ASSIGNMENT#8:

Essay #4—Gene Editing

Genome editing is a method that lets scientists change the DNA of many organisms,
including plants, bacteria, and animals.

And it is now possible to edit the human genome. Genome editing technologies enable
scientists to make changes to DNA, leading to changes in physical traits, like eye color,
and disease risk. Scientists use different technologies to do this. These technologies act
like scissors, cutting the DNA at a specific spot. Then scientists can remove, add, or
replace the DNA where it was cut.

The first genome editing technologies were developed in the late 1900s. More recently,
a new genome editing tool called CRISPR, invented in 2009, has made it easier than
ever to edit DNA. CRISPR is simpler, faster, cheaper, and more accurate than older
genome editing methods. Many scientists who perform genome editing now use
CRISPR.

One way that scientists use genome editing is to investigate different diseases that
affect humans. They edit the genomes of animals, like mice and zebrafish, because
animals have many of the same ​genes

(Links to an external site.)

as humans. For example, mice and humans share about 85 percent of their genes! By
changing a single gene or multiple genes in a mouse, scientists can observe how these
changes affect the mouse’s health and predict how similar changes in human genomes
might affect human health.

Scientists are developing ​gene therapies

(Links to an external site.)

—treatments involving genome editing—to prevent and treat diseases in humans.
Genome editing tools have the potential to help treat diseases with a genomic basis,
like cystic fibrosis and diabetes. There are two different categories of gene therapies:
germline therapy and somatic therapy. Germline therapies change DNA in reproductive
cells (like sperm and eggs). Changes to the DNA of reproductive cells are passed down
from generation to generation. Somatic therapies, on the other hand, target
non-reproductive cells, and changes made in these cells affect only the person who
receives the gene therapy.

https://www.genome.gov/genetics-glossary/Gene?id=70

https://www.genome.gov/genetics-glossary/Gene?id=70

https://www.genome.gov/genetics-glossary/Gene-Therapy?id=77

https://www.genome.gov/genetics-glossary/Gene-Therapy?id=77

In 2015, scientists ​successfully used

(Links to an external site.)

somatic gene therapy when a one-year old in the United Kingdom named Layla
received a gene editing treatment to help her fight leukemia, a type of cancer. These
scientists did not use CRISPR to treat Layla, and instead used another genome editing
technology called TALENs. Doctors tried many treatments before this, but none of them
seemed to work, so scientists received special permission to treat Layla using gene
therapy. This therapy saved Layla’s life. However, treatments like the one that Layla
received are still experimental because the scientific community and policymakers still
have to address technical barriers and ethical concerns surrounding genome editing.

Technical Barriers

Even though CRISPR improved upon older genome editing technologies, it is not
perfect. For example, sometimes genome editing tools cut in the wrong spot. Scientists
are not yet sure how these errors might affect patients. Assessing the safety of gene
therapies and improving upon genome editing technologies are critical steps to ensure
that this technology is ready for use in patients.

Ethical Concerns

Scientists and all of us should carefully consider the many ethical concerns that can
emerge with genome editing, including safety. First and foremost, genome editing must
be safe before it is used to treat patients. Some other ethical questions that scientists
and society must consider are:

1. Is it okay to use gene therapy on an embryo when it is impossible to get
permission from the embryo for treatment? Is getting permission from the
parents enough?

2. What if gene therapies are too expensive and only wealthy people can
access and afford them? That could worsen existing health inequalities
between the rich and poor.

3. Will some people use genome editing for traits not important for health, such
as athletic ability or height? Is that okay?

4. Should scientists ever be able to edit germline cells? Edits in the germline
would be passed down through generations.

Your Assignment:

What is your position on the editing of human genes? Remember that this is a class in
rhetoric, so you MUST identify as many of the arguments, both pro and con, as possible
and explain what those arguments are and, to the extent possible, why those who hold

https://www.theguardian.com/science/2015/nov/05/baby-girl-is-first-in-the-world-to-be-treated-with-designer-immune-cells

https://www.theguardian.com/science/2015/nov/05/baby-girl-is-first-in-the-world-to-be-treated-with-designer-immune-cells

those positions believe as they do. Then, and only then, may you state and support your
position on this topic.

TARGET LENGTH: 300 to 500 words

DUE DATE: February 28, 2021