Naturally occurring 'GM' butterflies have wasp genes

GM butterfly
CC BY 2.0 Sid Mosdell/Flickr

Mother Nature, not Monsanto, appears to be behind this striking twist.

Things are getting freaky in the critter world. Researchers from Spain and France have discovered genes from parasitic wasps present in the genomes of many butterflies. The results of their study reveal that even the iconic monarch contains naturally produced GMOs.

Say what?!

It all seems to have started with the particular habits of parasitic braconid wasps. These guys (well, females actually) lay their eggs inside caterpillars and inject a “giant virus” named bracovirus to trip up the caterpillars' immune response. Proving once and for all that truth really is stranger than fiction, this nifty trick allows the virus to integrate into the DNA of the caterpillars and control caterpillar development, allowing the wasp larvae overlords to colonize their host.

The bracovirus genes were found in the genomes of several species of butterfly and moth in addition to monarchs, including silkworms and pests such as the Fall Armyworm (Spodoptera frugiperda) and the Beet Armyworm (Spodoptera exigua).

And the genes found within are not just remnants, it appears that in fact, they play a protective role against other viruses known as baculoviruses. In addition, remarkably, the genes weren’t exclusive to the wasp virus, some of them originated from the actual wasp. In the armyworm species of moths, the researchers found genes that are closely related to genes from hymenoptera, including the honey bee.

Proponents of producing GM insects might latch on to this as an argument in favor of their work – that GM insects already exist in nature, so it’s a natural thing to do. But in showing fluidity of genes between species, the study really provides more ammunition for those opposed. For example, if insecticide resistance genes were to be artificially introduced into wasp species for biological control of other pests, it could lead to accidental transmission of this resistance to the target pests. And then what? I know, let's not try it and see what happens.

On MNN: 8 of the cutest toxic caterpillars

Tags: GMO | Insects | Nature


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