Question 27 from UPSC CSE 2020 - S&T

Question

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?

Accepted Answer

Correct Option: D. 1, 2, and 3

Strategy: The strategy identifies that all three statements concern frontier biotechnologies. Statement 1 describes germline gene editing, which is scientifically possible but ethically debated. Statement 2 addresses embryonic stage editing, a basis for potential gene therapies under active research. Statement 3 involves human stem cell integration into animal embryos, a concept explored in chimeric studies. Since each statement reflects feasible applications or research in genetics and stem cell science, there is no scientific basis to doubt any individual claim, thus supporting option D.

Key Info: ## Key Biotechnologies Overview

**Germline Gene Editing**
This technique alters the DNA of reproductive cells (sperm or eggs) or early embryos, leading to changes that are inheritable by future generations. While scientifically feasible and experimentally performed using methods like CRISPR-Cas9, it remains highly controversial and restricted in many countries due to significant ethical concerns.

**Embryonic Stage Genome Editing**
This involves modifying an embryo's genetic makeup before tissue differentiation. It offers potential for preventing inherited diseases but also raises serious ethical and safety issues. Interventions of this type have been attempted in human embryos under laboratory conditions.

**Human-Animal Chimeras (using iPSCs)**
Human induced pluripotent stem cells (iPSCs) are adult cells reprogrammed to differentiate into various cell types. Injecting iPSCs into animal embryos, such as pig embryos, creates human-animal chimeras. This process is studied to gain insights into human development, model diseases, and advance organ transplantation research. Chimeric studies have shown partial integration of human cells into animal embryos, with the ultimate goal of advancing regenerative medicine.

**Relevant Global Debates**
Discussions surrounding these technologies include:
- Bioethics
- Policies on inheritable genetic modification
- Advances in regenerative biotechnology

Answer

Option A: 1 only

Answer

Option B: 2 and 3 only

Answer

Option C: 2 only