Consider the following statements:
(1) Genetic changes can be introduced in the cells that produce eggs or sperms of a prospective parent.
(2) A person’s genome can be edited before birth at the early embryonic stage.
(3) Human induced pluripotent stem cells can be injected into the embryo of a pig.
Which of the statements given above is/are correct?
The pre-implantation embryo stage is generally not favoured for genome editing as it would most likely lead to a mosaic individual and possibly to more unforeseen detrimental effects. Various studies in different animal models have demonstrated the feasibility of gene editing in animals at the zygote stage. Hence, statements 1 and 2 are correct. The researchers implanted more than 2000 human-pig chimeric embryos into 41 surrogate sows, resulting in 18 pregnancies and 186 embryos a month later. However, many of the embryos were much smaller than normal and seemed to grow more slowly, the group reports today in Cell. Hence, so far there has not been success in growing human organs in pigs. But this experiment shows that human induced pluripotent cells can be injected into pigs embryo. Hence statement 3 is also correct. Therefore, the correct answer is (d).