Overview
The Cytogenetics Laboratory at Cincinnati Children's Hospital Medical Center offers Microarray testing, an advancement in cytogenetic technology that allows us to detect cytogenetic imbalances that are smaller than what can be detected through routine chromosome analysis.
Testing will detect the loss (deletion) or gain (duplication) of chromosomal regions. Cincinnati Children's Cytogenetics Laboratory offers two options for Microarray testing.
Microarray SNP (MA-SNP for postnatal specimens)
Microarray SNP (MA-SNP) testing uses BeadChip technology with a SNP based array (Illumina HD Human610-quad BeadChip platform) that has over 610,000 markers, allowing for maximizing the number of separate chromosomal regions examined. It is used to detect chromosomal imbalances throughout the genome. The resolution of this array can detect imbalances that are as small as 80-100 kilobases. This array can detect imbalances related to hundreds of common microdeletion/microduplication syndromes, subtelomeric deletions or duplications, and at thousands of loci throughout the genome, but can also be used to detect imbalances that may not be well described. It also may be useful to further define breakpoints in imbalances that are already known.
Testing will only detect the loss (deletion) or gain (duplication) of chromosomal regions represented on the arrays. Balanced or low level mosaic chromosome changes will not be identified with this technology. Traditional chromosome analysis is recommended before proceeding with Microarray testing.
The launch of Microarray SNP testing for clinical use through the Cytogenetics Laboratory at Cincinnati Children's is very exciting. This technology is new, and the uses for this testing and related testing will continue to expand.
Please contact us directly with suggestions for expanding the use of this new technology at cytogenetics@cchmc.org or by calling 513-636-4474.
Our Prenatal SNP (Single Nucleotide Polymorphism) Array is designed to detect cytogenetic imbalances (gains or losses of DNA) that are smaller than what can be detected through routine chromosome analysis. This array is designed to detect imbalances throughout the genome. The SNP array, with over 610,000 markers, can detect imbalances related to hundreds of microdeletion/microduplication syndromes, in addition to imbalances that have not been well described.
Testing will only detect the loss (deletion) or gain (duplication) of chromosomal regions represented on the arrays. Balanced or low-level mosaic chromosome changes will not be identified with this technology. The array is also not designed to detect point mutations or other changes associated with single gene disorders. If a specific genetic diagnosis is suspected, please contact the laboratory for testing that may be recommended.
Indications for Prenatal Microarray:
Prenatal SNP Array testing could be offered when there is a suspicion of a chromosome imbalance. This is an ideal test for fetuses with abnormal ultrasound findings that are suggestive of a chromosome imbalance. Prenatal array might also be offered for other indications, such as a family history of mental retardation or birth defects, or for characterization of an abnormality found on prenatal chromosome analysis.
