三角帆蚌HcTyp-1基因珍珠层颜色性状相关SNP筛选及图谱定位

Detection of nacre colour-related SNPs and genetic mapping of HcTyp-1 gene in Hyriopsis cumingii

本实验室根据前期研究发现,HcTyp-1基因可能参与了三角帆蚌贝壳珍珠层颜色的形成。本实验根据HcTyp-1基因cDNA设计引物,比较筛选获得了8个SNP位点并分析了这些位点与内壳色的相关性,然后对HcTyp-1基因进行了图谱定位。通过研究这些多态性位点与贝壳珍珠层颜色性状相关性发现,C+3057T位点基因型仅在a参数上存在显著差异,G+2985T和T+3006C 2个位点基因型分别在L、b及a、dE上存在显著差异,A+2834C、C+2919T和G+2986T这3个SNPs位点基因型在L、a及dE上均存在显著差异。连锁不平衡结果显示,HcTyp-1基因上除C+2912T、C+2983A这2个位点,其他6个位点具有显著差异,位点之间都存在强连锁不平衡。单倍型分析结果显示,单倍型T2和T4在白色群体中出现的频率极显著高于在紫色群体中出现的频率,T6和T8两种单倍型在紫色群体中出现的频率极显著高于白色群体。因此HcTyp-1基因的部分SNPs可作为三角帆蚌不同内壳色贝壳辅助育种的候选分子标记位点。另外,本研究还将HcTyp-1基因定位在三角帆蚌LG16连锁群上,这为进一步解析该基因调控珍珠颜色形成的分子机制奠定了基础。

According to previous studies, we found that HcTyp-1 gene may be involved in the formation of nacre color in shell of Hyriopsis cumingii. Primers were designed based on the cDNA sequence of HcTyp-1 gene in H. cumingii, and 8 SNPs were obtained by comparative screening and the correlation between SNPs and nacre colourrelated traits was analyzed. Moreover, the location of HcTyp-1 gene on genetic map was studied. The study of the relationship between these polymorphic sites and shell nacre color traits found that, C+3057T showed a significant difference in the “a”;G+2985T and T+3006C had significant difference of L, b and a, dE respectively. Moreover, A+2834C, C+2919T and G+2986T all had significant difference in L, a and dE. Linkage disequilibrium analysis showed that there were 6 SNPs in high linkage disequilibrium except C+2912T and C+2983A. The result of haplotype analysis indicated that the frequency of T2 and T4 in the white mussels was significantly higher than that of purple group, but T6 and T8 were higher in purple group. The results suggested that the polymorphic loci in HcTyp-1 could be potential genetic markers for future molecular selection of different nacre color in H. cumingii. Furthermore, we mapped HcTyp-1 gene on LG16 of the previous linkage map, which will lay the foundation for the further study of the molecular mechanisms about this gene.