POWER OF ATTORNEY



 Know all by these presents, that the undersigned hereby constitutes

and appoints each of JOSEPH W. LA BARGE and JEFFREY D. KAHN, and with full

power of substitution, signing singly, the undersigned's true and lawful

attorney-in-fact to:



 (1)  prepare, execute in the undersigned's name and on the

undersigned's behalf, and submit to the U.S. Securities and Exchange Commission

(the "SEC") a Form ID, including amendments thereto, and any other documents

necessary or appropriate to obtain codes and passwords enabling the undersigned

to make electronic filings with the SEC of reports required by Section 16(a) of

the Securities and Exchange Act of 1934 or any rule or regulation of the SEC;



 (2)  execute for and on behalf of the undersigned, in the

undersigned's capacity as an officer and/or director of Spark Therapeutics,

Inc. (the "Company"), Forms 3, 4 and 5 in accordance with Section 16(a) of the

Securities Exchange Act of 1934 and the rules thereunder;





do and perform any and all acts for and on behalf of the

undersigned which may be necessary or desirable to (A) complete and execute

any such Forms 3, 4 or 5, (B) complete and execute any amendment or amendments

thereto and (C) timely file such forms with the United States Securities and

Exchange Commission and any stock exchange or similar authority; and



 (3)  do and perform any and all acts for and on behalf of the

undersigned which may be necessary or desirable to complete and execute

any such Forms 3, 4 or 5 and timely file such forms with the SEC and

and any stock exchange or similar authority; and



 (4)  take any other action of any type whatsoever in connection

with the foregoing which, in the opinion of such attorney-in-fact, may be of

benefit to, in the best interest of, or legally required by, the undersigned,

it being understood that the documents executed by such attorney-in-fact

on behalf of the undersigned pursuant to this Power of Attorney shall be in

such form and shall contain such terms and conditions as such attorney-in-fact

may approve in such attorney-in-fact's discretion.



 The undersigned hereby grants to each such attorney-in-fact full power

and authority to do and perform any and every act and thing whatsoever requisite,

necessary, or proper to be done in the exercise of any of the rights and powers

herein granted, as fully to all intents and purposes as the undersigned might or

could do if personally present, with full power of substitution or revocation,

hereby ratifying and confirming all that such attorney-in-fact, or such attorney-

in-fact's substitute or substitutes, shall lawfully do or cause to be done by

virtue of this power of attorney and the rights and powers herein granted. The

undersigned acknowledges that the foregoing attorneys-in-fact, in serving in such

capacity at the request of the undersigned, are not assuming, nor is the Company

assuming, any of the undersigned's responsibilities to comply with Section 16 of

the Securities Exchange Act of 1934.



 This Power of Attorney shall remain in full force and effect until the

undersigned is no longer required to file Forms 3, 4, and 5 with respect to

the undersigned's holdings of and transactions in securities issued by the

Company, unless earlier revoked by the undersigned in a signed writing delivered

to the foregoing attorneys-in-fact.



 IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney

to be executed on the day and year set forth below.





THE CHILDREN'S HOSPITAL OF

PHILADELPHIA FOUNDATION



By: /s/Steven M. Altschuler, MD  WITNESS:   /s/ Osceola Williams

Steven M. Altschuler, MD      Osceola Williams

Chief Executive Officer



Dated: January 29, 2015   Dated: January 29, 2015