Dolly the Sheep was the first — so what
are we cloning next?
By Scientific American, adapted by Newsela staff on 07.12.16
Word Count 552
Dolly the Sheep at the National Museums of Scotland, in Edinburgh, Scotland. Photo: Wikimedia Commons
Twenty years ago, on a beautiful day in the hills above Edinburgh, Scotland, two old
friends and co-workers named Ian Wilmut and Alan Trounson set off on a hike. High over
the city, Wilmut confided that he had a secret to share. Wilmut had helped to birth a lamb
in the lab. He did this not with a mother and father sheep, but from DNA taken from a
grown sheep. He successfully cloned a mammal.
“Crikey! I was stunned,” says Trounson, a stem cell biologist. He sat down on a nearby
stone. It was a warm day but Trounson felt a chill. “It changed everything,” he says.
Could We — Or Should We?
The discovery caused people to ask questions about whether humans could be cloned or
diseases could be cured.
The lamb, Dolly, was born on July 5, 1996. Today, 20 years later, the form of cloning used
with Dolly has largely faded from public memory.
In 2016, cloning a person remains unlikely. Scientists see no benefit to it. It carries an
unacceptable level of risk to the person being cloned, they say.
Some agricultural cloning is used in the U.S. and China. Many countries do not allow
cloning animals for food. One scientist in South Korea is charging $100,000 to clone pets.
Stem Cells Offer Possibilities
Cloning has advanced the study of stem cells. Scientists can clone adult cells to make
stem cells that can form a wide range of other cells. These cells can help replace cells in
people with diseases, or test medicines to make sure they're safe. They can even be used
to study cancer.
Dolly’s birth was huge for science. It proved that the nucleus, or central core of the adult
cell, had all the DNA necessary to give rise to another animal.
Is A Clone The Same As The Original?
Dolly died on Feb. 14, 2003, at age 6 from a lung infection. The infection is common
among animals who do not go outdoors. It probably had nothing to do with her being a
cloned animal.
Scientists think it is possible to clone a human. It does not mean they think that is a good
idea.
It is possible that people would pay for cloned cows, goats and pigs. In 2008, the U.S.
government decided there was no difference between cloned and non-cloned ones. It has
allowed cloning them, although mainly for breeding and not to eat. In China, a company
has plans to produce at least 100,0000 cloned beef cattle.
Science Fiction Suggestions
Cloning could possibly bring back endangered animals. There has even been talk of using
it to bring back woolly mammoths. Stem cell biologist Robin Lovell-Badge dismisses these
ideas as “fairly silly.”
The idea of cloning a loved one — human or pet — who has passed away has fallen out of
favor. This is in part because we have come to understand the part that environment plays
in determining who we become. The genetics might be the same, but would a clone still
be the same lovable pet or person you know? Lovell-Badge doesn't think so. He called the
idea of cloning a pet “stupid.”
What about the idea of cloning a person? Lovell-Badge likes the idea even less.
“I have never thought of a good enough reason" to clone a human, he says.
Quiz
1
2
3
4
Which of the following are two main ideas from the article?
(A)
Cloning is a controversial issue; the majority of people feel it is not a good
idea.
(B)
A sheep was cloned 20 years ago; scientists are still figuring out how to use
cloning today.
(C)
One man's experiment with cloning a sheep was a success; scientists today
are still using his cloning method with animals.
(D)
Cloning has become a very popular practice in the science community;
people rely on it to hold onto loved ones.
Which detail would be most important to include in a summary of the article?
(A)
Dolly died on Feb. 14, 2003, at age 6 from a lung infection.
(B)
Cloning could possibly bring back endangered animals.
(C)
Many countries do not allow cloning animals for food.
(D)
Wilmut had helped to birth a lamb in the lab.
How is the structure in the introduction [paragraphs 1-2] diffferent from the structure in the
section "Stem Cells Offer Possibilities"?
(A)
The introduction has a question and answer structure whereas "Stem Cells
Offer Possibilities" has a sequence structure.
(B)
The introduction has a problem and solution structure whereas "Stem Cells
Offer Possibilities" has a compare and contrast structure.
(C)
The introduction has a narrative structure whereas "Stem Cells Offer
Possibilities" has a cause and effect structure.
(D)
The introduction has a main idea and detail structure structure whereas
"Stem Cells Offer Possibilities" has a description structure.
Which of the following elements is NOT used in the article?
(A)
direct quotes
(B)
opinions
(C)
statistical data
(D)
examples
Answer Key
1
2
3
4
Which of the following are two main ideas from the article?
(A)
Cloning is a controversial issue; the majority of people feel it is not a good
idea.
(B)
A sheep was cloned 20 years ago; scientists are still figuring out how to
use cloning today.
(C)
One man's experiment with cloning a sheep was a success; scientists today
are still using his cloning method with animals.
(D)
Cloning has become a very popular practice in the science community;
people rely on it to hold onto loved ones.
Which detail would be most important to include in a summary of the article?
(A)
Dolly died on Feb. 14, 2003, at age 6 from a lung infection.
(B)
Cloning could possibly bring back endangered animals.
(C)
Many countries do not allow cloning animals for food.
(D)
Wilmut had helped to birth a lamb in the lab.
How is the structure in the introduction [paragraphs 1-2] diffferent from the structure in the
section "Stem Cells Offer Possibilities"?
(A)
The introduction has a question and answer structure whereas "Stem Cells
Offer Possibilities" has a sequence structure.
(B)
The introduction has a problem and solution structure whereas "Stem Cells
Offer Possibilities" has a compare and contrast structure.
(C)
The introduction has a narrative structure whereas "Stem Cells Offer
Possibilities" has a cause and effect structure.
(D)
The introduction has a main idea and detail structure structure whereas
"Stem Cells Offer Possibilities" has a description structure.
Which of the following elements is NOT used in the article?
(A)
direct quotes
(B)
opinions
(C)
statistical data
(D)
examples