12.Gene Therapy

Question 1

What is gene therapy?

Answer 1

Gene therapy is a technique that involves modifying the genome of a human by either removing a faulty gene or replacing it with a new gene to treat a disease.

Question 2

Who conducted the first experiment of gene therapy and what disease was treated?

Answer 2

Dr. French Anderson conducted the first experiment of gene therapy in 1990. He successfully treated SCID or bubble boy syndrome.

Question 3

What are the two types of gene therapy based on cell type?

Answer 3

*Somatic Cell Gene Therapy
*Germ Cell Gene Therapy

Question 4

What is the difference between somatic cell gene therapy and germ cell gene therapy?

Answer 4

*Somatic Cell Gene Therapy: Genes are replaced or removed in body cells. The effects are limited to the individual and not passed on to the next generation.
*Germ Cell Gene Therapy: Genes are replaced or removed in reproductive cells such as sperm, ovum, or zygote. This therapy can potentially treat future generations, but it is controversial and banned worldwide due to high risks and low success rates.

Question 5

What is knockdown gene therapy?

Answer 5

Knockdown gene therapy involves silencing a faulty gene. It is also known as gene silencing and can be achieved through techniques like RNA interference and antisense technology.

Question 6

What is knockout gene therapy?

Answer 6

Knockout gene therapy involves removing a faulty gene. It is also known as gene removal or gene termination and can be achieved through techniques like CRISPR Cas-9 and Transcription Activator-like Effector Nucleases (TALENs).

Question 7

What is SCID, and why is it called the “bubble boy syndrome”?

Answer 7

SCID is a disease in which the immune system collapses. It is called the “bubble boy syndrome” because affected individuals are kept in a sterile environment, resembling a bubble, to protect them from infections.

Question 8

What is CRISPR Cas-9?

Answer 8

CRISPR Cas-9 is a genome editing tool used for modifying DNA.

Question 9

What does CRISPR stand for?

Answer 9

CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats.

Question 10

What is the function of Cas-9 in CRISPR Cas-9?

Answer 10

Cas-9 is a CRISPR-associated protein-9 and acts as a restriction endonuclease enzyme in the CRISPR Cas-9 system.

Question 11

What is g-RNA?

Answer 11

g-RNA stands for guide RNA, which is a component of the CRISPR Cas-9 system and acts as a guide for targeting specific DNA sequences.

Question 12

How does CRISPR Cas-9 work?

Answer 12

CRISPR Cas-9 works by using guide RNA (g-RNA) to target specific DNA sequences and the Cas-9 protein to cut and modify the DNA at those targeted locations.

Question 13

What is the role of g-RNA in CRISPR Cas-9?

Answer 13

The g-RNA carries a complementary sequence to the targeted DNA and guides the Cas-9 protein to the specific location for DNA cleavage.

Question 14

How does the Cas-9 protein cleave the DNA?

Answer 14

The Cas-9 protein binds to the targeted DNA sequence along with the g-RNA and cleaves both DNA strands, leading to a double-stranded break.

Question 15

Why is it called guide RNA?

Answer 15

The g-RNA is referred to as guide RNA because it carries the instructions (address) for targeting specific DNA sequences and delivering the Cas-9 protein to those locations.

Question 16

When was CRISPR Cas-9 first discovered in bacteria?

Answer 16

CRISPR Cas-9 was first discovered in bacteria in 1986-87.

Question 17

When was CRISPR Cas-9 used for human genome editing for the first time?

Answer 17

CRISPR Cas-9 was used for human genome editing for the first time in 2012.

Question 18

What was the significance of CRISPR Cas-9 according to the journal Science?

Answer 18

According to the journal Science, CRISPR Cas-9 was the biggest scientific achievement of the decade.

Question 19

How can the genetic sequence of g-RNA be modified in CRISPR Cas-9?

Answer 19

The genetic sequence of g-RNA can be modified to target specific faulty genes in the human genome for removal.

Question 20

What is one major benefit of CRISPR Cas-9?

Answer 20

One major benefit of CRISPR Cas-9 is its accuracy, which provides a significant boost to gene therapy.

Question 21

Give an example of a medical application of CRISPR Cas-9.

Answer 21

In 2017, American doctors used CRISPR Cas-9 to edit the genome of an embryo for the treatment of Hypertrophic Cardiomyopathy, a heart disease characterized by thickening of the heart muscles.

Question 22

What was the controversial experiment involving CRISPR Cas-9 conducted by a Chinese scientist in 2018?

Answer 22

In 2018, a Chinese scientist modified the genome of an embryo using CRISPR Cas-9 to make it HIV-resistant, resulting in the birth of twin babies. This experiment was heavily criticized worldwide.

Question 23

Apart from human genome editing, in what other areas can CRISPR Cas-9 be used?

Answer 23

CRISPR Cas-9 can be used for genome editing in crop plants for the development of genetically modified (GM) crops.

Question 24

What is the recent application of CRISPR Cas-9 in relation to COVID-19?

Answer 24

Recently, a COVID-19 test kit based on CRISPR Cas-9 has been developed by Sherlock Bioscience, a US-based company.

Question 25

Name one potential application of CRISPR Cas-9 discussed by scientists.

Answer 25

Some scientists believe that CRISPR Cas-9 could be used as a tool to achieve immunity against viral diseases like COVID-19 or HIV.

Question 26

What are two issues related to CRISPR Cas-9 mentioned in the text?

Answer 26

Two issues related to CRISPR Cas-9 mentioned are the promotion of the idea of a designer body and concerns about cost accessibility, as it may only be available to wealthy individuals.