Ballantyne Maeve, Taylor Lorna, Hu Tuanjun, Meunier Dominique, Nandi Sunil, Sherman Adrian, Flack Brenda, Henshall John M, Hawken Rachel J, McGrew Mike J
The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom.
Centre for Tropical Livestock Genetics and Health, University of Edinburgh, Edinburgh, United Kingdom.
Front Cell Dev Biol. 2021 Sep 29;9:726827. doi: 10.3389/fcell.2021.726827. eCollection 2021.
In birds, males are the homogametic sex (ZZ) and females are the heterogametic sex (ZW). Here, we investigate the role of chromosomal sex and germ cell competition on avian germ cell differentiation. We recently developed genetically sterile layer cockerels and hens for use as surrogate hosts for primordial germ cell (PGC) transplantation. Using propagated and cryopreserved PGCs from a pedigree Silkie broiler breed, we now demonstrate that sterile surrogate layer hosts injected with same sex PGCs have normal fertility and produced pure breed Silkie broiler offspring when directly mated to each other in Sire Dam Surrogate mating. We found that female sterile hosts carrying chromosomally male (ZZ) PGCs formed functional oocytes and eggs, which gave rise to 100% male offspring after fertilization. Unexpectedly, we also observed that chromosomally female (ZW) PGCs carried by male sterile hosts formed functional spermatozoa and produced viable offspring. These findings demonstrate that avian PGCs are not sexually restricted for functional gamete formation and provide new insights for the cryopreservation of poultry and other bird species using diploid stage germ cells.
在鸟类中，雄性为同配性别（ZZ），雌性为异配性别（ZW）。在此，我们研究染色体性别和生殖细胞竞争在鸟类生殖细胞分化中的作用。我们最近培育出了基因不育的蛋用公鸡和母鸡，用作原始生殖细胞（PGC）移植的替代宿主。利用来自一个谱系的丝羽肉鸡品种的增殖和冷冻保存的PGC，我们现在证明，注射了同性PGC的不育替代蛋用宿主具有正常的繁殖力，并且在种公种母替代交配中相互直接交配时能产生纯种丝羽肉鸡后代。我们发现，携带染色体为雄性（ZZ）的PGC的雌性不育宿主形成了功能性的卵母细胞和卵子，受精后产生了100%的雄性后代。出乎意料的是，我们还观察到，雄性不育宿主携带的染色体为雌性（ZW）的PGC形成了功能性精子并产生了可存活的后代。这些发现表明，鸟类PGC在功能性配子形成方面不受性别限制，并为利用二倍体阶段生殖细胞冷冻保存家禽和其他鸟类物种提供了新的见解。
