
Overview
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