Not so unthinkable after all! Scientists create ‘virgin birth’ in female fruit flies by modifying just THREE genes – so could it be done in humans too?
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Babies born to women without men may have moved one step closer after scientists created virgin births from fruit flies.
The first recorded case of a virgin birth in a crocodile earlier this year made headlines around the world – with crocodiles joining a host of animals, including chickens, turkeys and Komodo dragons, which can give birth without a male partner, to produce offspring. with only their own DNA.
Now scientists have taken a species of fruit fly that naturally cannot have a virgin birth and caused it by modifying copies of just three genes.
The discovery of these key genes in the six-year study helps to understand the phenomenon of virgin births in the natural world, and may bring scientists one small step closer to understanding how it might happen in humans.
But virgin births in humans or any type of mammal that they’ve never naturally had in the wild is a much trickier proposition because there are many other complicated processes involved.
Playing God: Scientists have taken a species of fruit fly that cannot naturally be born virgin and made it happen by modifying copies of just three genes
How did they do? This image explains how researchers achieved their “virgin births” feat
The new study, importantly, yielded two generations of fruit flies that were born without a father, which is not believed to have been achieved in similar attempts in mice.
Dr. Alexis Sperling, lead author of the historic fruit fly study, from the University of Cambridge, said: ‘People are fascinated with virgin births, largely because of the story of Jesus – this story has been around for 2,000 years for a reason.
“The new results provide important insight into the causes of virgin births, and I would never say that this could never be possible for humans, but this is not a direction a scientist should want to take, and we don’t know enough, or have regulations that would allow it to happen at any time in the foreseeable future.”
Dr. Herman Wijnen, associate professor of biological sciences at the University of Southampton, said: ‘The genes that were manipulated in the fruit fly are genes that are shared with humans, but there are substantial differences between early development in flies and humans.’
Last year, scientists reported that they had managed to achieve a virgin birth in mice, but it took hundreds of attempts to create three mice pups that survived to adulthood.
When the fruit flies in the current study had their eggs examined, 16 percent were successful virgin births that grew into embryos, and 1.4 percent became adult fruit flies.
The fruit flies in the current study were manipulated to have virgin births of their own.
Mouse studies usually required a second female mouse to give birth to the first mouse’s virgin offspring or to provide biological material.
The new study, published in the journal Current Biology, looked at 44 genes that may play a role in natural virgin births in Hawaiian and Brazilian fruit flies.
They were able to narrow these down to three key genes, then modify the similar genes within a related type of fruit fly that does not naturally have virgin births.
Dr. Alexis Sperling (pictured), lead author of the landmark fruit fly study, from the University of Cambridge, said: ‘People are fascinated with virgin births, largely because of the story of Jesus’
Future: dr. Sperling (left, with her student Rosie) said the research would provide “important insight into the causes of virgin births”
The researchers first bred these flies to have one less copy of a gene called Desat2, which may allow a virgin female to save extra copies of her own DNA for her offspring, rather than throwing them away to replace them with the DNA of a father.
They then used genetic engineering to give fruit flies two extra copies of a gene that controls a protein called Polo.
Polo appears to play a role normally occupied by sperm in starting the process in the nucleus that allows eggs to develop into offspring.
Finally, the fruit flies got an extra copy of a gene called Myc, which probably speeds up cell division, so the many biological complications of a virgin having her own offspring can’t slow down the process of conception.
In the wild, and often in zoos, female animals can be given virgin birth if they live in isolation, with no hope of a mate, to increase their chances of survival.
But there is some evidence that insect pests plaguing gardeners’ and farmers’ tomato plants may also be evolving to have virgin births, as pesticides prevent them from mating normally.
The new findings in the future could provide insight into how to block the process and protect the country’s greenhouses.
WHAT IS CRISPR CAS9?
Crispr-Cas9 is a tool for making precise edits to DNA, discovered in bacteria.
The abbreviation stands for Clustered Regularly Inter-Spaced Palindromic Repeats.
The technique involves a DNA-cutting enzyme and a small tag that tells the enzyme where to cut.
The CRISPR/Cas9 technique uses tags that identify the location of the mutation and an enzyme, which acts like tiny scissors, to cut DNA at a precise location, allowing small parts of a gene to be removed
By editing this tag, scientists can target the enzyme to specific parts of the DNA and make precise cuts wherever they want.
It has been used to ‘silence’ genes – effectively turning them off.
When cellular machinery repairs the DNA break, a small piece of DNA is removed.
This allows researchers to precisely switch off specific genes in the genome.
The approach has previously been used to edit the HBB gene responsible for a condition called β-thalassemia.