中国科学院水生生物研究所鱼类功能基因组学学科组负责的草鱼全基因组序列图谱绘制完成。该成果由水生生物研究所、中国科学院国家基因研究中心和中山大学等机构合作完成，相关研究成果于5月4日在线发表于《自然—遗传学》杂志。

    据该所研究员汪亚平介绍，该研究采用鸟枪法测序策略，分别对一尾雌性和一尾雄性草鱼进行了全基因组测序，成功获得雌性(0.9GB)和雄性(1.07GB)草鱼基因组组装序列。其中，雌性草鱼为人工减数分裂雌核发育个体，因其基因组杂合度显著降低，获得了高质量的组装序列;雄性草鱼为野生个体，基因组组装质量明显下降，但为雄性基因组特异片段的挖掘提供了基础数据。

    草鱼以草食性特征而得名，它们如何从水草中汲取营养以支持其快速生长一直是研究者关注的问题。该研究结果表明，草鱼基因组中并不存在纤维素降解酶基因。比较转录组分析发现，草鱼在草食性转化过程中，肠道中昼夜节律相关基因的表达模式发生了重设，肝脏中甲羟戊酸通路和类固醇生物合成通路被激活。草鱼可能通过持续高强度的食物摄入，获取足够的可利用营养以维持其快速生长。

    草鱼作为鲤科鱼类的代表性物种，其全基因组序列的解析，将为这种鱼类重要经济性状相关基因的发掘和养殖品种的遗传改良提供关键技术支撑，同时，也将为鱼类基因组演化、性别决定及分化机制等理论研究奠定重要基础。

    原文链接：The draft genome of the grass carp (Ctenopharyngodon idellus) provides insights into its evolution and vegetarian adaptation

    原文摘要：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.