部分养殖鱼类存在两性生长异形的表型，因此，构建相应单性别养殖群体对水产养殖产量的提升具有产业应用价值。迄今为止，采用激素活性物质诱导产生性反转亲本是水产养殖业构建单性别群体最普遍使用的方法。本研究针对雌鲤生长快于雄鲤的两性生长异形的特性，以cyp17a1 为靶点进行了CRISPR/Cas9介导的基因编辑操作，利用cyp17a1 敲除后形成的伪雄鲤，成功构建了全雌鲤群体。首先，我们发现无论遗传性别型为XX还是XY，其cyp17a1 缺失鲤个体性腺均发育为精巢，并能正常产精。其次，利用确定的雄性特异DNA分子标记，筛选到cyp17a1 ^-/- XX伪雄个体，其具有正常的精巢发育和精子发生。将其与野生型雌鲤杂交，在8 月龄时检测后代性别，发现100%为雌性。将全雌群体和对照组雌雄混合群体各500 尾进行同塘生长对比养殖，至8 月龄或12 月龄时随机抽样检测，发现cyp17a1杂合突变雌鲤体重比同塘性别混养对照组分别高6.60%或32.66%。因此，本研究首次成功地利用基因工程技术对单基因位点进行操作，创制了全雌群体，实现了对雌鲤生长快的两性生长异形特性的应用，提升了养殖产量。

Due to sexual dimorphism in the growth of certain cultured fish species, the production of monosex fishes is desirable for the aquaculture industry. Nowadays, the most widely practiced technique available for the mass production of monosex fish populations is sex steroid-induced sex reversal. Here, a novel strategy for the successful production of all-female (AF) common carp (Cyprinus carpio L.), to take advantage of the sexual dimorphism in growth documented in this species, has been developed using genetic engineering via single gene-targeting manipulation without any exogenous hormone treatments. Male and female heterozygous cyp17a1-deficient common carp were first obtained using the clustered regularly interspaced short palindromic repeats/CRISPR-associated endonuclease 9 (CRISPR/Cas9) technique. An all-male phenotype for homozygous cyp17a1-deficient carp, regardless of the individuals' sex-determination genotypes (XY or XX), has been observed. A male-specific DNA marker newly identified in our laboratory was used to screen the neomale carp population with the XX genotype from the cyp17a1-deficient carp. These neomale carp develop a normal testis structure with normal spermatogenesis and sperm capacity. The neomale common carp were then mated with wild-type (WT) females (cyp17a1+/+ XX genotype) using artificial fertilization. All the AF offspring sample fish from the neomale-WT female mating were confirmed as having the cyp17a1+/− XX genotype, and normal development of gonads to ovaries was observed in 100.00% of this group at eight month post-fertilization (mpf). A total of 1000 carp fingerlings, 500 from the WT male and female and 500 from the neomale and WT female mating, were mixed and reared in the same pond. The average body weight of cyp17a1+/− XX females was higher by 6.60% (8 mpf) and 32.66% (12 mpf) than that of the control common carp. Our study demonstrates the first successful production of a monosex teleost population with the advantages of sexual dimorphism in growth using genetic manipulation targeting a single locus.