Nuclear sexing is a technique for genetic sex determination in those species where XX chromosome pair is present.
Nuclear sexing can be done by identifying Barr body, a drumstick like appendage located in the rim of the nucleus in somatic cells.
Barr body is the inactive X chromosome which lies condensed in the nucleus of somatic cells.
A typical human (or other XY-based organism) female has only one Barr body per somatic cell, while a typical human male has none.
These cells are cultured, and treated with chemicals such as colcemid to arrest mitosis in metaphase.