"Genetic Slaves" (遺伝子の奴隷, Idenshi no Dorei) is chapter 700+7 of the Naruto Gaiden mini-series.
Shin assures Sakura that as his "children" are actually his clones, they're expendable. Sakura disapproves of this, comparing him to Orochimaru, prompting Shin to divulge his former role a test subject for Orochimaru's cloning experiments. Naruto fails to sense Sakura's chakra and discusses with Sasuke the possibility of Shin being connected with Orochimaru due to the similarities between his Sharingan-filled arm and Danzō's. They decide to pay Orochimaru a visit and take Sarada and Chōchō with them, so they're better protected. Chōchō tries to dispel the heavy atmosphere by offering chips. Shin explains to Sakura his philosophy about life, death and evolution, which she criticises. Naruto and Sasuke meet up with Yamato outside of Orochimaru's hideout, who stays outside in order to pursue Orochimaru should something go wrong. Sasuke leads the way inside, and the group encounters Jūgo and Suigetsu, who Sarada recognises from her father's photo. They're all joined by Orochimaru. Sasuke questions him about Shin, and Orochimaru tells him of Shin's admiration of Itachi, as well as his usefulness as a cloning test subject. On a way to another room, Sarada pulls Suigetsu aside and asks him about Karin, learning she's in another hideout. Naruto notices their absence. Surprised about Sarada's predicament, Suigetsu aids her in running a DNA test with a sample retrieved from Karin's belongings and a cheek swab from Sarada. The test is a match, and Suigetsu declares Karin to be Sarada's mother. Naruto listens from around the wall. Suigetsu leaves as Sarada begins crying and is berated by Naruto on his way out. Naruto approaches Sarada, telling her they have to rescue Sakura, but she snaps at him with her Sharingan activated, accusing him and everyone else of lying to her her entire life, as well as denouncing any relation to Sakura.