You might think that it would take genetic engineering — or some Frankenstein-style cutting and pasting — to give a worm the head and brain of another species. You'd be wrong.
Scientists at Tufts tweaked the cellular signals of flatworms to accomplish just that, according to a study published Tuesday in International Journal of Molecular Sciences. The scientists, led by Tufts professor Michael Levin and student Maya Emmons-Bell, cut off the heads of some Girardia dorotocephala, worms known to regenerate with ease. Then they interrupted the electrical pathways that cells inside the worms use to communicate, enabling the new heads to grow into shapes sported by other worms. Brains followed, taking on the morphology of related worms instead of that seen in Girardia dorotocephala. It's clear that genes aren't everything. In humans, environmental factors can change the way the same genes are expressed. In flatworms, it seems, nongenomic changes can even be manipulated to change brain and body shape.
The scientists hope the research can help them learn how to fix birth defects, or even how to make lost body tissues regenerate.