The alarming pace of discoveries
which garnered momentum with unraveling of structure of DNA (Deoxyribonucleic
acid) the basic blue print of living organisms in the year 1953 has transformed
Life Sciences. This phenomenal discovery besides cracking the fundamental unit
of inheritance (genes), ignited the latent curiosity of manipulation of genetic
material among scientists. Incidentally the collective efforts accelerated the
genesis of a gamut of molecular biology techniques culminating in the evolution
of new branch of study, Genetic Engineering which encompasses all the processes
aimed at altering the genetic code of an organism. Till 1970s, selective
breeding was widely practiced to manipulate genetic material. Initially, biomedical
techniques like artificial insemination, invitro fertilization (test-tube babies)
were included under genetic engineering. The discovery of restriction enzymes
in 1968, an indispensable tool for gene cloning accelerated the pace of genetic
engineering. Eventually genetic engineering invariably refers to gene cloning. Cloning refers to the process wherein a target
DNA (gene) is inserted into a circular piece of DNA or plasmid of a bacterium
and generation of hundreds of identical copies of gene. DNA cloning is used in
production of biopharmaceuticals, gene therapy and gene analysis. The term
cloning became immensely popular when scientists at University of Edinburgh
cloned the sheep Dolly in 1996.
In fact, Dolly had three mothers:
one provided DNA, another egg and the third one was a surrogate mother. Using
the technique of somatic cell nuclear technique (SCNT), nucleus from the
mammary gland is inserted into an unfertilized egg, whose nucleus was removed.
This hybrid cell was implanted in a surrogate mother. The success of Dolly
prompted scientists to use this technique for other animal species like dogs
and pigs. While cloned animals are widely hailed as symbols of scientific
excellence, the fear creating designer babies and an army of clones began to
haunt the scientific community.
On 24th January China
announced the creation two cloned monkeys Zhong Zhong, Hua Hua, the first
primate clones developed with a technique similar to one used in Dolly. To achieve
this humongous feat, scientists at Institute of Neurology (ION) Shanghai made
few modifications. They erased chemical modifications of DNA that potentially
turn the embryonic cell into a specialized cell. Similarly, they used DNA from
fetal cells and added few factors to turn on genes responsible for embryonic
development. They thus created 79 clone embryos and implanted them into 21
surrogate mothers and obtained two clones of long tailed monkeys, Macaca fasicularis. Cloning primates is
extremely arduous and has abysmally low success rate. Scientists across the World lauded their
Chinese counterparts on their outstanding achievement who unabashedly expressed
concerns that this technique might be used to clone humans. Besides humans the
subclass of primates (the big brained mammals) includes monkeys, apes, lemurs,
bushbabies and lorises. Allaying fears,
scientists at ION clarified that they have created the clones to study genetic
factors responsible for Alzheimer’s disease. By creating a population of
genetically identical monkeys’ scientists want to deactivate the genes
responsible for causing diseases individually and study its effect. Besides
there is huge demand for cloned monkeys to test drugs.
Primates have been preferred models
for studying human mental disorders and degenerative diseases. Hundreds of
monkeys are used to investigate Parkinson’s disease. Incidentally, genetic
closeness and similarity makes the study of primates significant and informative.
Genome sequencing revealed that humans are 96% similar to the apes. A section
of scientists believe that the latest development is highly significant since
SNCT technique can be used to save endangered animals.
Human cloning includes therapeutic
cloning and reproductive cloning. Therapeutic cloning involves cloning of human
cells or tissues for medical purposes like transplants while reproductive
cloning is about making an entire clone of a human being.
Amidst burgeoning reports of
production of various animal clones and rapid advancements in genetic
engineering international community contemplated the possibility of elaborating
a convention for addressing the concerns on human cloning. Accordingly, in 2005
UN General Assembly has adopted a declaration urging member states to prohibit
all forms of human cloning “in as much as
they are incompatible with human dignity and protection of human rights”. But
the declaration was toothless since it was non-binding and owing to the
ambiguity of wordings, countries failed to arrive at a consensus. Compelled by
the urgency to address the ethical concerns of cloning, countries began to urge
UN for a binding treaty for prohibiting human cloning. As of now, countries are
still divided with each country legislating its own laws. As of 2015, seventy
countries are reported to have banned human cloning. EU, Canada explicitly bans
human reproductive cloning. India doesn’t have specific law on cloning. It
allows therapeutic cloning and use of embryonic stem cells and issued
guidelines banning reproductive cloning. UK grants licenses to Universities for
carrying out research on diabetes, Parkinson’s and Alzheimer’s Disease and
permits research on human-animal hybrid embryos. As of now US promotes stem
cell research and development of pluripotent stem cell lines not involved in
creating a human embryo. Though there
are no federal laws banning human cloning completely, human reproductive
cloning is banned in fifteen states while three states prohibit use of federal
funds for the same.
With the development of primate
clones, human cloning seems to have moved away from the realms of science
fiction to a real possibility. Currently, certain sections of scientific
community fervently back therapeutic human cloning for its potential benefits
in organ transplanting. Similarly, childless heterosexual couples suffering
from genetic disorders are pitching for reproductive human cloning.
Human cloning while offering
promise of ameliorating genetic disorders like cystic fibrosis, Down disease,
Tay-Sach’s disease can enliven slew of fictional realities of designer babies
and genetic upgrades like smarter babies posing serious ethical concerns. It is
a tight rope walk. In absence of a binding international concerns, nations are
free to make their own legislations and issue guidelines to laboratories. Crux
of regulating human cloning lies in strict enforcement. In any case, scientists
must exercise discretion and shoulder the responsibility of defining their
research activities for the betterment of society.
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