Abstract: A multiplex polymerase chain reaction (mPCR) assay was developed to simultaneously detect target gene (bt), selectable marker gene (nptⅡ) and reporter gene (gus) of T-DNA from 18 transgenic birch. Three sets primers were designed and synthesized based on transferred vector sequence. Under the optimized conditions, the assay yielded a 247 bp DNA fragment from bt gene, 449 bp DNA fragment from nptⅡ gene, 668 bp DNA fragment from gus gene. The results of the mPCR using positive control showed that the sensitive and simultaneous detection of foreign genes were as normal as simplex PCR assay, also a little higher. After simultaneous detecting 18 transgenic birches using mPCR, we found that the method could decrease the risk of contamination, save time and reduce the cost and so on. The mPCR method provides a useful rapid technique for detecting multiple genes in transgenic birch and offers data on transgenic copy number, flanking sequences of transgenic T-DNA, and some other transgenic integration researches.

Key words: birch, foreign gene, T-DNA, mutiplex PCR