X0206 3 2018-06-20 0 0001681087 AVROBIO, Inc. AVRO 0001451612 Booth Bruce C/O AVROBIO, INC. 1 KENDALL SQUARE, BUILDING 300, STE 201 CAMBRIDGE MA 02139 1 0 0 0 Series Seed Preferred Stock Common Stock 3333333 I See Footnote Series A Preferred Stock Common Stock 12580199 I See Footnote Series B Preferred Stock Common Stock 3740239 I See Footnote All series of Convertible Preferred Stock shall automatically convert on a 4.132-for-1 basis into shares of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering and have no expiration date. The shares are held directly by Atlas Venture Fund X, L.P. ("Atlas Venture Fund X"). The general partner of Atlas Venture Fund X is Atlas Venture Associates X, L.P. ("AVA X LP"). Atlas Venture Associates X, LLC ("AVA X LLC") is the general partner of AVA X LP. Dr. Booth is a member of AVA X LLC and disclaims beneficial ownership of such securities held by Atlas Venture Fund X, except to the extent of his pecuniary interest therein, if any. Exhibit 24 - Power of Attorney /s/ Bruce Booth 2018-06-20