Emerging And Future Frontiers In Biotechnology

RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is a conserved biological response to double-stranded RNA that mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes. **Statement 1 is correct.** RNAi is a powerful tool for developing gene-silencing therapies. It allows researchers to target specific genes and reduce their expression, which can be beneficial in treating various diseases. **Statement 2 is also correct.** RNAi is being actively explored for cancer therapy. By targeting genes involved in cancer cell growth and proliferation, RNAi has the potential to be a novel approach for cancer treatment. **Statement 3 is incorrect.** RNAi is not typically used in developing hormone replacement therapies. Hormone replacement therapies introduce hormones into the body, while RNAi focuses on silencing gene expression within cells. **Statement 4 is correct.** RNAi can be used to develop crop plants resistant to viral pathogens. By introducing specific RNA molecules that target the virus, plants can be made more resistant to viral infections, improving agricultural yields.

Pronuclear transfer, in the context of human reproductive technology, is used for preventing mitochondrial diseases in offspring. Here's why - **Mitochondria:** These are cellular organelles with their own DNA (mitochondrial DNA or mtDNA) separate from nuclear DNA. Mutations in mtDNA can cause various inherited mitochondrial diseases that can affect organs like muscles, nerves, and the brain. - **Pronuclear Transfer Technique:** This technique involves the fertilization of an egg with sperm. Then, the pronuclei (nuclei before fusion) from both sperm and egg are removed. These pronuclei are then injected into a donor egg that has had its own pronuclei removed, but has healthy mtDNA.

**Statement 1 is correct.** Mitochondrial replacement therapy (MRT) is a reproductive technique used to prevent the transmission of mitochondrial diseases from mother to child. It involves replacing defective mitochondria in an egg or embryo with healthy mitochondria from a donor. MRT can be performed either before or after in vitro fertilization to ensure that the resulting embryo does not inherit mitochondrial diseases. **Statement 2 is correct.** Mitochondrial DNA (mtDNA), which is responsible for encoding genes essential for mitochondrial function, is inherited exclusively from the mother. Therefore, mitochondrial diseases caused by mutations in mtDNA are passed down maternally, and a child cannot inherit mitochondrial diseases from the father. Therefore, both statements are correct.

**Statement 1 is incorrect:** Covishield, produced by the Serum Institute of India, is a viral vector vaccine. It uses a weakened chimpanzee adenovirus vector to carry genetic material from the SARS-CoV-2 virus into human cells. **Statement 2 is correct:** Sputnik V is a vector-based vaccine, similar to Covishield. It uses two different human adenovirus vectors to deliver genetic material coding for SARS-CoV-2 spike proteins. **Statement 3 is correct:** COVAXIN, developed by Bharat Biotech, is an inactivated virus vaccine. This means the SARS-CoV-2 virus used in the vaccine is inactivated (killed) so it cannot cause infection, but it still triggers an immune response.

Coal gasification is a process that converts coal into syngas (a mixture of carbon monoxide, hydrogen, carbon dioxide, and water vapor). Syngas acts as a fundamental building block for the chemical industry. **I is correct:** Syngas can be converted into Ethanol through various chemical pathways, including catalytic synthesis or fermentation. **II is incorrect:** Nitroglycerine is produced through the nitration of glycerol. Glycerol is typically obtained from natural fats/oils or as a byproduct of biodiesel production, not from coal gasification. **III is correct:** Coal gasification is a major source of hydrogen for producing Ammonia. This ammonia is then reacted with carbon dioxide (also a product of gasification) to produce Urea.