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Exhibit (a)(1)(D)

Offer To Purchase For Cash
All Outstanding Shares of Common Stock
of
GENOPTIX, INC.
at
$25.00 NET PER SHARE
Pursuant to the Offer to Purchase dated January 28, 2011
by
GO MERGER SUB, INC.
a direct wholly-owned subsidiary of
NOVARTIS FINANCE CORPORATION
an indirect wholly-owned subsidiary of
NOVARTIS AG

THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, ON FRIDAY, FEBRUARY 25, 2011, UNLESS THE OFFER IS EXTENDED. 

January 28, 2011

        To Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees:

        We have been engaged by GO Merger Sub, Inc., a Delaware corporation (the "Purchaser") and a wholly-owned subsidiary of Novartis Finance Corporation, a New York corporation, to act as Dealer Manager in connection with the Purchaser's offer to purchase (the "Offer") all outstanding shares of common stock, par value $0.001 per share (the "Shares"), of Genoptix, Inc., a Delaware corporation, at a purchase price of $25.00 per Share net to the seller in cash, without interest and less any required withholding taxes, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated January 28, 2011 (the "Offer to Purchase"), and the related Letter of Transmittal enclosed herewith.

        For your information and for forwarding to your clients for whom you hold Shares registered in your name or in the name of your nominee, we are enclosing the following documents:

        1.     The Offer to Purchase;

        2.     The Letter of Transmittal for your use in accepting the Offer and tendering Shares and for the information of your clients, together with "Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9" providing information relating to backup withholding of U.S. federal income tax;

        3.     A Notice of Guaranteed Delivery to be used to accept the Offer if the Shares and all other required documents cannot be delivered to JPMorgan Chase Bank, N.A. (the "Depositary") by the expiration of the Offer or if the procedure for book-entry transfer cannot be completed by the expiration of the Offer;

        4.     A form of letter which may be sent to your clients for whose accounts you hold Shares registered in your name or in the name of your nominee, with space provided for obtaining such clients' instructions with regard to the Offer; and

        5.     A return envelope addressed to the Depositary for your use only.

Certain conditions to the Offer are described in Section 15 of the Offer to Purchase.

We urge you to contact your clients as promptly as possible. Please note that the Offer will expire at 12:00 midnight, New York City time, on Friday, February 25, 2011 (which is the end of the day on February 25, 2011), unless the Offer is extended. Except as otherwise described in Section 4 of the

Offer to Purchase previously tendered Shares may be withdrawn at any time until the Offer has expired and, if the Purchaser has not accepted such Shares for payment by March 28, 2011, such Shares may be withdrawn at any time after that date until the Purchaser accepts Shares for payment.

        For Shares to be properly tendered pursuant to the Offer, (a) the share certificates or confirmation of receipt of such Shares under the procedure for book-entry transfer, together with a properly completed and duly executed Letter of Transmittal, including any required signature guarantees, or an "Agent's Message" (as defined in the Offer to Purchase) in the case of book-entry transfer, and any other documents required in the Letter of Transmittal, must be timely received by the Depositary or (b) the tendering stockholder must comply with the guaranteed delivery procedures, all in accordance with the Offer to Purchase and Letter of Transmittal.

        The Purchaser will not pay any fees or commissions to any broker or dealer or other person (other than the Depositary and the Information Agent as described in the Offer to Purchase) for soliciting tenders of Shares pursuant to the Offer. The Purchaser will, however, upon request, reimburse brokers, dealers, commercial banks and trust companies for reasonable and necessary costs and expenses incurred by them in forwarding materials to their customers. The Purchaser will pay all stock transfer taxes applicable to its purchase of Shares pursuant to the Offer, subject to Instruction 6 of the Letter of Transmittal.

        Any inquiries you may have with respect to the Offer should be addressed to, and additional copies of the enclosed materials may be obtained from, the Information Agent or the undersigned at the addresses and telephone numbers set forth on the back cover of the Offer to Purchase.

Very truly yours,

Goldman, Sachs & Co.

Nothing contained herein or in the enclosed documents shall render you the agent of the Purchaser, the Dealer Manager, the Information Agent or the Depositary or any affiliate of any of them or authorize you or any other person to use any document or make any statement on behalf of any of them in connection with the Offer other than the enclosed documents and the statements contained therein.

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Exhibit (a)(1)(D)