X0609 4 2026-08-25 0001661998 Q32 Bio Inc. QTTB 0002016144 Violette Shelia M. false Q32 BIO INC. 830 WINTER STREET WALTHAM MA 02451 false true false false Chief Scientific Officer false Common Stock 2026-08-25 4 S false 2798 16.56 D 127771 D Common Stock 36277 I By Violette Holdings LLC Represents shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units. These sales were automatic and not in the discretion of the Reporting Person. Shares held by Violette Holdings LLC ("Violette Holdings"). The Reporting Person is a manager of Violette Holdings and disclaims beneficial ownership of these shares except to the extent of her pecuniary interest therein, if any, and this report shall not be deemed an admission that she is the beneficial owner of such shares for purposes of Section 16 of the Exchange Act or for any other purpose. /s/ Eric Bell, Attorney-in-Fact 2026-08-27