How
it all Began
SRABONTI NARMEEN ALI
Ever wonder why people always compare certain traits you have to your parents or other people in your family? What exactly do people mean when they say that you have your mother's eyes or your father's nose? How exactly does the gene pool affect your life? The answers to all these questions came in the form of a discovery made fifty years ago. In April of 1953 James Watson and Francis Crick, both scientists at Cambridge, England, discovered the chemical structure for genes, Deoxyribonucleic Acid or DNA. They won the Nobel Prize in 1962 for their discovery. On October 6-13, British Council, Bangladesh commemorated the 50th year of Crick and Watson's discovery by holding an exhibition in Dhaka.
SCORES
of school children in white school uniforms laughed
out loud as a graduate student from Dhaka University
concluded her two and a half hour presentation on DNA
structure with “What do you think of that?", breaking
the ice with her informal tone. The student then invited
Professor Haseena Khan of Dhaka University to take the
audience on a tour around the Exhibition explaining
the basic advantages of DNA technology. The journey
proved to be quite fascinating.
DNA is a chemical structure that forms
chromosomes. It is a double helix structure, consisting
of two strands entwined around each other. Each strand
has a sequence of chemical “bases” or nucleotides These
bases: adenine, cytosine, guanine and thymine, are known
in coding language as A, C, G and T. The bases are paired
as such: A bonds with T and C bonds with GP Watson and
Crick discovered the actual structure of DNA with the
help of Rosalind Franklin and Maurice Wilkins. The four
scientists studied X-Ray reflections and found that
the structure was helical.
The discovery of DNA gave scientists
countless opportunities. There are many uses to DNA
technology, especially in the field of medical research.
DNA technology enables us to identify
people with samples taken from blood, hair or skin cells.
This is known as DNA “fingerprinting.” Everybody's DNA
chemical structure is the same, but a person can be
identified according to the sequence of their base pairs.
Scientists determine identity by studying the repeating
base patterns within the sample Although these patterns
cannot give an individual "fingerprint," they
can determine whether two DNA samples are from the same
person or a relation. The technique is also used to
help solve crimes. Genetic evidence identifies an individual,
determining whether they were at the scene of a crime
and providing evidence. Sir Alec Jeffreys of Leicester
University first derived this procedure in 1984 and
it was put to use in 1986 during a rape investigation
in Leicestershire, finding the rapist after testing
about four thousand men.
The DNA50 Exhibition, co-organised by
the Department of Genetic Engineering at Dhaka University,
was an idea passed on from the British Council in Malaysia.
An exhibition will also take place in Chittagong on
October 25-31.
“The
main objective is to develop a partnership between scientists
from the UK and Bangladesh,” says Laila Khaled, Culture
and Science Programme Officer at BC. “Also, we want
to incorporate and promote interest among the mass population.
Right now only the National Museum of Science and Technology
wanted to collaborate to help us raise awareness. We
think it is really important to educate and inform people
of what is going on especially if we can encourage students
to get into this field.”
The British Council held an inauguration
ceremony on October 6th in which Dr. Khandakar Mosharraf
Hossain, Minister of Health and Family Welfare was the
Chief Guest and Dr. David Carter, the British High Commissioner
to Bangladesh is the Special Guest. On the 7th and 8th,
apart from having a general public viewing of the exhibition,
Dhaka University's Department of Genetic Engineering
also prepared and gave a presentation “Celebrating the
miracle of the DNA molecules in our lives.” The British
Council organised Science Fairs for young students in
both Bangla and English Medium schools.
“We invited different schools, science
clubs, including one from Naraynganj, and just want
to raise awareness on scientific discoveries, inventions
and experiments,” says Khaled. “The students who have
shown the most interest and participated the most are
obviously the Dhaka University students from the Department
of Genetic Engineering and Biotechnology, because this
is their field and they understand it more than others,
but they have also put a lot of effort into making this
information more accessible to someone who is not very
knowledgeable in science or familiar with scientific
terms. We are just trying to provide information on
what DNA is -- just the basics.”
