Qu Cunmin, Jia Ledong, Fu Fuyou, Zhao Huiyan, Lu Kun, Wei Lijuan, Xu Xinfu, Liang Ying, Li Shimeng, Wang Rui, Li Jiana
Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400716, China.
Engineering Research Center of South Upland Agriculture of Ministry of Education, Southwest University, Beibei, Chongqing, 400716, China.
BMC Genomics. 2017 Mar 14;18(1):232. doi: 10.1186/s12864-017-3607-8.
B. napus (oilseed) is an important source of edible vegetable oil, and its nutritional and economic value is determined by its fatty acid composition and content.
Using the Brassica 60 K SNP array, we performed a genome-wide association study of fatty acid composition in a population of 520 genetically diverse oilseed accessions. Using the PCA + K model in TASSEL 5.2.1, we identified 62 genomic regions that were significantly associated with the composition of seven fatty acids, and five consensus regions that mapped to the A2, A8, A9, C1, and C3 chromosomes, respectively, of the Brassica napus Darmor-bzh genome. We then identified 24 orthologs of the functional candidate genes involved in fatty acid biosynthesis, excluding BnaA.FAE1 and BnaC.FAE1 on the A8 and C3 homologous genome blocks, which are known to have critical roles in the fatty acid biosynthesis pathway, and potential orthologs of these genes (e.g., LACS9, KCR1, FAB1, LPAT4, KCS17, CER4, TT16, and ACBP5).
Our results demonstrate the power of association mapping in identifying genes of interest in B. napus and provide insight into the genetic basis of fatty acid biosynthesis in B. napus. Furthermore, our findings may facilitate marker-based breeding efforts aimed at improving fatty acid composition and quality in B. napus.
甘蓝型油菜（油菜籽）是食用植物油的重要来源，其营养和经济价值由其脂肪酸组成和含量决定。
利用甘蓝型油菜60K SNP芯片，我们对520份遗传多样的油菜籽种质资源群体的脂肪酸组成进行了全基因组关联研究。使用TASSEL 5.2.1中的主成分分析（PCA）+K模型，我们鉴定出62个与七种脂肪酸组成显著相关的基因组区域，以及五个分别定位到甘蓝型油菜Darmor-bzh基因组的A2、A8、A9、C1和C3染色体上的共有区域。然后，我们鉴定出24个参与脂肪酸生物合成的功能候选基因的直系同源基因，不包括A8和C3同源基因组块上已知在脂肪酸生物合成途径中起关键作用的BnaA.FAE1和BnaC.FAE1，以及这些基因的潜在直系同源基因（如LACS9、KCR1、FAB1、LPAT4、KCS17、CER4、TT16和ACBP5）。
我们的结果证明了关联作图在鉴定甘蓝型油菜中感兴趣基因方面的强大作用，并为甘蓝型油菜脂肪酸生物合成的遗传基础提供了见解。此外，我们的发现可能有助于旨在改善甘蓝型油菜脂肪酸组成和品质的基于标记的育种工作。
