Single nucleotide polymorphisms (SNPs) are the smallest unit of genetic variation and are abundant in animal and plant genomes. They are an excellent choice for studies on plant genetics and breeding. Many SNPs have been discovered in the barley genome and it is hoped that shortly SNPs will be identified that are directly linked to key traits measured during the DUS testing of varieties. At SASA we are using the relatively new method of temperature switch PCR (TSP) to differentiate barley varieties on the basis of their SNPs. If successful this method can be used by other laboratories that do not have access to hi-tech equipment such as DNA sequencers or real-time PCR machines as the TSP products can be separated by simple agarose gel electrophoresis. Preliminary results are encouraging and all of the varieties tested can be differentiated using 25 markers.
Dendogram constructed from the TSP SNP profiles for 12 barley varieties