Karyotyping is a test using whichyour doctor examines your genes. The entire process ofcollecting cell samplesand theiranalysisto find defects in chromosomes is called “Karyotype”. Karyotyping is a way for a medical practitioner to examine chromosomes and determine if the chromosomes have any structural issues or abnormalities.
Each cell in the body of a person contains chromosomes. They are made up of genetic material that get passed onby their parents. They are made up of DNA, which is what determines how every person develops.
A cell must pass along genetic informationto its daughter cells while it divides. The chromosomes of a cell when it isn’t in the division process are not arranged in an ordered manner. They rather appear spread out. Thenew cells which are forming have chromosomes that arearranged in pairs longitudinally during the division process.
These dividing cells are examined by a karyotype test. Note that the chromosome pairs in a dividing cell are arranged according to their appearance and size. This allows your doctor to easily identify if any of the chromosomes have been damaged or missing.
This test proves extremely helpful—
A genetic condition can be indicated by an abnormal number or malformed or disarranged chromosomes. There are many genetic conditions, but Turner syndrome and Down syndrome are two of the most common.
Karyotyping is a method that can detect many genetic disorders. This test can identify chromosomal defects in women with premature ovarian failure. This test can also be used to identify the Philadelphia chromosome. This chromosome is a sign of chronic myelogenous lymphoma (CML).
To diagnose birth defects like Klinefelter syndrome, babies can be karyotype-tested before they are born. Klinefelter syndrome is a condition in which a babyhas an additional X chromosome.
How should the preparation be done and what are the risks of this test?
Preparation for karyotyping will depend on how your doctor takes a blood sample to test. There are many ways to take samples, including a bone marrow biopsy, a simple blood draw, and an amniocentesis. While bone marrow biopsy is a procedure whereinthe bloodsample is taken from the spongy tissues within a bone, an amniocentesis is a process that involves taking a sample of uterus’s amniotic fluid.
These testing procedures can sometimes cause complications, but such instances are rare. The procedure of having your blood drawn and having your bone marrow biopsy done can pose a slight risk for infection or bleeding. And there is a very low chance of miscarriage during amniocentesis.
People who areon chemotherapy, their test results could be affected. Your chromosomes can be damaged by chemotherapy, and this will show up in the test.
How is the test performed?
First, the concerned person’s cells are taken as a sample.The cells samples may be from many different tissues such as the placenta, the amniotic fluid, blood and the bone marrow.
There are many methods that can be used to collect samples depending on the area being tested. If amniotic fluid is needed to test, the doctor may use amniocentesis.
Once the sample is taken, it is puton a lab dish where the cells grow. Then the sample, or more specifically, the cells in it are stained. This allows a health practitioner to examine the chromosomes with a microscope.
After staining the cells,they are examined to determine if there are any abnormalities in the chromosomes. These abnormalities could include broken chromosomes that get attached to other chromosomes, additionalportions of chromosomes, missing portions of chromosomes and extrachromosomes.
The laboratory technician can view the chromosomes’ number, shape, as well as size. This information can be used to determine if there is a genetic abnormality in the person whose sample it is.
What to deduce from the results of the test?
Normal test results will reveal 46 chromosomes. Out of the 46 chromosomes 2are called sex-chromosomes. These twoareresponsible for the gender of the individual being tested. 44 are autosomes. Autosomes do not determine the person’s sex. While males only have one X chromosome, females have two.
The test result may show abnormalities. This could be due to genetic conditions or syndromes. Occasionally,a positive karyotype report might notreflectin the individual’s body. To confirm the abnormality, it’s best to repeat the test.
Your doctor may recommend a karyotype in many cases. Some of the cases are—
- Children and infants with medical conditions that suggest a chromosomal anomaly but have not been diagnosed.
- Adults with symptoms that suggest a chromosomal abnormality.
- It may be possible to do a genetic karyotype for infertility. Some chromosomal abnormalities can go undiagnosed until adulthood, as we have already mentioned. A Turner syndrome-suffering woman or a man having a Klinefelter variant may not know they have it until they experience infertility.
- Some cases like translocation Down syndrome (a hereditary condition), may require parents to go through this testing. It is important to remember that Down syndrome is usually not a hereditary condition, but a chance mutation.
- The testing for stillbirth is often performed by a karyotype.
- A parental karyotype may be able to give clues about the causes of recurring miscarriages. At least half of miscarriages are thought to be caused by chromosomal abnormalities like trisomy 16.
- Karyotype tests may be used to diagnose leukaemia. For example, it might look for the Philadelphia chromosome in people with acute lymphocytic leukaemia or chronic myelogenousleukaemia.
If you want to know what the Karyotyping Test Cost is, then it is advisable that you talk to your doctor. The prices vary depending on certain factors.