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Nucleotide binding site (NBS) profiling, a new method was used to map resistance gene analogues (RGAs) in cauliflower (Brassica oleracea var. botrytis). This method allows amplification and the mapping of genetic markers anchored in the conserved NBS encoding domain of plant disease resistance genes. AFLP was also performed to construct the cauliflower intervarietal genetic map. The aim of constructing genetic map was to identify potential molecular markers linked to important agronomic traits that would be particularly useful for development and improving the species. Using 17 AFLP primer combinations and two degeneration primer/enzyme combinations, a total of 234 AFLP markers and 21 NBS markers were mapped in the F2 population derived from self-pollinating a single F1 plant of the cross AD White Flower x C-8. The markers were mapped in 9 of major linkage groups spanning 668.4 cM, with an average distance of 2.9 cM between adjacent mapped markers. The AFLP markers were well distributed throughout the linkage groups. The linkage groups contained from 12 to 47 loci each and the distance between two consecutive loci ranged from 0 to 14.9 cM. NBS markers were mapped on 8 of the 9 linkage groups of the genetic map. Most of these markers were organized in clusters. This result demonstrates the feasibility of the NBS-profiling method for generating NBS markers for resistance loci in cauliflower. The clustering of the markers mapped in this study adds to the evidence that most of them could be real RGAs.

To evaluate the methylation status of the 5' CpG islands in FHIT gene using plasma and tissue samples from cervical cancer patients and find a novel marker for non-invasive diagnosis of cervical cancer, methylation-specific PCR (MSP) was employed to examine CpG island methylation in FHIT gene in 151 pretreatment plasma samples and 30 tumor tissue samples obtained from cervical cancer patients. MSP product was cloned and sequenced directly. CpG island methylation of FHIT was detected in 31.13% of the plasma samples, and in 53.33% of the tissue samples. The total concordant rate of methylation status between plasma and tissue samples in FHIT gene was 80.00%. We found a strong positive correlation between FHIT methylation in the plasma and the clinical stage and histological grade of the tumor. The data showed that CpG island methylation of the FHIT gene is prevalent in the plasma and tissue samples from cervical cancer patients. FHIT detection may be used as a non-invasive marker for diagnosis of cervical cancer and prognostic treatment evaluation.

The homology-based candidate gene method was used to identified the specific PCR markers linked to cytoplasmic male sterility (CMS) in cauliflower( Brassica oleracea var botrytis.). Searching the DNA and protein data-base of NCBI , correlative genes or open reading frames were identified . Analysis of biosoft, based on the conservative regions ,five primers were designed . Among them, only primer P9/P10 produced a 313- bp specific fragment. Identified by individual plant testing , analysis of RT-PCR and dot blot ,this fragment was only existed in CMS cauliflower knxd612. Analysis of the sequence indicated it was high homologous(98%) with orf138 of Ogura CMS radish. Primary result suggested that the cytoplasmic type of CMS cauliflower knxd612 may belong to Ogura type. This research offered a good foundation to further investigate the CMS mechanism of cauliflower in molecular level.