OSAKA -- Scientists at Riken, the Japanese institute behind claims of an ingeniously novel method of creating stem cells, have been unable to duplicate the process despite multiple attempts, sources said Tuesday.
The struggle to verify the results of research published by Haruko Obokata and colleagues earlier this year casts further doubt on the existence of stimulus-triggered acquisition of pluripotency, or STAP, the phenomenon they described. Exposing ordinary body cells to various stresses had made them pluripotent, or able to differentiate into any type of tissue, the authors had claimed.