A buccal (pronounced "buckle") smear is the painless removal of a sample of cells from the inside of your mouth (cheek) for study.
Sex chromatin test; Buccal swab
How the Test is Performed
Your health care provider will gently scrape the inside of the cheek with a small spatula to collect cells for testing. Sometimes, you can do this yourself.
How to Prepare for the Test
Follow the collection instructions as directed by your provider.
How the Test will Feel
You will feel a scraping sensation as cells are removed from the cheek.
Why the Test is Performed
This test is done to get cells for chromosome or DNA analysis, most often for genetic testing.
This test may also help establish sexual identity. When the test is used in this way, it's called the sex chromatin test.
There are no risks with this test.
Roy S. Molecular anatomic pathology: principles, techniques, and application to immunohistologic diagnosis. In: Dabbs DJ, ed. Diagnostic Immunohistochemistry. 6th ed. Philadelphia, PA: Elsevier; 2022:chap 24.
Review Date: 24/04/2023
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright ©2019 A.D.A.M., Inc., as modified by University of California San Francisco. Any duplication or distribution of the information contained herein is strictly prohibited.
Information developed by A.D.A.M., Inc. regarding tests and test results may not directly correspond with information provided by UCSF Health. Please discuss with your doctor any questions or concerns you may have.