SecProbe.io

May 1, 2015

Via E -mail
John D. Mendlein, Ph.D.
Chief Executive Officer and Executive Chairman
aTyr Pharma, Inc.
3545 John Hopkins Court, Suite #250
San Diego, CA 92121

Re: aTyr  Pharma, Inc.
Amendment No. 1 to Registration Statement on Form S -1
Filed April 27, 2015
  File No. 333 -203272

Dear Dr. Mendlein :

We have reviewed your  amended  registration statement  and have the following comment.

Please respond to this letter by amending your registration statement and providing the
requested information .  If you do not believe our comment applies  to your facts and
circumstances or do not believe an amendment is appropriate, please tell us why in your
response.

After reviewing any amendment to your registration statement and the information you
provide in response to this comment , we may have  additional comments.

Report of Independent Registered Public Accounting Firm, Page F -2
Exhibit 23.1:  Consent of Indepe ndent Registered Public Accounting Firm

1. Please have your auditors remove the restrictive language from their report and consent
and sign them in the filing for which you request effectiveness.

We urge all persons who are responsible for the accuracy and adequacy of the disclosure
in the filing to be certain that the filing includes the information the Securities Act of 193 3 and
all applicable Securities  Act rules require.   Since the company and its management are in
possession of all facts relating to a c ompany’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have made.

Notwithstanding our comments, in the event you request acceleration of the effective date
of the pending regist ration statement , please provide  a written statement from the company
acknowledging that:

John D. Mendlein, Ph.D.
aTyr Pharma, Inc.
May 1, 2015
Page 2

  should the Commission or the staff, acting pursuant to delegated authority, declare the
filing effective, it does not foreclose the Commission from taking any action with respect
to the filing;

 the action of the Commission or the staff, acting pursuant to delegated authority, in
declaring the filing effective, does not relieve the company from its full responsibility for
the adequacy and accuracy of the disclosure in the filing; and

 the company may not assert staff comments and the declaration of effectiveness as a
defense in any proceeding initiated by the Commission or any person under the federal
securities laws of the United States.

Please refer to Rules 460 and 461 regarding reque sts for  acceleration .  We will consider a
written request for acceleration of the effective date of the registration statement as confirmation
of the fact that those requesting acceleration are aware of their respective responsibilities under
the Securitie s Act of 1933 and the Securities Exchange Act of 1934 as they relate to the proposed
public offering of the securities specified in the above registration statement.  Please allow
adequate time  for us to review any amendment prior to the requested effectiv e date of the
registration statement.

You may contact Mark Brunhofer at (202) 551 -3638 if you have questions regarding
comments on the financial statements and related matters.  Please contact Matthew Jones at
(202) 551 -3786, Bryan Pitko at (202) 551 -3203 or me at (202) 551 -3715 with any other
questions.

Sincerely,

 /s/ Jeffrey P. Riedler

Jeffrey P. Riedler
Assistant Director

cc:  Kingsley L. Taft
Maggie L. Wong
Mitzi Chang
Goodwin Procter LLP
3 Embarcadero Center, 24th Floor
San Francisco, CA 94111