Scientists at the Delhi-based National Institute of Immunology (NII) have developed a method for sex-specific identification of raw meats in cattle, buffalo, goat and sheep using the polymerase chain reaction (PCR) technique -- used for copying and amplifying the target deoxyribonuclic acid (DNA). Says S M Totey of the NII, "The results of our research can be of immense use in the meat industry, where identification of male and female meat is necessary to check adulteration of costly meat with cheaper ones."

Adds Totey, "Several (other) methods for the detection of the origin of meat in food products are known to us. However, these methods do not tell whether the meat is from a male or a female animal."

In the new method, the PCR assay is conducted on DNA extracted from raw muscle tissue of male and female animals to identify whether it belonged to a male or a female animal.

The genetic basis of sexual differentiation in mammals lies in the XX- and XY-chromosome, which are present in females and males, respectively. The presence or absence of Y-chromosome is the primary determinant of sex. The PCR assay technique helps in recognising and amplifying the Y-chromosome specific sequences, which are present only in the males.

---ASHISH VACHHANI.