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Karyotyping
Definition:
Karyotyping is a test to identify chromosome abnormalities as the cause of malformation or disease. This test can: - Count the number of chromosomes
- Look for structural changes in chromosomes
The results may indicate genetic changes linked to a disease. Text Continues Below
Alternative Names:
Chromosome analysis How the test is performed:
The test can be performed on a sample of blood, bone marrow, amniotic fluid, or placental tissue.
Chromosomes contain thousands of genes that are stored in DNA, the basic genetic material. The specimen is grown in tissue culture in the laboratory. Then, the cells are harvested, and the chromosomes are stained and viewed under the microscope. They are photographed to provide a karyotype, which shows the arrangement of the chromosomes. Certain abnormalities can be identified through the number or arrangement of the chromosomes. How to prepare for the test:
There is no special preparation for the blood test. To test amniotic fluid, an amniocentesis is performed. Testing on placental tissue is done after a chorionic villus sampling or after a miscarriage. A bone marrow specimen requires a bone marrow biopsy. For infants and children: The preparation you can provide for this test depends on your child’s age, previous experience, and level of trust. For specific information regarding how you can prepare your child, see the following topics: How the test will feel:
How the test will feel depends on whether the sample procedure is venipuncture (having blood drawn), amniocentesis, or bone marrow biopsy.
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