EXHIBIT 4.1


            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

     We consent to the reference to our firm under the caption
"Experts-Independent Registered Public Accounting Firm" and to the use of our
report dated April 18, 2018 in the Amendment No. 2 to the Registration Statement
(File No. 333-222401) and related Prospectus of Guggenheim Defined Portfolios,
Series 1727.

                                                          /s/ Grant Thornton LLP
                                                          ----------------------
                                                              GRANT THORNTON LLP


Chicago, Illinois
April 18, 2018