Genetic
engineering, however, has not been welcomed with open
arms from everybody. In February of 1997 for example,
when the genetically engineered sheep clone “Dolly”
was born, it brought on severe criticism from religious
and other groups who considered such cloning to be unethical.
In cloning, DNA from the somatic cells is taken and
the nucleus of the egg is sucked out and the extracted
DNA is injected into it. Electrical impulses are then
applied resulting in cell division eventually developing
into an embryo which is implanted into the uterus of
the mother. The problem lies in the fact that not enough
is known about this procedure.
Professors Ian Wilmut and Keith Campbell
of the Roslin Institude in Scotland conducted this “miracle
of science” by taking a mammary cell from Dolly's “mother,”
resulting in the two sheep being genetically identical.
Dolly was followed by the production of twenty-two mice,
seven of them being clones of an original clone in 1998
at the University of Hawaii.
Unfortunately the failure rate of this
kind of cloning is a shocking 97% with a high number
of deformed features. The process also causes the wastage
of hundreds of eggs and embryos, difficult pregnancies
and miscarriages. Cells in the clone may mutate, as
90% of the cells in our DNA are dormant with only 10%
active. In the case of Dolly it was found that the dormant
genes could become active. Such mutations could result
in a severely damaged clone. In December 2002 a little
known company called Clonaid announced the successful
birth of a cloned human causing an uproar all over the
world. Detractors of cloning pointed out that everything
that went wrong with Dolly could be applied to human
cloning and so was morally an unacceptable process.
The issue however, was soon forgotten as the media hype
died down when the company failed to produce the cloned
person in public citing 'security reasons'.
Scientists
and Pharmaceutical companies also experiment with DNA
to produce (among other things) "tailor-made medicines"
by a system called Pharming. The DNA is used so that
the medicine does not act as a cure but instead focuses
directly on the cause of the particular disorder. Scientists
are conducting research for a tailor made drug, Abacavir
which helps fight HIV/AIDS by interfering with viral
reproduction. They are also studying a gene that prevents
diseases such as asthma, heart disease, cancer and osteoarthritis.
DNA allows the drug to be delivered directly to the
area which has the problem A patient with cancer in
the liver can take medication that only affects the
liver. DNA technologies enable the drug to be delivered
directly to the liver without affecting the other parts
of the body. This is better known as the 'drug delivery
system'. “The initial notion is one gene, one disease,
one drug,” says Nadeem Ashraf, of Dhaka University's
Department of Genetic Engineering. “Genetic diseases
like Alzheimer's Disease, Huntington's Disease and Cancer
can be cured by studying alteration in DNA structure
of sequence that causes or gives rise to the disease.
If we can identify the genes responsible for the disease(s)
we will be able to find a cure eventually.”
One of the more immediate uses in DNA
technology is the research about the production of human
spare parts to be grown and replaced in human beings.
Aside from medical and scientific purposes,
however, DNA plays an important role in our everyday
lives in Bangladesh.
“DNA is the secret of life,” says Ashraf.
“It answers questions we have about hereditary traits,
mutilations, replications. DNA modification in particular
is something that will greatly affect Bangladesh. It
can affect all aspects of our life: medical, agricultural,
industrial, even with the smallest things that you take
for granted, like beverages.”
“DNA technology helps us prevent and
fix problems caused by or in industries. In the Hazaribagh
tanning industry for example, it is a complete mess
there. There is a bad stench everywhere, and the water
in nearby ponds are completely polluted. We find lots
of mutated fish, etc and need to treat them for their
mutations. What we do is that we degrade them biologically
and create micro-organisms to treat them. These micro-organisms
are made efficient for treating bi-products.”
Crops
in Bangladesh are vulnerable to a variety of problems
ranging from insects, fungi and viruses. The idea is
now to produce a plant that will be resistant to the
above by taking out the gene in the crop that is susceptible
to these outside factors and genetically modifying so
that the crop will be impervious to any kind of danger.
