Cloning

• Cloning describes a number of different
processes that can be used to produce
genetically identical copies of a biological
entity.
• Clones are organisms that are exact
genetic copies. Every single bit of their
DNA is identical.
• Human Identical Twins are clones of each
other.

• Collectively refers to processes used to
create copies of DNA fragments.
• Animal cloning has been the su-bject of
scientific experiments for years, but
garnered little attention until the birth of
the first cloned mammal in 1996, a sheep
named Dolly.

• Since Dolly, several scientists have cloned other
animals, including cows and mice.
• No human cloning attempts have been made
because there have been many disadvantages
that involve the cloning of both humans and
animals.

CLONING
Artificial
Embryo
Twinning
Reproductive
cloning
THERAPUETIC
CLONING
Natural
Cloning

• Natural Cloning
• In nature, twins form very early in development
when the embryo splits in two. Twinning
happens in the first days after egg and sperm
join, while the embryo is made of just a small
number of unspecialized cells. Each half of the
embryo continues dividing on its own, ultimately
developing into separate, complete individuals.
Since they developed from the same fertilized
egg, the resulting individuals are genetically
identical.

• Artificial Embryo Twinning
• Artificial embryo twinning is a relatively low-tech way to
make clones. As the name suggests, this technique mimics
the natural process that creates identical twins.
• Artificial embryo twinning uses the same approach, but
it is carried out in a Petri dish instead of inside the
mother. A very early embryo is separated into individual
cells, which are allowed to divide and develop for a short
time in the Petri dish. The embryos are then placed into a
surrogate mother, where they finish developing. Again,
since all the embryos came from the same fertilized egg,
they are genetically identical.

• Reproductive cloning
• Somatic Cell Nuclear Transfer
• Somatic cell nuclear transfer (SCNT), also
called nuclear transfer, uses a different
approach than artificial embryo twinning, but
it produces the same result: an exact genetic
copy, or clone, of an individual. This was the
method used to create Dolly the Sheep.

• What does SCNT mean? Let's take it apart
• Somatic cell
• A somatic cell is any cell in the body other
than sperm and egg, the two types of
reproductive cells. Reproductive cells are also
called germ cells. In mammals, every somatic
cell has two complete sets of chromosomes,
whereas the germ cells have only one
complete set.

• Nuclear:
• The nucleus is a compartment that holds the cell's DNA.
The DNA is divided into packages called chromosomes,
and it contains all the information needed to form an
organism. It's small differences in our DNA that make each
of us unique.
• Transfer:
• Isolate a somatic cell from an adult female Next they
remove the nucleus and all of its DNA from an egg cell.
Then we transfer the nucleus from the somatic cell to
the egg cell. After a couple of chemical tweaks, the egg
cell, with its new nucleus, will behave just like a freshly
fertilized egg. It is developed into an embryo, which was
implanted into a surrogate mother and carried to term.

• THERAPUETIC CLONING
• you may have heard about researchers cloning, or
identifying, genes that are responsible for various
medical conditions or traits. What's the difference?
• When scientists clone an organism, they are
making an exact genetic copy of the whole
organism.
• When scientists clone a gene, they isolate and
make exact copies of just one of an organism's
genes. Cloning a gene usually involves copying the
DNA sequence of that gene into a smaller, more
easily manipulated piece of DNA, such as a
plasmid. This process makes it easier to study the
function of the individual gene in the laboratory.

• There will be an endless supply of animals
to clone, and we will never run out of food
from animals.
• The animal in which we intend to clone
will result perfectly the same as the
animal which has been cloned in every
way, the eyes, the nose, the ears, the
face, everything provided the environment
is same.

