Assume you have transfected embryonic stem cells with a gene-targeting vector containing the neomycin resistance gene as a positive selection marker and the thymidine kinase gene as a negative selection marker. You observe that some cells are resistant to neomycin but killed by ganciclovir. What was the outcome of gene targeting procedure?

Question

Quizplus · Accepted Answer

The presence of neomycin resistance indicates that the vector integrated into the genome, while sensitivity to ganciclovir suggests that the thymidine kinase gene is still present, indicating nonhomologous recombination.

Assume You Have Transfected Embryonic Stem Cells with a Gene-Targeting