Efficient production of transgenic goat (Capra hircus) embryos using dual markers

The objective of this study was to develop an effective method to screen transgenic donor cells and improve the production efficiency of transgenic embryos. In the study, goat (Capra ibex) skin fibroblasts were co-transfected with two expression constructs, one containing the human α1 (I) procollagen cDNA fragment (4.3 kb) and the neomycin resistance (Neor) gene, and the second containing the green fluorescent protein (GFP) gene. The Neor and GFP genes were used as markers for the screening of donor cells. Results revealed a significant difference (P < 0.01) in the production rate of positive transgenic blastocysts (44.6% versus 82.8%) between donor fibroblasts selected using antibiotic G418 alone (Treatment A) and those from donor fibroblasts selected using antibiotic G418 and GFP (Treatment B), respectively. No significant differences were found between Treatments A and B in the total somatic cell nuclear transfer (SCNT) embryo cleavage rates (71.1% versus 65.9%) and total SCNT blastocyst formation rates (18.2% versus 15.7%). The research results indicate the Neor and GFP genes located at different constructs can be effectively combined by co-transfection to screen transgenic donor fibroblasts, and increase the yield of transgenic SCNT embryos carrying human α1 (I) procollagen cDNA in goats.