• Chance of curing certain diseases and
being able to breed ideal stock for
research and consumption.
• Cloning a extinct species to bring them
back, to clone organs to repair damaged
organs in people, and variety of other
medical advancements

• Disadvantages of cloning is the cost,
the technology being used for less
than honorable ways, and the
controversy that surrounds cloning.
• Losing gene diversity is another of
the disadvantages of cloning.
DISADVANTAGES OF CLONING

• Another of the disadvantages of cloning is
that there are a lot of ethical
considerations that would cause most
people to protest. One of these ethical
concerns is that cloning is unnatural, and
considered “playing GOD.”
• Because of the risk taking involved in
cloning, it is a technology that many
experts say may be better left alone, at
least until it is better understood.
DISADVANTAGES OF CLONING

• United Kingdom:
• On January 14, 2001 the British
government passed The Human
Fertilisation and Embryology (Research
Purposes)
• Regulations 2001 to amend the Human
Fertilisation and Embryology Act by
permitting to research around
• stem cells and cell nuclear
replacment,thus allowing therapeutic
cloning.
LEGAL ISSUES

• United Nations:
• On December 13, 2001, the United Nations General
Assembly began elaborating an international
convention against the reproductive cloning of
humans,A broad coalition of States, including
Spain, Italy, the Philippines, the United States,
Costa Rica and the Holy See sought to extend the
debate to ban all forms of human cloning, noting
that, in their view, therapeutic human cloning
violates human dignity.
• In March 2005 a non-binding United Nations
Declaration on Human Cloning, calling for the ban
of all forms of Human Cloning contrary to human
dignity, was adopted.
LEGAL ISSUES

• United States
• In 1998, 2001, 2004 and 2007, the United States
House of Representatives voted whether to ban all
human cloning, both reproductive and therapeutic.
• On March 10, 2010 a bill was introduced with a
section banning federal funding for human cloning.
• Such a law, if passed would not prevent research
from occurring in private institutions (such as
universities) that have both private and federal
funding.
• There are currently no federal laws in the United
States which ban cloning completely, and any such
laws would raise difficult Constitutional questions
similar to the issues raised by abortion.
LEGAL ISSUES

• INDIA
• The Department of Biotechnology of the
Ministry of Science and Technology has
adopted ethical policies on the human
genome,
• which have laid down inter alia India’s
position on cloning. The text, “Ethical Policies
on the Human Genome,
• Genetic Research and Services,” states that,
“as a principle, human cloning shall not be
permitted.”
LEGAL ISSUES

• Lenon’s Tooth:
• Here is a story for your "truth is stranger than fiction"
files: a Canadian dentist paid approximately $31,000 in
2011 for a tooth extracted from the late John Lennon.
Dr. Michael Zuk recently announced that he has sent
the tooth to a U.S. laboratory in hopes of having DNA
extracted and sequenced. His ultimate goal is to have
John Lennon cloned. Dr.Zuk has outlined his plans on
a website.
• It is unclear whether any DNA that is of sufficient
quality for sequencing remains in the tooth. The tooth
was rotten when it was removed in the 1960s. Lennon
gave the tooth to his housekeeper at the time, and her
son eventually put it up for auction.
• The media has covered the story as an amusing piece of
news. However, the articles have failed to cover the
two main ethical issues raised by the story. Firstly, is
John Lennon's privacy (and the privacy of his
descendants), violated by the DNA sequencing effort?
• The first ethical reason would be that John Lennon's
two sons share his genetic information and would
potentially be affected if the sequence is ever released
publically.
CASE STUDIES 1

• Lenon’s Tooth
• The second ethical concern raised by Dr.Zuk's efforts is whether
human cloning is acceptable. Based on his statements, Dr.Zuk
has undertaken this project in hopes of "bringing back" a musical
legend that died tragically before his time. To be clear, if John
Lennon were successfully cloned, the new John Lennon would
NOT be the same man we are all familiar with. The clone would
share DNA with the original but would not share any of the life
experiences that shaped his persona. Many human traits, both
physical and behavioral, are influenced to varying degrees by
the environment. As a comparison, identical twins are genetic
clones but typically differ in appearance, behavior, and the
diseases that affect them. This is particularly apparent in older
twins after years of different environmental influences.
• You may be surprised that the U.S. does NOT have any federal
laws banning human cloning!! YAY! We might just have another
John-the-legend-wait-for-it-dary-lenon ;) :D
CASE STUDIES 1

