Karyotyping and Why It's Important

A karyotype test is basically a test that analyzes your chromosomes. It tells you how many chromosomes a person has and looks at the structure of each chromosome individually. A karyotype can be performed on any tissue but most often it is done from a blood sample, a sample of amniotic fluid or a piece of placenta obtained through chorionic villi sampling. Karyotyping is a complex process that involves growing the cells, obtaining the chromosomes, staining the chromosomes, analyzing the chromosomes and reporting the results.

A karyotype test is a critical step in determining if someone has Down syndrome. People with Down syndrome have an extra number 21 chromosome. This extra number 21 chromosome can occur in three different ways - full trisomy 21, translocation Down syndrome and mosaic Down syndrome. Only a karyotype test can tell you which form of Down syndrome your child has and what the chance is to have another child with Down syndrome.

Learn more about the steps involved in making a karyotype.