Question

What are some major confounds of generating transgenic mice via pronuclei injection?

1) Off-target effects
2) Low efficiency of transgene integration
3) Mosaic expression of transgene
4) All of the above

Answer 1

When generating transgenic mice via pronuclei injection, major confounds include off-target effects, low efficiency of transgene integration, and mosaic expression of the transgene.

Step-by-step explanation:

When generating transgenic mice via pronuclei injection, there are several major confounds to consider:

1. Off-target effects: The injected transgene may integrate into unintended regions of the genome, leading to unintended gene expression. This can result in unpredictable phenotypic effects.
2. Low efficiency of transgene integration: Not all injected transgenes will successfully integrate into the mouse genome. This can result in low rates of successful transgenic mouse generation, requiring multiple injection attempts.
3. Mosaic expression of transgene: Even if a transgene successfully integrates, it may not be uniformly expressed in all cells of the resulting mouse. This can lead to inconsistent phenotypic effects and difficulties in studying the transgene's function.

Therefore, the correct answer is: 4) All of the above.