Wang, Y., Lu, Y., Zhang, Y., Ning, Z., Li, Y., Zhao, Q., Lu, H., Huang, R., Xia, X., Feng, Q., Liang, X., Liu, K., Zhang, L., Lu, T., Huang, T., Fan, D., Weng, Q., Zhu, C., Lu, Y., Li, W., Wen, Z., Zhou, C., Tian, Q., Kang, X., Shi, M., Zhang, W., Jang, S., Du, F., He, S., Liao, L., Li, Y., Gui, B., He, H., Ning, Z., Yang, C., He, L., Luo, L., Yang, R., Luo, Q., Liu, X., Li, S., Huang, W., Xiao, L., Lin, H., Han, B., Zhu, Z. (2015) The draft genome of the grass carp (Ctenopharyngodon idellus) provides insights into its evolution and vegetarian adaptation. Nature Genetics. 47(6):625-31.
The grass carp is an important farmed fish, accounting for ∼16% of global freshwater aquaculture, and has a vegetarian diet. Here we report a 0.9-Gb draft genome of a gynogenetic female adult and a 1.07-Gb genome of a wild male adult. Genome annotation identified 27,263 protein-coding gene models in the female genome. A total of 114 scaffolds consisting of 573 Mb are anchored on 24 linkage groups. Divergence between grass carp and zebrafish is estimated to have occurred 49-54 million years ago. We identify a chromosome fusion in grass carp relative to zebrafish and report frequent crossovers between the grass carp X and Y chromosomes. We find that transcriptional activation of the mevalonate pathway and steroid biosynthesis in liver is associated with the grass carp's adaptation from a carnivorous to an herbivorous diet. We believe that the grass carp genome could serve as an initial platform for breeding better-quality fish using a genomic approach.