Gene transcription analysis of carrot allergens by relative quantification with single and duplex reverse transcription real-time PCR.

Single and duplex real-time polymerase chain reaction (PCR) systems have been developed to quantify specific mRNA transcription of genes coding for the major Daucus carota allergen isoforms Dau c 1.01 and Dau c 1.02. Methods were tested with samples from the local market. Whereas the gene transcription levels for Dau c 1.01 were consistently high in all investigated samples, significant differences for the Dau c 1.02 transcription could be demonstrated in randomly collected market samples. The gene transcription level for the minor Dau c 1.02 variant is about one log below Dau c 1.01. Both formats, single or duplex real-time methods, exhibit ideal cycle threshold (CT) ranges and good reproducibility. In particular, the easily performed duplex real-time PCR system is potentially suited for the selection of hypoallergenic varieties and studying the impact of post-harvesting or environmental conditions.