Board Thread:Naruto Discussions/@comment-1783334-20150430232848/@comment-1783334-20150501061437

NeedleJizo wrote: Probably because the face replica isn't laughing like a derp.

In the anime it's not really clear, but manga-wise the resemblance is there, in some panels more than others. Especially when it was first seen on Danzo's arm and Madara's chest, when the emphasis was on the fact that they had Hashirama's cells. We also see Hashirama's serious and calm side so the laughing like the derp argument is invalid.