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                             August 19, 2020

       Joshua T. Brumm
       President and Chief Executive Officer
       Dyne Therapeutics, Inc.
       830 Winter Street
       Waltham, MA 02451

                                                        Re: Dyne Therapeutics,
                                                            Draft Registration
Statement on Form S-1
                                                            Submitted July 23,
                                                            CIK No. 0001818794

       Dear Mr. Brumm:

              We have reviewed your draft registration statement and have the
following comments. In
       some of our comments, we may ask you to provide us with information so
we may better
       understand your disclosure.

              Please respond to this letter by providing the requested
information and either submitting
       an amended draft registration statement or publicly filing your
registration statement on
       EDGAR. If you do not believe our comments apply to your facts and
circumstances or do not
       believe an amendment is appropriate, please tell us why in your

             After reviewing the information you provide in response to these
comments and your
       amended draft registration statement or filed registration statement, we
may have additional

       Draft Registration Statement on Form S-1 submitted July 23, 2020

       Prospectus summary
       Overview, page 1

   1.                                                   Please revise the
"Overview" section on page 1 to highlight that your operations are
                                                        preclinical in nature.
       Our portfolio, page 3

   2.                                                   We note the inclusion
of your Cardiac/Metabolic programs in your pipeline table on page
                                                        3. Given the status of
development and the limited disclosure on page 116 regarding these
 Joshua T. Brumm
FirstName  LastNameJoshua  T. Brumm
Dyne Therapeutics, Inc.
August 19, NameDyne
           2020       Therapeutics, Inc.
Page 2 19, 2020 Page 2
FirstName LastName
         programs, it seems premature to highlight these programs prominently
in your Summary
         pipeline table. Accordingly, please revise to remove these programs
from the Summary
         table or advise.
Our strategy, page 4

3.       We note your disclosure on page 5 that your strategy is to "rapidly"
advance your lead
         programs in DM1, DMD and FSHD to clinical proof-of-concept and
approval. Please
         revise these statements and any similar disclosure to remove any
implication that you will
         be successful in commercializing your programs in a rapid or
accelerated manner as such
         statements are speculative.
Use of proceeds, page 85

4.       Please revise to disclose the approximate amount of proceeds that you
intend to allocate
         toward each of the programs you identify in the Summary pipeline
table. In your revised
         disclosure, please indicate how far the proceeds from the offering
will allow you to
         proceed with the continued development of each of your programs.
Business, page 113

5.       Please revise the prospectus to remove any statements that suggest the
safety and efficacy
         of your platforms, as these determinations are the exclusive authority
of the FDA or other
         regulators. For example, we note your statements that in murine and
non-human primate
         studies, you have "effectively delivered" antisense oligonucleotides
         phosphorodiamidate morpholino oligomers to genetic targets within
muscle tissue
         resulting in "durable, disease-modifying, functional benefit" across
multiple indications
         and disease models, and that your proprietary Fabs are engineered to
bind to TfR1 to
         enable targeted "effective delivery" of nucleic acids.
Clinically validated linker, page 114

6.       Please provide support for your statement that the Val-Cit linker has
been clinically
         validated as safe and effective in approved products.
Our strategy, page 117

7.       We note the following statement: "If our clinical trials are
successful, we plan to meet
         with regulatory authorities to discuss expedited regulatory approval
strategies." Please
         remove this statement from the prospectus, as it implies that
expedited approval may be
         obtained, which is not within the company's control or known at this
Myotonic dystrophy type 1 (DM1), page 125

8.       The illustration provided on page 125, the second figure on page 129,
and the image on
         page 133 contains text that is illegible. Please revise accordingly.
 Joshua T. Brumm
Dyne Therapeutics, Inc.
August 19, 2020
Page 3
Intellectual Property, page 143

9.     For the patent applications disclosed on page 144, please revise to
provide the
       identification of all applicable jurisdictions where patents
applications are pending.
License agreement with the University of Mons, page 147

10.    Please disclose when the latest to expire patent is scheduled to expire.
Financial Statements
Commitments and contingencies
Other contractual obligations, page F-25

11.    We note your disclosure of your agreement with University of Mons on
page 147. Please
       revise your filing to disclose the material terms of the agreement, such
as a description of
       any significant milestones and anticipated patent expiration dates.

12.    Please supplementally provide us with copies of all written
communications, as defined in
       Rule 405 under the Securities Act, that you, or anyone authorized to do
so on your behalf,
       present to potential investors in reliance on Section 5(d) of the
Securities Act, whether or
       not they retain copies of the communications.
       You may contact Eric Atallah at 202-551-3663 or Al Pavot at 202-551-3738
if you have
questions regarding comments on the financial statements and related matters.
Please contact
Laura Crotty at 202-551-7614 or Jeffrey Gabor at 202-551-2544 with any other

FirstName LastNameJoshua T. Brumm
                                                              Division of
Corporation Finance
Comapany NameDyne Therapeutics, Inc.
                                                              Office of Life
August 19, 2020 Page 3
cc:       Stuart M. Falber, Esq.
FirstName LastName