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?

Answer: D. All three statements about advances in human genetic technology are correct. Statement 1 is CORRECT. GERMLINE GENETIC EDITING refers to introducing genetic changes in REPRODUCTIVE CELLS (oogonia, spermatogonia, primordial germ cells) of a prospective parent. Such edits would be heritable, passing to all subsequent generations. Techniques like CRISPR-Cas9 can in principle modify germline cells in vitro. This raises profound ethical concerns and is currently banned or restricted in most jurisdictions for clinical use (although laboratory research is permitted in some countries). Germline editing remains technically feasible and the focus of ethical debate. Statement 2 is CORRECT. EMBRYONIC GENE EDITING involves modifying the genome of an EARLY-STAGE EMBRYO (zygote, blastocyst stage). This is what Chinese scientist HE JIANKUI controversially did in 2018, when he reported editing the CCR5 gene in IVF embryos to confer HIV resistance, leading to the birth of twin girls. The international scientific community widely condemned the experiment as unethical and premature. He was sentenced to three years in prison. Technically, embryonic editing using CRISPR is well-established in laboratory settings; clinical application remains tightly restricted. Statement 3 is CORRECT. HUMAN INDUCED PLURIPOTENT STEM CELLS (iPSCs), generated by reprogramming adult somatic cells back to a pluripotent state (Yamanaka factors, 2006), can be INJECTED INTO ANIMAL EMBRYOS to study development and produce CHIMERAS. Research teams led by Juan Carlos Izpisua Belmonte (Salk Institute) reported in 2017 the creation of HUMAN-PIG CHIMERIC EMBRYOS using this technique, aiming to grow human organs (kidney, pancreas, heart) inside pigs for transplantation. The chimeric embryos were not brought to term but the demonstration is technically valid. Similar work in rats and pigs continues, with significant scientific and ethical scrutiny. So all three statements describe technologies that exist in current human reproductive biology research. Source: NCERT Class 12 Biology 'Biotechnology and its Applications'; Nature publications on CRISPR germline editing and on iPSC-derived interspecies chimeras; WHO and UNESCO frameworks on human genome editing.