• DOLLY THE SHEEP
• Dolly the sheep, as the first mammal to be cloned from an adult
cell, is by far the world's most famous cloneIn 1996, cloning was
revolutionized when Ian Wilmut and his colleagues at the
Roslin- Institute in Edinburgh, Scotland.
• To produce Dolly, scientists used an mammary gland cell from a
six-year-old Finn Dorset white sheep. They had to find a way to
'reprogram' the mammary cells - to keep them alive but stop
them growing – which they achieved by altering the growth
medium (the ‘soup’ in which the cells were kept alive). Then
they injected the cell into an unfertilised egg cell which had
had its nucleus removed, and made the cells fuse by using
electrical pulses. The unfertilised egg cell came from a Scottish
Blackface ewe. When the research team had managed to fuse
the nucleus from the adult white sheep cell with the egg cell
from the black-faced sheep, they needed to make sure that the
resulting cell would develop into an embryo. They cultured it
for six or seven days to see if it divided and developed
normally, before implanting it into a surrogate mother, another
Scottish Blackface ewe. Dolly had a white face.
CASE STUDIES 2

• DOLLY THE SHEEP
• From 277 cell fusions, 29 early embryos developed and were
implanted into 13 surrogate mothers. But only one pregnancy
went to full term, and the 6.6 kg Finn Dorset lamb 6LLS (alias
Dolly) was born after 148 days.
CASE STUDIES 2

• What happened to Dolly?
• Dolly lived a pampered existence at the Roslin Institute. She
mated and produced normal offspring in the normal way,
showing that such cloned animals can reproduce. Born on 5 July
1996, she was euthanased on 14 February 2003, aged six and a
half. Sheep can live to age 11 or 12, but Dolly suffered
from arthritis in a hind leg joint and from sheep pulmonary
adenomatosis, a virus-induced lung tumour that is common
among sheep which are raised indoors.
• The DNA in the nucleus is wrapped up into chromosomes, which
shorten each time the cell replicates. This meant that Dolly’s
chromosomes were a little shorter than those of other sheep her
age and her early ageing may reflect that she was raised from
the nucleus of a 6-year old sheep. Dolly was also not entirely
identical to her genetic mother because the mitochondria, were
inherited from Dolly’s egg donor mother.
CASE STUDIES 2

• Why clone sheep?
• Dolly the sheep was produced at the Roslin Institute
as part of research into producing medicines in the
milk of farm animals. Researchers have managed to
transfer human genes that produce useful proteins
into sheep and cows, so that they can produce, for
instance, the blood clotting agent factor IX to treat
haemophilia or alpha-1-antitrypsin to treat cystic
fibrosis and other lung conditions.
CASE STUDIES 2

• Since Dolly
• Since 1996, when Dolly was born, other sheep have been
cloned from adult cells, as have cats, rabbits, horses and
donkeys, pigs, goats and cattle. In 2004 a mouse was
cloned using a nucleus from an olfactory neuron, showing
that the donor nucleus can come from a tissue of the body
that does not normally divide.
• Improvements in the technique have meant that the
cloning of animals is becoming cheaper and more reliable.
• The advances made through cloning animals have led to a
potential new therapy to prevent mitochondrial diseases
in humans being passed from mother to child. About 1 in
6000 people is born with faulty mitochondria, which can
result in diseases like muscular dystrophy. To prevent
this, genetic material from the embryo is extracted and
placed in an egg cell donated by another woman, which
contains functioning mitochondria. This is the same
process as used in cloning of embryonic cells of animals.
CASE STUDIES 2

• JUST IMAGINE !!
• Human cloning technology could be used to reverse heart attacks.
Scientists believe that they may be able to treat heart attack
victims by cloning their healthy heart cells and injecting them
into the areas of the heart that have been damaged.
• Infertility - infertile couples can have children
• Down's syndrome - those women at high risk for Down's syndrome
can avoid that risk by cloning
• Leukemia - we should be able to clone the bone marrow for
children and adults suffering from leukemia. This is expected to
be one of the first benefits to come from cloning technology.
• Cancer - we may learn how to switch cells on and off through
cloning and thus be able to cure cancer
Potential Benefits of Human Cloning

• Do you approve of human cloning ?
• Do you approve cloning of other animals ?
• Do you think it’s right to harvest organs and
tissue from clones ?
• If you had the option,would you want to clone
yourself ? Why ?
• Do you think the benefits outweigh the risks
with cloning humans ?

Cloning

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