Aside from Frankenstein, previous attempts to make synthetic life have focused on genes. Geneticist Craig Venter and his colleagues, for example, announced in 2010 that they had created a one-celled creature by inserting an artificial genome in an existing cell that reproduced.
Now a separate team of scientists from Harvard University and the California Institute of Technology have built an eight-armed jellyfish by inserting muscle cells from a rat into a sheet of silicone.