expert corner
Yes, to GM Mosquito, No to GM Mustard: The
political understanding of a scientific issue
The genetically modified (GM) mosquito imported from China to eliminate Dengue
might not face the similar kind of opposition that the GM Mustard is facing in India, due
to double standards towards same technology, write Dr Bhagirath Choudhary and
Dr Anil Chauhan
Politics is a strange thing and
during election time, the
strangeness factor is more
pronounced. Add science to this
and it makes for a potent mix.
While mosquitoes have for the
past many years been doing their
seasonal job, spreading dengue
and chikungunya in India and
zika elsewhere, geneticists have
worked at modifying the same
mosquitoes genetically to stop
them from multiplying.
The technology is conceptually
simple. A gene is inserted into
male Aedes aegypti mosquitoes
that transmit the viruses causing
dengue, chikungunya and zika
fever. This gene produces a
protein that can “switch off” the
activity of other genes key to the
insect’s survival. Adult males
carrying the self-destruct gene
are, then, released in large
numbers in endemic localities to
mate with normal female Aedes
aegypti mosquitoes and produce
offspring that cannot survive
beyond larval stage. It is
important to note that the lethal
gene here is expressed only in the
offspring. The adult male is fed an
antidote — the antibiotic
tetracycline — to prevent the selfdestruct mechanism from
operating, so as to ensure its own
survival and mating with female
mosquitoes. In a matter of weeks,
the mosquito population drops
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BioVoiceNews | October 2016
drastically, as the offspring
inheriting the gene without the
antidote die.
The above genetically modified
(GM) mosquito route to control
dengue or zika has been approved
in countries from Brazil and the
US to Cayman Islands and
Panama. Trials have also been
happening in China, Australia and
Indonesia on infecting male
Aedes aegypti mosquitoes with
naturally-occurring Wolbachia
bacteria and releasing these into
the environment for copulating
with females in areas where
dengue is endemic.
Politicians – including in India –
have been pretty receptive to GM
technologies for control of dengue
and chikungunya. In October
2015, the Aam Aadmi Party (AAP)
government in Delhi sent a team
led by the vice chairman of its
Dialogue and Development
Commission, Ashish Khetan, to
southern China’s Guangzhou
province to study the latter’s
“success” in rooting out dengue
through mating of GM male
mosquitoes with female carriers
of the vector-borne disease. The
commission also allowed GBIT,
the Indian partner of Oxford
Insect Technologies — the UKbased developer of the
earlier-mentioned self-destruct
gene technology for controlling
Aedes aegypti mosquito
populations — to make a detailed
presentation during a dengue
vector control meeting on April 7
this year.
Such political support for GM
mosquitoes is not surprising for a
country that reported nearly one
lakh cases of dengue and
chikungunya with 200 deaths in
2015. This year, over 3,000
people in Delhi alone were