Cytogenetic Testing: Routine Chromosome Analysis (Karyotype)

Also known as: karyotype, karyotyping, congenital blood test, cytogenetic testing.

What is cytogenetic testing: routine chromosome analysis?

Chromosomes are the threadlike structures within each cell which contain the genetic material passed from parent to child. Your child’s cells have 46 chromosomes, which carry thousands of genes which are responsible for your child’s characteristics.

There are 23 pairs of chromosomes. 22 are found in both sexes (autosomes), one pair (sex chromosomes) is present either as XY (male) or XX (female). In the reproductive cells-eggs and sperm only contain half the normal number; that is 23. Each half from each parent gives rise to the 46 found in the child.

A chromosomal analysis or karyotyping is a test which examines the number and structure of your child’s chromosomes. This test helps in the diagnosis of genetic diseases, some birth defects and certain abnormalities of the blood.

What happens during the procedure?

A standard small blood sample is drawn from a vein in your child’s arm (sometimes other samples like bone marrow may be used) and the sample is sent to the genetics laboratory for testing.

Is any special preparation needed?

No special preparation is needed for this test.

What are the risk factors?

There are slight risks of infection, bleeding, bruising, swelling or damage to nearby structures when the blood is drawn.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: April 08, 2024 02:43 PM

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