Buccal Smear
From GenderWiki
The buccal smear test, as it applies to gender, is a clinical sex/gender identity test where a brush or swab is used to collect a sample of cells from the surface of the cheek for laboratory analysis. The specific buccal smear used for sex/gender identification is known as the Sex Chromatin Test.
It is used in cases where newborns have indeterminate external organs, in criminal or post-mortem investigations, and to determine or verify gender for participation in various sports.
