Exhibit 10.6
                          AMENDMENT NO. 1 TO

                        STOCK OPTION AGREEMENT

                            pursuant to the

                             LABONE, INC.

                     2001 LONG-TERM INCENTIVE PLAN

                BONUS REPLACEMENT STOCK OPTION PROGRAM

     This AMENDMENT NO. 1 TO STOCK OPTION AGREEMENT ("Amendment") is dated as of
________________ and entered into by and between LabOne, Inc. ("LabOne"), a
Missouri corporation, and _____________________ the ("Optionee").

      WITNESSETH that:

     WHEREAS, LabOne and the Optionee are parties to one or more Stock Option
Agreements (individually the "Stock Option Agreement" or collectively the "Stock
Option Agreements") relating to stock options granted under the Bonus
Replacement Stock Option Program of the LabOne, Inc. 2001 Long-Term Incentive
Plan (the "Plan"); and

     WHEREAS, LabOne and the Optionee desire to amend the Stock Option
Agreements to provide that acceleration of vesting, exercise (if such stock
options are exercised) and termination of such stock options in connection with
a Corporate Transaction (as hereinafter defined) will be subject to the
condition that the Corporate Transaction shall be consummated; and

     WHEREAS, it is in the best interests of LabOne and the Optionee to include
such provisions in order for LabOne to be able to engage in one or more
Corporate Transactions;

     NOW, THEREFORE, in consideration of the terms and provisions of this
Amendment and other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged by the parties hereto, the parties hereto agree
as follows:

     Section 1. Section 2.5.9 of each outstanding Stock Option Agreement (as
incorporated by reference from the Plan) is hereby amended to read as follows:

          In the event that the Board approves (a) the merger or
          consolidation of LabOne with or into another corporation or
          other entity in which the shareholders of LabOne immediately
          prior to such transaction will beneficially own no voting
          securities or voting securities possessing less than 50% of
          the combined voting power of the then outstanding securities
          of the surviving entity in such transaction (or its parent),
          excluding for purposes of such calculation any such
          shareholder of LabOne who



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           beneficially owns prior to the transaction more than ten
           percent (10%) of the other entity involved in the
           transaction (or its parent), (b) a sale of all or
           substantially all of the assets of LabOne in which
           outstanding securities of LabOne are exchanged for
           securities, cash or other property of any corporation or
           other entity or (c) a liquidation or dissolution of LabOne
           (collectively, a "Corporate Transaction"); the Board may in
           its sole discretion prior to consummation of such
           transaction take any one or more of the following actions
           with respect to outstanding stock options granted under
           this Program: (i) provide that such stock options shall be
           assumed or equivalent stock options shall be substituted by
           the acquiring or succeeding corporation or entity (or an
           affiliate thereof) or (ii) upon thirty (30) days' prior
           written notice to the Optionee, provide that the stock
           option shall be exercisable in full and shall terminate at
           the end of such thirty (30) day period to the extent not
           exercised by such time, at the end of which period the
           stock option shall terminate; provided, however, that
           unless determined otherwise by the Board, the acceleration
           of vesting, exercise (if such stock option is exercised)
           and termination of such stock option under clause (ii)
           shall be subject to the condition that the respective
           Corporate Transaction shall be consummated and such
           acceleration of vesting, exercise (if such stock option is
           exercised) and subsequent termination of such stock option
           shall be effective immediately prior to the effectiveness
           of the respective Corporate Transaction.

     Section 2. A new Section 2.5.9A is added to each Stock Option Agreement and
reads as follows:

           In the event that this stock option is exercised pursuant
           to clause (ii) of Section 2.5.9 in connection with a
           Corporate Transaction in which shares of common stock of
           LabOne are converted into the right to receive cash, unless
           the Optionee elects in writing at the time the stock option
           is exercised pursuant to clause (ii) of Section 2.5.9 to
           receive the Shares issuable upon exercise, (a) the Optionee
           will be entitled to receive upon effectiveness of such
           exercise, in lieu of Shares issuable in connection with
           such exercise of the stock option, an amount in cash equal
           to the number of Shares subject to the stock option
           immediately prior to such exercise multiplied by the amount
           by which the cash consideration per Share payable in such
           Corporate Transaction exceeds the exercise price per Share,
           subject to all applicable federal, state and local tax
           withholding requirements, and (b) the Optionee shall not be
           required to pay the exercise price in connection with such
           exercise.

     Section 3. The remaining provisions of each Stock Option Agreement shall
apply to this Amendment and to such Stock Option Agreement as amended by this
Amendment.



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     IN WITNESS WHEREOF, LabOne, Inc. has caused this Amendment to be executed
in its corporate name, and the Optionee has executed the same in evidence of the
Optionee's acceptance hereof, upon the terms and conditions herein set forth, as
of the day and year first above written.

                               LABONE, INC.



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



                               -------------------------------
                               Optionee