Gamma-irradiation depletes endogenous germ cells and increases donor cell distribution in chimeric chickens.
The production of chimeric birds is an important tool for the investigation of vertebrate development, the conservation of endangered birds, and the development of various biotechnological applications. This study examined whether gamma (γ)-irradiation depletes endogenous primordial germ cells and enhances the efficiency of somatic chimerism in chickens. An optimal irradiation protocol for stage X embryos was determined after irradiation at various doses (0, 100, 300, 500, 600, 700, and 2,000 rad). Exposure to 500 rad of γ-irradiation for 73 s significantly decreased the number of primordial germ cells (P < 0.0001). Somatic chimera hatchlings were then produced by transferring blastodermal cells from a Korean Oge into either an irradiated (at 500 rad) or intact stage X White Leghorn embryo. An analysis of feather color pattern and polymerase chain reaction-based species-specific amplification of various tissues of the hatchlings confirmed chimerism in most organs of the chick produced from the irradiated recipient; a lesser degree of chimerism was observed in the non-irradiated control recipient. In conclusion, the exposure of chick embryos to an optimized dose of γ-irradiation effectively depleted germ cells and yielded greater somatic chimerism than non-irradiated control embryos. This technique can be applied to interspecies reproduction or the production of transgenic birds.
WCU Biomodulation Major, Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, Korea.
Kyung Je
KJ
Park
Seok Jin
SJ
Kang
Tae Min
TM
Kim
Young Mok
YM
Lee
Hyung Chul
HC
Lee
Gwonhwa
G
Song
Jae Yong
JY
Han
D000818:Animals; D001756:Blastoderm / Q000166:cytology*; D017690:Cell Transplantation; D002642:Chick Embryo; D002678:Chimera / Q000196:embryology*; D017931:DNA Primers / Q000235:genetics; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D005854:Germ Cells / Q000528:radiation effects*; D016014:Linear Models; D016133:Polymerase Chain Reaction
D017931:DNA Primers