An Assessment of Androgenic/Anti-androgenic Effects of GH Transgenic Carp by Hershberger Assay

Objective To evaluate the androgenic and anti-androgenic effects of GH （growth hormone） transgenic carp in male rats.Methods Hershberger assay was carried out in castrated male SD rats aged 4-5 weeks.Testosterone propionate （TP） （0.4 mg/kg BW） was administrated for a positive control,GH transgenic carp （3.0 g/kg BW）＋TP （0.4 mg/kg BW）,parental carp （3.0 g/kg BW） ＋ TP （0.4 mg/kg BW）,and flutamide （Flu） （3.0 g/kg BW） were used for negative controls,and vehicle was administered orally for a blank control.All groups were administrated for 10 consecutive days.At the end of the test,animals were anesthetized,then weights of accessory sex organ were measured.Serum testosterone （T）,luteinizing hormone （LH）,and Follicle-Stimulating Hormone （FSH） levels were detected.Results The weights ratios of the accessory sex organs and body weights showed no significant differences between the solvent control and the GH transgenic carp-treated groups.Serum concentrations of FSH,LH,and T of the rats treated with GH transgenic carp ＋ TP showed no significant changes,compared with those treated with TP only.Conclusion GH transgenic carp does not have any androgenic agonist or antagonist properties in vivo screening tests.

First Pilot Studies on Transgenic Carp Completed at CAS

After the examination and approval by a nine-member panel headed by two members of CAS (The Chinese Academy of Sciences) and one member of CAE (The Chinese Academy of Engineering), successful pilot test on the cultivation of a new strain of transgenic Yellow River carp was announced on October 17 at the Wuhan-based CAS Institute of Hydrobiology. Scientists believe the success would lay a solid foundation for the industrialization of

Characterization of transgene integration pattern in F4 hGH-transgenic common carp (Cyprinus carpio L.)

The integration pattern and adjacent host sequences of the inserted pMThGH-transgene in the F4 hGH-transgeniccommon carp were extensively studied. Here we show that each F4 transgenic fish contained about 200 copies of thepMThGH-transgene and the transgenes were integrated into the host genome generally with concatemers in a head-to-tail arrangement at 4-5 insertion sites. By using a method of plasmid rescue, four hundred copies of transgenes fromtwo individuals of F4 transgenic fish, A and B, were recovered and clarified into 6 classes. All classes of recoveredtransgenes contained either complete or partial pMThGH sequences. The class I, which comprised 83% and 84.5%respectively of the recovered transgene copies from fish A and B, had maintained the original configuration, indicatingthat most transgenes were faithfully inherited during the four generations of reproduction. The other five classes weredifferent from the original configuration in both molecular weight and restriction map, indicating that a few transgeneshad undergone mutation, rearrangement or deletion during integration and germline transmission. In the five types ofaberrant transgenes, three flanking sequences of the host genome were analyzed. These sequences were common carpβ-actin gene, common carp DNA sequences homologous to mouse phosphoglycerate kinase-1 and human epidermalkeratin 14, respectively.

cGH Gene Transfer and PCR Detection in Crucian Carp

By inserting the CMV with HSV TK promoter into the plasmid pBlue-cGH which contained cGH gene, a chimeric expression vector was constructed for transgenic fish. After the vector was transferred into fertilized eggs of crucian carp by means of microinjection, the transgenic crucian carp was obtained. The result of PCR detection showed that the growth hormone gene of the exogenous carp was integrated into the genome of crucian carp, and the transgenic crucian carp displayed enhancement of its growth.