Board Thread:Theories and Speculation/@comment-1512913-20150520114510/@comment-2120712-20150520162229

They were mostly like modified with Hashirama DNA when Madara took the cells he had on him and integrated it into the Demonic statue. My guess is that being turned into a White Zetsu changes one genetic structure and makes it more open to changes. The White Zetsu went through two Hashi modifications: 1) From when Madara cultivated a non-sentient clone of Hashi. Being they were hooked up to the statue themselves(as know was due to how Infinite Tsu keeps its victuals alive by having statue acts a life support system while changing their very being aka Zetsu) they took were modified as a result. 2) Upgrade from Yamato's dna (we know that Kabuto did this upgrading).

Blank slate dna + 2 Hashi dna infusions.