Array Chrome - Chromosomal Microarray Test

CGH Chromosome array test is offered to children to rule out genetic causes of developmental delays, intellectual disabilities, autism spectrum, psychiatric illness, unexplained seizures & neuromuscular conditions.
This technique is not limited by tissue culture failure which affects traditional techniques like karyotyping

Chromosomal arrays are typically ordered for individuals with:

?A first-degree family member who has been diagnosed with a syndrome or chromosomal abnormality (deletion, duplication, or inversion).
?An older sibling with autism or a sibling with a genetic disorder.
?Family history of a chromosome abnormality.
?Congenital abnormalities.
?Autism spectrum disorder, especially if there is a history of intellectual disability and/or

Array CGH detects chromosomal change, sub microscopic abnormalities, copy number variation (CNV)

CGH Chromosome array test requires a blood sample. A tourniquet (elastic) band is placed tightly on the upper arm. The patient is then asked to make a fist. This helps in the build-up of blood filling the veins. The skin is disinfected before needle insertion and the blood sample is collected in vacutainer

The test is performed on a blood sample, so there is nothing to do before the test. If a child will be having his or her blood drawn, parents may want to give something to drink and eat before the test (such as candy or juice), so their child will not feel lightheaded when the blood is drawn. Parents can also call their local lab and find out how long they expect their child's blood draw will take

Array CGH can detect aneuploidies, large deletions & copy number variants. Parents will genetic counselling to understand results better, assess prognosis, understand recurrence risk and decide on management and preventive measures
This technique will not detect balanced chromosome rearrangements (which do not result in deletion or duplication of genetic material) and low level mosaicism

The results of the test are usually presented as a numerical report with a graphical display of the chromosomes. The report will indicate whether any chromosomal abnormalities have been detected, as well as their type, size, and location.

The normal result of a chromosomal array test is that the chromosomes are found to be structurally normal and the number of chromosomes is consistent with the individual's sex.

You do not feel any kind of pain or discomfort during the Array Chrome test procedure. There will be a little discomfort when your blood is drawn from a vein in the arm.

Chromosomal microarray analysis is a very safe test. There are no known health risks associated with this test.

The main benefit of having a chromosomal microarray is that it can detect abnormalities that may not be seen on a standard karyotype. The results from this test can help the geneticist determine whether a child has developmental problems because of an underlying genetic condition and whether any changes in medical management or additional testing would benefit the child.
 

Other tests that may be ordered with a chromosomal array test include a karyotype, fluorescence in situ hybridization (FISH), and a microarray.  

Some labs may also recommend additional tests, including a Fragile X, or possibly genetic testing for epilepsy if the individual was diagnosed with autism.  Any questions about these tests should be directed to the ordering physician.

• Chromosomal array CGH
• Comparative genomic hybridization (CGH)
• Chromosomal array
• Chromosomal microarray analysis