Game changer as mice pass down edited genes

New age: Scientists hope to use the technology to study human diseases in mice.

Gene drive technology could be the key to eradicating animal-spread diseases. Now, scientists have successfully used it in mammals for the first time. But could it spell ecological disaster?

For the first time, scientists have successfully altered mice using controversial gene-editing technology that could one day be used to wipe out entire species.

Gene drive technology breaks the natural rules of inheritance, ensuring that specific genes are passed down. As a result, selected characteristics can spread through a population rapidly.

In this breakthrough case, the first of its kind in mammals, scientists in California used the CRISPR tool to change a gene controlling hair colour in mice. When the edited mice bred with other mice in the laboratory, the babies born were far more likely to have grey hair rather than white.

But the technology could have more radical uses. The goal of many gene drive scientists is to wipe out malaria by stopping infected mosquitoes from reproducing. Malaria kills half a million people every year, mostly children younger than five, making it one of the most deadly diseases in human history.

Last year, scientists genetically edited infectious mosquitoes to make them infertile. Within 10 generations, all the female mosquitoes in the laboratory could not reproduce. The population was completely wiped out.

“Here we are with a technology that could radically change public health for the whole world,” said evolutionary biologist James Bull at the time.

Thousands of genetically modified mosquitoes will be released in Burkina Faso later this year, in the first ever real-world test of gene drive technology.

However, environmental groups fear that gene driving could spiral out of control. Once the animals are released, their spread could be impossible to control, with potentially devastating consequences for the food chain and the environment.

The United Nations (UN) debated a ban on releasing organisms that carry gene drives, but the plans were rejected by a number of countries that support biotechnology.

The latest breakthrough in mice will be welcomed in New Zealand, where authorities are considering using gene drives to wipe out invasive predators. Rats, possums and similar species have driven 42% of the country’s bird species to extinction and threatened its iconic flightless kiwi.

Ratting out

Hundreds of millions of lives were saved with the eradication of Smallpox in 1979, now we have the chance to do the same for malaria, dengue fever, Zika and more. And not just that, gene driving could help end hunger by wiping out pests that destroy crops.

However, environmental activists say the technology is dangerous and uncontainable. Ecological systems are delicately balanced. Removing one species from the food chain could have disastrous unintended consequences, not just for that region, but for the entire world.

You Decide

  1. Should gene drive technology be banned?
  2. Is it wrong to experiment on animals?

Activities

  1. What species would you get rid of and why? In groups, discuss this and choose an animal. Then give a short speech to the class stating your case.
  2. Read the article “The promise and peril of gene drives” in Become An Expert. Write a response to this statement: “Gene drive technology will greatly benefit humanity.”

Some People Say...

“If changing our world is playing God, it is just one more way in which God made us in his image.”

Aubrey de Grey

What do you think?

Q & A

What do we know?
For the first time ever, scientists have successfully used gene drive technology in mammals. They edited a dark hair colour gene in mice, which was inherited by subsequent generations. Researcher Kimberly Cooper, who led the study in California, says the technology will be used to develop genes in mice that mimic human diseases like cancer for medical research.
What do we not know?
Whether gene drive technology will ever be used widely to wipe out invasive and infectious species. Although the UN’s proposed ban was rejected, the international organisation committed to being cautious with the technology. We also don’t know exactly what effect the technology could have on the environment. Small changes could end up causing large unintended consequences.

Word Watch

CRISPR
A technology that allows researchers to easily edit genes. Before CRISPR was invented, genetic experimentation was far more difficult and expensive.
Burkina Faso
A country in West Africa with a population of 19 million. Up to 10,000 sterile male mosquitoes will be released.
Biotechnology
An area of science that uses living organisms to create chemicals or products. Biotech is usually used in agriculture (farming), food science and medicine.
New Zealand
The country has a very unique ecosystem that developed independently. Around 800 years ago, the only land mammals there were bats.
Rats
Last year, Doug Morris, a pest controller in Auckland, said some residents were too scared to go outside because of the number of rats.
Smallpox
An extremely contagious and deadly fever. It was eradicated thanks to global vaccinations.