This testing is an advance in cytogenetic technology that allows us to detect cytogenetic imbalances that are smaller than what can be detected through routine chromosome analysis. This test will be an invaluable tool for diagnosis in patients with a variety of indications when a chromosomal imbalance is suspected, but cannot be detected through traditional chromosome analysis.
Cincinnati Children’s Cytogenetics Laboratory offers testing that will detect the loss (deletion) or gain (duplication) of chromosomal regions.
Microarray SNP (MA-SNP)
testing uses BeadChip technology to examine more than 1 million separate chromosomal regions. We use the Infinium Assay with the Illumina HD HumanOmni1-quad BeadChip platform in our SNP (single- nucleotide polymorphism) based platform. This array is used to detect chromosomal imbalances throughout the genome. The resolution of this array can detect imbalances that are as small as 80-100 Kb with gaps in coverage of 1 megabase or less. This array can detect imbalances that may not be well-described. It may also be useful to further define breakpoints in imbalances that are already known.
Patients with chromosome imbalances may not have classic presentations, so with other technologies it may be difficult to decide which specific test to do. Now all of these regions can be examined with one test. Balanced or mosaic chromosome changes may not be identified with this technology. Traditional chromosome analysis is recommended before proceeding with pediatric cytogenetic microarray testing.