Question

UPSC Prelims 2019 Question:

What is the Cas9 protein that is often mentioned in the news?

1. A molecular scissors used in targeted gene editing
2. A biosensor used in the accurate detection of pathogens in patients
3. A gene that makes plants pest-resistant
4. A herbicidal substance synthesized in genetically modified crops

Answer (Detailed Solution Below)

Option 1: A molecular scissors used in targeted gene editing

Detailed Solution

Explanation:

CRISPR-Cas9 is a unique technology that enables geneticists to edit parts of the genome. Genome editing (also called gene editing) is a group of technologies that give scientists the ability to change an organism's DNA. These technologies allow genetic material to be added, removed, or altered at particular locations in the genome.
CRISPR-Cas9 has a lot of potential as a tool for treating a range of medical conditions that have a genetic component, including cancer, hepatitis B or even high cholesterol.

Therefore, option (1) is the correct answer.

Subject: Science & Technology | Health and Diseases

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