Abstract：According to our previous research, there was an obvious relationship between the early death of chicken(Gallus gallus)-quail(Coturnix coturnix) hybrids and sex differentiation. Meanwhile, current widespread adapted methods to indentify sex differentiation stayed at RNA level, experimental steps complicated and easy to make mistakes, and RNA samples, which are needed to be measured, was quite difficult to preserved longer, but could not be simply employed. So it is necessary to find a more simple and accurate way to identify the early embryo's sexing. In this study, there were two sections for CHD (chromobox-helicase-DNA binding) gene DNA level sex determination, at first,a total of 116 chicken-quail hybrid embryos at different incubate stages (2.5~5 d) was treated as experiment group and 10 mg embryonic organs were used to DNA extraction; then the DNA extraction from blood of 60 sex-known quails (male and female were half-and-half) was regarded as control. Wpkci (W-linked protein kinase C inhibitor) for mRNA level was known as a mature method to identify sexing, and then it is used to check the result of embryos' sex determination in our research. The result showed that CHD 2550F/2718R could identify the sex of chicken-quail hybrid embryos accurately. The amplication size of male embryo tissues was 613 bp and two bands in female were 613 and 446 bp, respectively. The experimental results provide basic data for the chicken-quail hybrids sex determination mechanism.
