Research Note: Determination of the Sex of Chickens by a Biotin-Labeled Deoxyribonucleic Acid Probe

Repeating units of the W chromosome-specific, XhoI-family repetitive DNA of chickens have been cloned and sequenced. The recombinant plasmid carrying the .7 kilobase (kb) W chromosome-specific repeating unit was labeled by biotinylated deoxyuridine 5'-triphosphate and used to determine the sex of White Leghorn chicken by two DNA hybridization techniques. Hybrids formed were detected by the streptavidin-alkaline phosphatase method. By Southern blot hybridization, XhoI-.7 kb, XhoI-1.1 kb, and EcoRI-1.3 kb fragments were detected in the genomic DNA from the female White Leghorn but not in the DNA from the male. By dot-blot hybridization, which is the most convenient way to detect a specific nucleotide sequence, the difference between male and female could be clearly detected not only using purified DNA samples but also using blood cells or even blood itself as samples.