Using the pronuclear injection technique, what is the average percentage of offspring carrying the transgene?

Using the pronuclear injection technique, what is the average percentage of offspring carrying the transgene?

• A. 5%
• B. 20%
• C. 50%
• D. 80%

Answer: (B)

Pronuclear injection places the transgene directly into a fertilized egg so it can integrate into the genome. Because this integration is random and not all injected embryos survive or acquire the transgene, only a portion of the offspring end up carrying it. In typical experiments, about one-fifth of the live-born offspring are transgenic, roughly 20%. This reflects the practical efficiency and the mosaic nature of early integration. If you later breed a confirmed transgenic founder to a non-transgenic partner, about half of the progeny would inherit the transgene, assuming stable germline transmission.

Pronuclear injection places the transgene directly into a fertilized egg so it can integrate into the genome. Because this integration is random and not all injected embryos survive or acquire the transgene, only a portion of the offspring end up carrying it. In typical experiments, about one-fifth of the live-born offspring are transgenic, roughly 20%. This reflects the practical efficiency and the mosaic nature of early integration. If you later breed a confirmed transgenic founder to a non-transgenic partner, about half of the progeny would inherit the transgene, assuming stable germline transmission.