Aim:A mammalian somatic cell from a normal (XX) female typically has one fully active X chromosome. The other X chromosome is transcriptionally inert, heterochromatic, late replicating and termed Barr body. Present study was conducted to assess the accuracy of Barr body in sex determination.

Study Design: A blind study was conducted over 50 male and 50 females. Buccal scrapings were taken with wooden spatula and a thin smear was prepared followed by staining with Hematoxylin and Eosin.  In each slide, 100 cells having vesicular nuclei and distinct cellular outline were counted and percentage of sex chromatin was calculated.

Result: Among females, mean % of Barr body count was significantly higher (p<0.001) as compared to that of males. It was found to be 88% sensitive, 74% specific and overall diagnostic accuracy of 81%.

Conclusion: Buccal smear evaluation has enabled chromosomal sex to be determined with considerable accuracy.