Amplification and differentiation of the DNA of an abortigenic (type 1) and a respiratory (type 4) strain of equine herpesvirus by the polymerase chain reaction.

This research paper discusses how scientists were able to differentiate between two types of equine herpesvirus using DNA amplification and restriction digestion techniques.

Methods

• The study used DNA derived from cultures of equine fetal kidney cells infected with either herpesvirus type 1, which causes abortion in horses, or herpesvirus type 4, associated with respiratory disease.
• The polymerase chain reaction (PCR), a method used to rapidly make millions to billions of copies of a specific DNA sample, was used to amplify the DNA. This made it easier to study as there was more of it.
• A single pair of oligonucleotide primers were used in the PCR. Primers are short strands of DNA that serve as a starting point for DNA synthesis, so they helped in the amplification process.

Results

• Once the DNA was sufficiently amplified, the researchers used restriction endonuclease digestion to cut the DNA into smaller segments. This makes the DNA easier to analyze.
• The enzyme PvuII was used to perform the digestion. This is an enzyme that recognizes specific sequences of DNA and cuts them at particular points.
• The resulting DNA fragments were then separated and visualized using electrophoresis, a technique that separates DNA, RNA, or protein molecules based on their size and charge. It’s like running a comb through the tangled DNA strands and lining them up by length.

Conclusion

• The researchers were able to identify differences between the two types of equine herpesvirus using the method of amplification by PCR, followed by restriction digestion with PvuII, and analysis by gel electrophoresis. These differences, known as restriction fragment length polymorphisms, allowed the researchers to distinguish between herpesvirus type 1 and type 4.
• This study highlights the potential of these molecular techniques for diagnosing the type of equine herpesvirus present, which could help in the treatment and prevention of disease in horses.