Screening for the rice blast resistance gene Pi-ta using LNA displacement probes and real-time PCR

Single nucleotide polymorphisms (SNPs) will become a molecular breeding tool of increasing significance as a growing range of SNP data becomes available. In order for these markers to be incorporated into breeding programs, simple, high throughput and low cost detection methods need to be available. We have developed such an assay using LNA containing displacement probes for the Pi-ta gene, an important blast resistance gene in rice. This assay gave superior performance in comparison with TaqMan MGB probes and was able to accurately identify the presence of low frequency genotypes in artificially created mixed samples. The ability to pool samples for screening purposes offers the potential to significantly increase throughput and reduce per sample detection cost, particularly for low frequency alleles.