Also known as: SNP Array, Microarray Testing, SNP Microarray, CGH Microarray, CGH Array« Back to test list
Microarray analysis can detect submicroscopic deletions and duplications of genetic material across all chromosomes.
In the first instance, this test is for an affected patient and can provide diagnostic and prognostic information. Once a potential abnormality is identified, studies of relatives may be necessary to clarify the genetic diagnosis and the risks to relatives.
The presence of a pathogenic abnormality provides specific diagnostic and prognostic information. Further family studies may clarify the recurrence risk in relatives.
The absence of a pathogenic abnormality does not necessarily exclude a clinical diagnosis.
Microarrays can also detect deletions and duplications that are of unknown clinical significance or which have variable clinical outcomes. Rarely, deletions or duplications which are associated with a clinically significant disorder unrelated to the presentation of the patient may be detected. The report will provide advice regarding the interpretation of such findings.
This is an assay for heritable mutations. It may raise issues of ethics or consent that are different from most other investigations ordered in the routine care of a patient. The interpretation of the result may also be dependent on the family history and the interpretation of other studies.
The relative amounts of genetic material from hundreds of thousands of small regions from all chromosomes are measured. Deviations from the expected values can identify deletions and duplications.
Sonic Genetics uses a Sullivan Nicolaides Pathology (SNP) microarray, which also provides additional genotype information compared with a CGH microarray, and as such can identify large regions of homozygosity.
This test can be requested by any medical practitioner.
2-5 mL blood in EDTA. Specimens may be collected by the requesting practitioner or at any Sonic Healthcare pathology collection centre.
To help ensure the quality of the test, a genetic test should be done with a dedicated sample whenever possible i.e. a sample collected specifically for that test rather than a sample that is used for multiple tests.
We also recommend that the patient or another adult check the labelling of request forms and sample tubes.
Please include details of any clinical abnormalities in the patient being tested, and the results of chromosome or array studies in relatives.