X0508 4 2026-01-15 0001661998 Q32 Bio Inc. QTTB 0001682126 Lundberg Sven Ante Q32 BIO INC. 830 WINTER STREET WALTHAM MA 02451 true false false false false Stock Option (Right to Buy) 3.60 2026-01-15 4 A false 20363 2.75 A 2036-01-14 Common Stock 20363 20363 D This option was granted to the Reporting Person, a director of the Issuer pursuant to the 2024 Stock Option and Incentive Plan and pursuant to the Issuer's non-employee director compensation policy. This option shall vest in four equal quarterly installments as of the last date of each calendar quarter subject to the Reporting Person's continued service through such date and represents the Reporting Person's election to receive stock options in lieu of cash retainer fees. Due to administrative oversight this option award initially was not reported. /s/ Eric Bell, Attorney-in-Fact 2026-01-30