Document:

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                                                                     Exhibit 4.3

                       NONSTATUTORY STOCK OPTION AGREEMENT

                                   PURSUANT TO

                                EDG CAPITAL, INC.
                          2000 LONG-TERM INCENTIVE PLAN

                                    * * * * *

OPTIONEE:

GRANT DATE:

PER SHARE EXERCISE PRICE:

NUMBER OF OPTION SHARES
SUBJECT TO THIS OPTION:

     THIS NONSTATUTORY STOCK OPTION AGREEMENT (this "Agreement"), dated as of
the Grant Date specified above, is entered into by and between EDG CAPITAL,
INC., a New York corporation (the "Company"), and the Optionee specified above,
pursuant to the EDG Capital, Inc. 2000 Long-Term Incentive Plan, as in effect
and as amended from time to time (the "Plan"); and

     WHEREAS, it has been determined under the Plan that it would be in the best
interests of the Company to grant the nonstatutory stock option provided for
herein to the Optionee;

     NOW, THEREFORE, in consideration of the mutual covenants and premises
hereinafter set forth and for other good and valuable consideration, the parties
hereto hereby mutually covenant and agree as follows:

     1. INCORPORATION BY REFERENCE; PLAN DOCUMENT RECEIPT. This Agreement is
subject to the approval of the Plan by the shareholders of the Company. This
Agreement is also subject in all respects to the terms and provisions of the
Plan (including, without limitation, any amendments thereto adopted at any time
and from time to time if such amendments are expressly intended to apply to the
grant of the option hereunder and are permitted to apply by the Plan), all of
which terms and provisions are made a part of and incorporated in this Agreement
as if they were each expressly set forth herein. Any capitalized term not
defined in this Agreement shall have the same meaning as is ascribed thereto
under the Plan. The Optionee hereby acknowledges receipt of a true copy of the
Plan and that the Optionee has read the Plan carefully and fully understands its
content. In the event of any conflict between the terms of this Agreement and
the terms of the Plan, the terms of the Plan shall control.

     2. GRANT OF OPTION. The Company hereby grants to the Optionee, subject to
the approval of the Plan by the shareholders of the Company, as of the Grant
Date specified above, a nonstatutory stock option (this "Option") to acquire
from the Company at the Per Share Exercise Price specified above the aggregate
number of shares of the Common Stock specified above (the "Option Shares"). This
Option is not to be treated as (and is not intended to qualify as) an "incentive
stock option" within the meaning of Section 422 of the Code.

     3. EXERCISE OF THIS OPTION.

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         3.1 This Option shall become exercisable in accordance with and to the
extent provided by the terms and provisions of Section 6.6 of the Plan.

         3.2 Unless earlier terminated in accordance with the terms and
provisions of the Plan, this option shall expire and shall no longer be
exercisable after the expiration of ten years from the Grant Date (the "Option
Period").

         3.3 In no event shall this Option be exercisable for a fractional share
of Common Stock.

     4. METHOD OF EXERCISE AND PAYMENT. This Option shall be exercised by the
Optionee by delivering to the Secretary of the Company or his designated agent
on any business day (the "Exercise Date") a written notice, in such manner and
form as may be required by the Company, specifying the number of the Option
Shares the Optionee then desires to acquire (the "Exercise Notice"). The
Exercise Notice shall be accompanied by payment of the aggregate Per Share
Exercise Price for such number of the Option Shares to be acquired upon such
exercise. Such payment shall be made in the manner set forth in Section 6.5 of
the Plan.

     5. TERMINATION. This Option shall terminate and be of no force or effect in
accordance with and to the extent provided by the terms and provisions of
Section 8 of the Plan. In any event, this Option shall terminate upon the
expiration of the Option Period.

     6. ENTIRE AGREEMENT; AMENDMENT. This Agreement contains the entire
agreement between the parties hereto with respect to the subject matter
contained herein, and supersedes all prior agreements or prior understandings,
whether written or oral, between the parties relating to such subject matter.
This Agreement may only be modified or amended by a writing signed by both the
Company and the Optionee.

     7. GOVERNING LAWS. This Agreement shall be governed by and construed in
accordance with the laws of the State of New York, without reference to the
principles of conflict of laws thereof.

     8. COMPLIANCE WITH LAWS. The issuance of this Option (and the Option Shares
upon exercise of this option) pursuant to this Agreement shall be subject to,
and shall comply with, any applicable requirements of any federal and state
securities laws, rules and regulations (including, without limitation, the
provisions of the Securities Act of 1933, the Exchange Act and the respective
rules and regulations promulgated thereunder) and any other law or regulation
applicable thereto. The Company shall not be obligated to issue this Option or
any of the Option Shares pursuant to this Agreement if any such issuance would
violate any such requirements.

     9. BINDING AGREEMENT; ASSIGNMENT. This Agreement shall inure to the benefit
of, be binding upon, and be enforceable by the Company and its successors and
assigns. The Optionee shall not assign any part of this Agreement without the
prior express written consent of the Company.

     10. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
shall constitute one and the same instrument.

     11. HEADINGS. The titles and headings of the various sections of this
Agreement have been inserted for convenience of reference only and shall not be
deemed to be a part of this Agreement.

     12. FURTHER ASSURANCES. Each party hereto shall do and perform (or shall
cause to be done and performed) all such further acts and shall execute and
deliver all such other agreements, certificates, instruments and documents as
any party hereto reasonably may request in order to carry out the intent and
accomplish the purposes of this Agreement and the Plan and the consummation of
the transactions contemplated thereunder.

