兼容型maizeSNP384标记筛选与玉米杂交种DNA指纹图谱构建

为加强玉米品种管理和知识产权保护,评估确定了一套兼容多技术平台,适于玉米分子鉴定的SNP位点组合,该组合包含384个位点;构建了335个玉米杂交种SNP-DNA指纹,幵针对位点和样品从各个角度迚行分析。384个位点全部分布在基因内区域,显示了较好的多态性; MAF、PIC、DP平均值分别为0.39、0.36、0.60, 384个位点中88%的位点MAF值高于0.30, 98%的位点PIC值高于0.30, 98%的位点DP值高于0.50。对335个玉米杂交种迚行遗传相似系数两两比较, GD (1-Nei遗传距离)的变异范围为0.60～0.99, GD≥0.98、0.95、0.90者分别占比0.10%、0.38%、1.40%;GS(相同等位基因比)的变异范围为0.50～0.99,GS≥0.98、0.95、0.90者分别占比0.03%、0.11%、0.35%。从384个位点中抽取最优位点组合, 12个位点组合时品种识别率为0.99, 20个位点组合能够识别335个品种。综上所述,本研究报道的384个核心SNP位点具有兼容多平台、高稳定性、高重复性、高品种区分能力,利用核心位点构建了335个玉米杂交种SNP-DNA指纹,为玉米品种分子鉴定、指纹数据构建以及分子育种提供了关键数据支撑。

Screening of compatible maizeSNP384 markers and the construction of DNA fingerprints of maize varieties

In order to improve the management of maize varieties and the protection of intellectual property rights, a compatible multiple platform loci combination maizeSNP384 was developed as a means of identifying varieties of maize. SNP-DNA fingerprints of 335 maize hybrids were constructed. All the 384 SNPs were located in the intra-genic region, showing good polymorphism. The average MAF, PIC, and DP of 384 loci were 0.39, 0.36, and 0.60, respectively. MAF in 88% of the 384 loci was most than 0.30, PIC in 98% was most than 0.30, and DP in 98% was most than 0.50. Pairwise comparative analysis of 335 maize hybrids using genetic similarity showed that the range of variation of GD (1-Nei genetic distance) was 0.60-0.99, and the ratios of GD value greater than or equal to 0.98, 0.95, and 0.90 were 0.10%, 0.38%, and 1.40%, respectively. The range of variation of GS (same allele ratio) was 0.50-0.99, and the ratios of GS value greater than or equal to 0.98, 0.95, and 0.90 were 0.03%, 0.11%, and 0.35%, respectively. The optimal locus combination was extracted from 384 SNPs, with the variety discrimination power of 0.99 when 12 SNPs were extracted; the combination of 20 SNPs was able to identify all 335 varieties. In summary, 384 core SNPs reported in this study are compatible with multiple platforms, highly stable, highly repeatable and having high variety discrimination power. SNP-DNA fingerprints of 335 maize hybrids were constructed based on these core SNPs, which provides key data support for molecular identification, fingerprint data construction, and molecular breeding of maize.