Exhibit 4.1

DP SEE REVERSE FOR CERTAIN DEFINITIONS COMMON STOCK COMMON STOCK INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE THIS CERTIFIES THAT is the owner of Dicerna Pharmaceuticals, Inc. transferable on the books of the Corporation in person or by attorney upon surrender of this certificate duly endorsed or speciman assigned. This certificate is not valid until countersigned by the Transfer Agent and registered by the Registrar. WITNESS the facsimile signatures of its duly authorized officers. Dated: FULLY PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK, $0.0001 PAR VALUE, OF SECRETARY CHIEF EXECUTIVE OFFICER S H A R E S Dicerna Pharmaceuticals, Inc. CUSIP 253031 10 8 COUNTERSIGNED AND REGISTERED: AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC (Brooklyn, NY) TRANSFER AGENT AND REGISTRAR By: AUTHORIZED SIGNATURE

SIGNATURE(S) GUARANTEED: THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15. TEN COM — as tenants in common TEN ENT — as tenants by the entireties JT TEN — as joint tenants with right of survivorship and not as tenants in common Additional abbreviations may also be used though not in the above list. For value received, hereby sell, assign and transfer unto THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE, IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT, OR ANY CHANGE WHATEVER. The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations: NOTICE: Shares PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS INCLUDING ZIP CODE OF ASSIGNEE of the Common stock represented by the within Certificate, and do hereby irrevocably constitute and appoint to transfer the said stock on the books of the within-named Corporation with full power of substitution in the premises. Dated PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE UNIF GIFT MIN ACT Custodian (Cust) (Minor) under Uniform Gifts to Minors Act (State) Attorney