BUTTERFLY WINGS ‘REPAINTED’ USING GENE EDITING
Butterfly wings have been given a new look by researchers who used the gene-editing tool CRISPR to alter the colours and patterns of their distinctive markings.
The international team based at the Smithsonian Tropical Research Institute in Panama focused their attention on the WntA gene – a gene known to strongly influence the staggering diversity of shapes and colours found in butterfly wing patterns in nature. They discovered that by ‘rewiring’ this gene using the DNA-snipping tool CRISPR, they were able to customise the wing markings of seven different butterfly species.
“Imagine a paint-by-numbers image of a butterfly,” said researcher Owen McMillan. “The instructions for colouring the wing are written in the genetic code. By deleting some of the instructions, we can infer which part says ‘paint the number 2s red’ or ‘paint the number 1s black’. Of course, it’s really a lot more complicated than this, because what is actually changing are networks of genes that have a cascading effect on pattern and colour.”
The team hopes that the findings will eventually help them to learn more about how the colourful insects evolved.
“The butterflies and moths, or Lepidoptera, are the third largest group of organisms known on the planet,” said Dr Arnaud Martin. “Once we have identified the sets of genes that are regulated by a gene like WntA, we can look at the sequence of different butterflies in the family tree to see when and where these changes took place during the 60 million years of butterfly evolution.”
A normal Heliconius sara butterfly is shown on the left; the same species that has had its genes edited using CRISPR is shown on the right