Scientist Have Discovered Ways to Prevent Mosquitoes From Reproducing
 |
| Genetically Modified Mosquitoes |
A ground breaking discovery has been made with the design of the first ever genetically modified mosquitoes to enhance the fight against mosquito borne diseases.
Genetically modifying mosquitoes to prevent disease may sound like science fiction, but the technology has advanced in recent years to the point where it is now applicable.
Scientists at The Imperial College, London completely blocked the reproductive ability of the Anopheles gambiae mosquito species, which spreads malaria, eliminating the lab population within 7 to 11 generations using a technique called gene drive.
This they did by planting a deadly self limiting gene in mosquito DNA, and engineering it such that the modification would spread through each generation faster than nature had intended, the London team figured they could completely crash a population with just a few genetically modified trojan skeeters. This concept “gene drive” is over a decades old, but no one had successfully concocted one in a lab, let alone applied it to a global public health scourge.
For the first time, scientists have elaborately demonstrated that a controversial new kind of genetic engineering can rapidly spread a self-destructive genetic modification.
“This is the first time we’ve shown that we can, in principle, manipulate the fate of an entire species,” says Crisanti, whose groundbreaking work has been supported in large part by the Bill and Melinda Gates Foundation, the world’s leading funder of gene drive technologies.
"This breakthrough shows that gene drive can work, providing hope in the fight against a disease that has plagued mankind for centuries,” said Professor Andrea Crisanti, the lead researcher from the Department of Life Sciences at Imperial College, London.
However, Crisanti went on to say that, “There is still more work to be done, both in terms of testing the technology in larger lab-based studies and working with affected countries to assess the feasibility of such an intervention.”
Malaria is a life threatening disease and is caused by a parasite called plasmodium and transmitted through the bite of infected female anopheles mosquito. Malaria is the biggest cause of preterm labour and killer of children under the ages of 5 in Africa, Asia and some parts of South America.
Mosquitoes are some of the most deadly creatures on the planet. Some species can carry and transmit viruses, bacteria and parasites through bites, infecting some 700 million people and causing more than 1 million fatalities each year.
 |
| Self limiting gene in mosquito |
This self limiting technology have stopped malaria spreading mosquitoes from reproducing via genetic modification, of course at the experimental level thereby paving the way to their eventual elimination in the wild.
This is coming after a team in Burkina Faso became the first in Africa to receive permission to release some 10,000 sterile male mosquitoes into the wild. This release will have no effect on malaria transmission, but will establish how modified mosquitoes interact with the natural population. Burkina Faso is a country at the front line of the war against the disease. Last year there were 9.8m cases of malaria, resulting in almost 4,000 deaths.
This is the first step in the programme to dramatically reduce the mosquito population in the country, and hopefully beyond. The initial release of the mosquitoes will enable researchers to gather more data about the longevity and dispersal of the insects, as well as how they interact with the natural insect population.
This technology is a major step towards eradicating malaria-carrying mosquitoes in the wild, by spreading female infertility.
The scientists targeted the double-sex gene, which determines the mosquito's sex, through a technique called gene drive. The technique spreads a gene, or particular suite of genes, through a population via reproduction.
Males who carried the genetic modification saw no changes, and neither did females with only one copy of the gene. But females with two copies showed both male and female characteristics, failed to bite and did not lay any eggs.
Previous attempts to suppress the mosquito population through gene drives have been unsuccessful because the insects have developed mutations which are resistant to the genetic modifications.
These mutations have then been passed onto offspring, preventing the reduction of the mosquito population.
But the scientists have targeted the double-sex gene because it is highly “conserved”, meaning that random mutations are lethal to the organism and would not be passed on. In the lab-based experiments, the gene drive saw the genetic modifications transmitted nearly 100 per cent of the time.
The researchers also said that additional experiments are required to investigate the efficacy and stability of the gene drive in conditions were necessary. This includes testing in more realistic settings, such as conditions mimicking tropical environments, and among larger mosquito populations.
Currently, control of these diseases is mostly limited to broad-spectrum insecticide sprays, which can harm both humans and non-target animals and insects.
The age long traditional methods of prevention is still in use, If you can prevent mosquito breeding, you can ward off an disease infestation. The first step is getting rid of their breeding grounds. There are hundreds of different species of mosquitoes, but every species has one thing in common – they all breed in standing water. The old adage that "an ounce of prevention is worth a pound of cure" rings true when it comes to stopping mosquito infestations.
What if there was a way to control these devastating diseases without the environmental problems of widespread insecticide use?
Don’t worry, these genetic changes only affect the mosquitoes: they are not transmitted to people when the mosquito bites for blood meal.
Post a Comment