College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China.
Tianjin Aoqun Sheep Industry Academy Company, Tianjin, 300000, PR China; Tianjin Aoqun Animal Husbandry Co., Ltd., Tianjin, 301607, PR China.
Theriogenology. 2022 Feb;179:155-161. doi: 10.1016/j.theriogenology.2021.11.023. Epub 2021 Nov 29.
Cryptochrome 2 (Cry2) gene regulates circadian rhythm and affects reproduction and pregnancy. Therefore, this study aimed to explore polymorphisms of the Cry2 gene and their associations with litter size at different parity in Australian White (AuW) ewes. Five putative insertion or deletion mutations within the Cry2 gene were selected to study their association with litter size. Two novel deletion mutations were identified in intronic region of Cry2 gene and were genotyped by agarose gel electrophoresis and DNA sequencing. The polymorphism information content (PIC) indicated that both mutations were low polymorphism in tested groups. Statistical analysis revealed that the P1-Del-6-bp was significantly correlated with litter size at third parity (P = 0.010), in which individuals with insertion/deletion (ID) genotype had larger litter size than insertion/insertion (II) genotype (P < 0.05). Whereas, the P2-Del-6-bp was significantly correlated with litter size at first parity (P = 0.036), in which individuals with insertion/insertion (II) genotype had larger litter size than insertion/deletion (ID) genotype (P < 0.05). Collectively, these findings may provide new insights to expedite molecular breeding in sheep through marker-assisted selection strategies (MAS).
CRY2 基因调控生物钟，影响繁殖和妊娠。因此，本研究旨在探讨澳大利亚白绵羊（AuW） CRY2 基因多态性及其与不同胎次产仔数的关系。选择 CRY2 基因内的 5 个假定插入或缺失突变，研究其与产仔数的关系。在 CRY2 基因的内含子区域发现了两个新的缺失突变，并通过琼脂糖凝胶电泳和 DNA 测序进行了基因分型。多态信息含量（PIC）分析表明，两个突变在检测群体中均为低多态性。统计分析表明，P1-Del-6-bp 与第三胎产仔数显著相关（P=0.010），具有插入/缺失（ID）基因型的个体产仔数大于插入/插入（II）基因型（P<0.05）。而 P2-Del-6-bp 与第一胎产仔数显著相关（P=0.036），具有插入/插入（II）基因型的个体产仔数大于插入/缺失（ID）基因型（P<0.05）。总之，这些发现可能为通过标记辅助选择策略（MAS）加速绵羊分子育种提供新的见解。
