DNA modification or

What is CRISPR Technology?

CRISPR is an acronym: Clustered Regularly Interspaced Short Palindromic Repeats

This is a mouthful so we shorten it by saying, formally, CRISPR-Cas9

How it Works

3 Main Components:

Guide RNA - RNA that is used to locate the targeted gene

Cas9 - "molecular scissors" used to cut undesired DNA at a specific location

DNA - the desired piece of DNA which is finally inserted in place of mutated DNA

Video Explaining how CRISPR works:

Possible Applications

Disease Treatment - Monogenic diseases (diseases caused by a mutation in a single gene) can potentially be cured with the use of CRISPR technology. Possible diseases include sickle cell disease and beta-thalassemia.

Food and Agriculture - Gene editing can make farming significantly more efficient. CRISPR is utilized to edit a crop's genetics to select for desirable traits. As a result, it can create more resilient crops, impervious to droughts and other environmental impacts.

Animal Related Research - CRISPR technology applied to farm animals may serve to improve productive genetic traits, improve various animal products, create increased resistance to diseases or to minimize the environmental impact on farming.

Why is Crispr the Best Options for these Applications?

It is cheaper, quicker, and more accurate than other forms of DNA Modification
The genome can be directly edited: Specific sequences can be targeted
Being versatile and simple, any part of DNA can be edited using the "snipping tool"
Crispr can help to treat many serious illnesses that we face today: Hepatitis B, high cholesterol, cancer, etc.

How Crispr-Cas9 Works: In Detail

Main Component: Enzyme

Enzymes are biological catalysts that help a reaction to take place. In Crispr, Cas9 is the enzyme that acts as the "snipping tool" to the DNA sequence. A specific location is chosen, and the two strands of DNA are cut at this specific location. After Cas9 cuts the DNA, more DNA can be added at this location, or DNA can be removed.

RNA

A strand of RNA, called Guide RNA, is about 20 bases long. After binding to the DNA, this developed sequence is what guides Cas9 to the part of the sequence that needs editing. Cas9 can then cut at the correct position. In this 20 base long gRNA, the bases compliment the bases of the target DNA sequence. What this means is that the gRNA can really only has the ability to bind to one part of the DNA sequence, making the target sequence easier to find.

What Exactly is Happening?

Essentially, a mutation is being made in the DNA. A mutation is changing the gene that may result in a different form of DNA. Base units can be altered of shifted to cause a mutation, or sections can be moved or deleted.

Case Studies

Mosquitos

Malaria

Although Malaria is not as prevalent in the United States, it is still an epidemic in many impoverished countries. Often with flu-like symptoms such as vomiting, fever, and chills, Malaria could easily be mistaken for another illness and therefore ignored until it grows in intensity.
The vector for malaria is mosquitoes, that reproduce rapidly and are virtually everywhere. Since they can reproduce in very small puddles of water, it is almost impossible to eliminate everywhere that mosquitoes can reproduce.

Previous methods of stopping malaria have proved to be ineffective. For example, bed nets and indoor spraying are widely used since they are cheap, but they do not eradicate the illness from an area.

How Crispr Technology Can Be Used to Stop Malaria

A lethal mutation would be added into the DNA of a mosquito. As this mosquito goes on to reproduce, the lethal mutation will be spread and eventually, all of the mosquitoes would die. This would take away the malaria vector and virtually rid the world of a disease that kills more people each year than sharks, snakes, and bears combined. As malaria continues to harm much of the work, Crispr may eventually become a viable option to stopping the spread of this horrible disease.

Arctic Apple

What is the Arctic Apple?

A non-browning apple that does not bruise or rupture. This apple does not brown when cut open or when sitting on a supermarket shelf. When a normal apple is cut open, polyphenol oxidase and polyphenolics mix together to create the signature brown on the apple that many people do not desire.
There is no PPO (polyphenol oxidase) in an Arctic Apple, so there is little to no browning since there is no chemical reaction to cause it.

How Could Crispr Technology Be Used?

Although the apples are a product of GMOs, Crispr may now be used since it makes biotech plant breeding much cheaper and much more precise. Crispr would target the gene in the apple that produces the enzyme, PPO, that makes the apple brown. An extra strand of RNA is added in, and the gene is silenced. Gene silencing and gene editing are easily done by Crispr, making it the next step in the making of Arctic Apples.

Crispr Pigs

Double Muscle Pigs

With more muscle, these pigs have more meat to be harvested. Although these pigs are not approved for human consumption yet, they are not made like conventional GMO pigs that transfer genes from one species into another, so there are hopes that these pigs will be approved by regulators soon.
Double muscle pigs are thought to have the same benefits as double muscle cows: leaner meat and higher meat yield per animal.

How Could Crispr Technology Be Used?

A single gene in the pig's DNA is knocked out using a biotech tool, such as Crispr. Myostatin is what inhibits muscular growth, so this gene is knocked out in order to ensure the "double muscle."

Ethical Concerns

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