United States securities and exchange commission logo

                              August 19, 2020

       Eli Casdin
       Chief Executive Officer
       CM Life Sciences, Inc.
       c/o Corvex Management LP
       667 Madison Avenue
       New York, NY 10065

                                                        Re: CM Life Sciences,
Statement on Form S-1
                                                            Filed August 14,
                                                            File No. 333-246251

       Dear Mr. Casdin:

              We have reviewed your 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 amending your registration
statement and providing the
       requested information. 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 any amendment to your registration statement and
the information you
       provide in response to these comments, we may have additional comments.

       Registration Statement on Form S-1


   1.                                                   We note you disclose on
pages 59 and 125 that "the federal courts shall be the exclusive
                                                        forum for the
resolution of any complaint asserting a cause of action arising under the
                                                        Securities Act against
us or any of our directors, officers, other employees or agents."
                                                        Please state that there
is uncertainty as to whether a court would enforce such provision
                                                        and state that
investors cannot waive compliance with the federal securities laws and the
                                                        rules and regulations
thereunder. In that regard, we note that Section 22 of the Securities
                                                        Act created concurrent
jurisdiction for federal and state courts over all suits brought to
                                                        enforce any duty or
liability created by the Securities Act or the rules and regulations
 Eli Casdin
CM Life Sciences, Inc.
August 19, 2020
Page 2
2.    Please expand your disclosure to clarify Casdin Capital's current and
future role in
      connection with any acquisition strategy. In that regard, we note you
disclose that you
      intend to draw upon "Casdin Capital's scientific process" as you evaluate
targets, that
      Casdin Capital will provide you with "a pipeline of proprietary
opportunities that will
      continue to increase as new players enter" and that you intend to
leverage its "position as
      more than just an investor, but a key partner."
        We remind you that the company and its management are responsible for
the accuracy
and adequacy of their disclosures, notwithstanding any review, comments, action
or absence of
action by the staff.

       Refer to Rules 460 and 461 regarding requests for acceleration. Please
allow adequate
time for us to review any amendment prior to the requested effective date of
the registration

       You may contact Jennifer O'Brien, Staff Accountant, at (202) 551-3721 or
Horowitz, Accounting Branch Chief, at (202) 551-3311 if you have questions
comments on the financial statements and related matters. Please contact Karina
Dorin, Staff
Attorney, at (202) 551-3763 or Loan Lauren Nguyen, Legal Branch Chief, at (202)
with any other questions.

FirstName LastNameEli Casdin
                                                            Division of
Corporation Finance
Comapany NameCM Life Sciences, Inc.
                                                            Office of Energy &
August 19, 2020 Page 2
cc:       Colin Diamond
FirstName LastName