As a result, farmers do not have to use pesticide, which
is not only bad for the environment but also bad for
the farmers. Many farmers do not take necessary precautionary
measures when spraying pesti cide exposing both themselves
and the people around them to illness. Also, pesticide
is expensive and not all farmers can afford it. DNA
technology is also used to increase the yield population
in the environmental affects in coastal areas. Since
there is a high quantity of salt in the soil farmers
can only irrigate once a year. However, if a hybrid
is made of the crops, they can have two sets of crops
which in turn increases yield.
Another agricultural aspect that DNA
technology affects is the production of jute. “It is
very unfortunate that jute mills in Bangladesh were
closed and India's opened because it is one of our greatest
natural resources,” says Ashraf. “The thing about jute
is that it is cold sensitive -- meaning it is not cold
tolerant. Work is being done in Dhaka University to
genetically engineer jute in order for it to become
cold tolerant.”
However, there is controversy surrounding
the issue of DNA technology influencing and manipulating
agricultural growth. The process is as such: DNA strands
of a variety of agro-products are taken and crossed
with other products. There are social, ethical and religious
issues with this kind of modification that Bangladesh
still has to decide on. There are no laws determining
whether genetic modification is illegal, legal or needs
regulation. It is a difficult decision for companies
that are attempting to get into the field of DNA modification
for agro products. They cannot do much more than research
because if they start it and a law is implemented making
it illegal, these companies will have invested huge
amounts of money for nothing and will have to start
all over again, working around the laws.
As
is the case in every situation, the issue of DNA and
its effects on our society has its pros and cons. On
one hand we are dealing with a question of morality:
do we have a right to clone living beings, or even genetically
modify plants and crops? On the other hand we are dealing
with possible breakthroughs for scientific discoveries,
things that can save our lives. Many agonise over the
question: Are religion and science contradictory?
“I think that we need to break the stereotype
that science and religion conflict,” says Khaled. “Education
is really the only way to move past these stereotypes
and millstones. We feel that by exposing people to new
things, they will learn more, read more and discover
things on their own. We are not only raising awareness
about the advantages of DNA but we are also promoting
learning and education and knowledge. We believe that
knowledge is powerful.”
It
is to spread some of this power among young people that
British Council decided to hold this exhibition that
was different in its innovative style of imparting knowledge.
Through colourful videos, lively lectures and huge life-size
posters, children as well as interested adults were
given a unique tour into the world of DNA technology.
The idea was to make children aware of the importance
of this discovery that has changed the way we think
and live.
Milestones
in DNA Research
Students
may be familiar with three major landmarks of DNA researchdiscovery
of the double-helix structure, recombination techniques
for DNA, and now the deciphering of the human genome.
But students may not realize how young the field of
DNA research is, with the first milestone occurring
only 48 years ago.
1953James Watson and Francis Crick discover
the double-helix structure of DNA.
By the early 1950s, scientists had established
that DNA contains the genetic code that is passed from
generation to generation of living beings, but they
still did not know how the genetic information was passed
from parent to child. British scientist Rosalind Franklin
worked with X-rays of DNA to try to find a structural
pattern in DNA samples. When James Watson saw Franklin's
work, it gave him an important clue. Then he and Crick
combined their separate lines of research. They literally
built models of possible DNA structures until they came
up with the one that fit the data: a double helix.
1972Paul Berg and his co-workers create
the first recombinant DNA molecule.
While
studying isolated genes, Berg developed a method for
splitting DNA molecules at selected sites, attaching
segments of the molecule to the DNA of a virus, and
then introducing it into bacterial or animal cells.
The foreign DNA was incorporated by the host, which
then produced proteins not ordinarily found in the host.
This joining of two pieces of DNA from different species
is called recombinant DNA. The process is a cornerstone
of genetic engineering.
2001The Human Genome Project (HGP, a
government-backed group) publishes its working draft
in Nature magazine and Celeraa private company also
mapping the human genomepublishes its draft in Science.
The publication of the human genome
culminates over 10 years of research. One of the surprises
uncovered by the HGP and Celera is how few genes humans
actually have, something in the neighborhood of 35,000.
By comparison, an insect as simple as a fruit fly has
20,000 genes.
Scientists believe that the project
will enable them to develop a new approach to drugs
that target disease at the molecular level.
Source: The Internet
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