A technique for the sequential isolation of RNA and DNA from embryos developed for screening for viruses

A technique has been developed to detect RNA or DNA viruses in single embryos. This technique is based on sequential RNA and DNA isolation from the embryo and analysis of this nucleic acid by polymerase chain reaction. A constitutively expressed embryo gene (alpha subunit ATPase) is also analysed as an internal standard. Extraction of RNA was more efficient than that of DNA, however, positive results were obtained for the internal standard gene for 84% (RNA) and 30% (DNA) of embryos tested.