     13. SEVERABILITY. The invalidity or unenforceability of any provisions of
this Agreement in any jurisdiction shall not affect the validity, legality or
enforceability of the remainder of this Agreement in such jurisdiction or the
validity, legality or enforceability of any provision of this Agreement in any
other jurisdiction, it being intended that all rights and obligations of the
parties hereunder shall be enforceable to the fullest extent permitted by law.

                                       2
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     14. EMPLOYMENT. Nothing contained in this Agreement shall give the Optionee
any right to be retained in the employ of the Company or affect the right of the
Company to terminate the Optionee's employment with the Company.

                                       3
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     IN WITNESS WHEREOF, the Company has caused this Agreement to be executed by
its duly authorized officer, and the Optionee has hereunto set his hand, all as
of the Grant Date specified above.

                                         EDG CAPITAL, INC.

                                         By:
                                            -----------------------------------
                                         Name:
                                              ---------------------------------
                                         Title:
                                               --------------------------------
                                         OPTIONEE

                                         -------------------------------------

                                       4<PAGE>

================================================================================

                          ABN AMRO MORTGAGE CORPORATION

                                    Depositor

                                       and

                   WASHINGTON MUTUAL MORTGAGE SECURITIES CORP.

                                    Servicer

                                       and

                       STATE STREET BANK AND TRUST COMPANY

                                     Trustee

                                ----------------

                               FIRST AMENDMENT TO
                         POOLING AND SERVICING AGREEMENT

                            Dated September 10, 2001

                                ----------------

                                  $237,316,463

                       Mortgage Pass-Through Certificates

                                  SERIES 2001-1

================================================================================

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                           FIRST AMENDMENT TO POOLING
                           --------------------------
                             AND SERVICING AGREEMENT
                             -----------------------

        THIS FIRST AMENDMENT TO POOLING AND SERVICING AGREEMENT is dated as of
September 10, 2001 (herein referred to as this "First Amendment") and is made by
and between ABN AMRO MORTGAGE CORPORATION, as depositor (the "Depositor"),
WASHINGTON MUTUAL MORTGAGE SECURITIES CORP., as servicer (the "Servicer"), and
STATE STREET BANK AND TRUST COMPANY, as trustee (the "Trustee").

                                    RECITALS
                                    --------

        WHEREAS, the Depositor, the Servicer and the Trustee entered into a
Pooling and Servicing Agreement dated as of April 1, 2001 (the "Agreement"),
pursuant to which (i) the Depositor sold, conveyed and assigned certain Loans to
the Trustee in trust for the benefit of Certificateholders of ABN AMRO Mortgage
Corporation Mortgage Pass-Through Certificates, Series 2001-1, (ii) the Servicer
agreed to service such Loans in accordance with the terms thereof, and (iii) the
Certificates were issued pursuant thereto;

        WHEREAS, this Amendment is being delivered pursuant to Section 10.1(c)
of the Agreement in order to conform the terms of the Agreement to the terms
described in the Prospectus dated October 12, 1999, together with the Prospectus
Supplement dated April 27, 2001.

        NOW, THEREFORE, in consideration of the preceding premises and
assumptions and other good and valuable consideration, the receipt and adequacy
of which are hereby acknowledged, the Depositor, the Trustee, and the Servicer
agree as follows:

Section 1.     Definitions. All capitalized terms used in this First Amendment
               which are not specifically defined herein shall have the meanings
               assigned to them in the Agreement.

Section 2.     Amendment to Agreement. The definition of "Compensating Interest"
               in Article I of the Agreement shall be amended and restated in
               its entirety as follows:

                        Compensating Interest: For any Distribution Date, the
               lesser of (i) the sum of (a) one-twelfth of 0.04% of the
               aggregate outstanding Principal Balance of each Loan on the
               second Due Date preceding such Distribution Date, (b) the
               aggregate Payoff Earnings and (c) the aggregate Payoff Interest
               and (ii) the aggregate Uncollected Interest.

Section 3.     Agreement to Remain in Full Force and Effect. Except as modified
               and amended hereby, all other terms and conditions of the
               Agreement shall remain in full force and effect and are hereby
               ratified and confirmed by the parties hereto.

                                      -2-

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Section 4.     Counterparts. This First Amendment may be executed simultaneously
               in any number of counterparts, each of which counterparts shall
               be deemed an original, and such counterparts shall constitute one
               and the same instrument.

Section 5.     Governing Law. The First Amendment shall be constructed in
               accordance with the internal laws of the State of New York
               applicable to agreements made and to be performed in said State,
               and the obligations, rights and remedies of the parties hereunder
               shall be determined in accordance with such laws.

                                      -3-

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         IN WITNESS WHEREOF, the Depositor, the Servicer and the Trustee have
caused their names to be signed hereto by their respective officers thereunto
duly authorized, all as of the day and year first above written.

                                               ABN AMRO MORTGAGE CORPORATION,
                                                  as Depositor

                                               By /s/ Daniel J.  Fischer
                                                  ------------------------------
                                               Its Vice President
                                                  ------------------------------

                                               STATE STREET BANK AND TRUST
                                               COMPANY,
                                                 as Trustee

                                               By /s/ Clare M. O'Brien
                                                  ------------------------------
                                               Its
                                                  ------------------------------

                                               WASHINGTON MUTUAL MORTGAGE
                                               SECURITIES CORP.,
                                                 as Servicer

                                               By /s/ Michael L. Parker
                                                  ------------------------------
                                               Its President
                                                  ------------------------------

                                      -4-

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