Correct Option (d)
All three statements are correct.
Explanation
- Statement 1: Genetic changes can be introduced into germline cells, which are the cells that produce eggs or sperms. Technologies such as CRISPR-Cas9 enable precise modifications to the DNA in these cells. Such changes, if implemented, would be heritable, meaning they could be passed down to offspring. This field is known as germline gene editing.
- Statement 2: Genome editing can be performed at the early embryonic stage. Research has demonstrated the ability to use gene-editing tools, like CRISPR, to modify the genome of human embryos in laboratory settings, often with the aim of correcting disease-causing genes. While technically feasible, the clinical application of human embryo genome editing is subject to significant ethical and regulatory debate.
- Statement 3: Human induced pluripotent stem cells (iPSCs) have the capacity to differentiate into various cell types. In scientific experiments, human iPSCs have been successfully injected into the embryos of other species, such as pigs, to create interspecies chimeras. This research aims to study early human development, model human diseases, or potentially grow human-compatible organs within animals for transplantation purposes.
Incorrect Options
- Option (a) is incorrect because statements 2 and 3 are also correct.
- Option (b) is incorrect because statement 1 is also correct.
- Option (c) is incorrect because statement 3 is also correct.