I WAS WONDERING IF HHS SEC. SEBELIUS CAN OVERRIDE THE OPTN

And it turns out she can.  Here's the relevant part of the Code of Federal Regulations:

Title 42: Public Health
PART 121—ORGAN PROCUREMENT AND TRANSPLANTATION NETWORK

§ 121.4   OPTN policies: Secretarial review and appeals.

(d) Any interested individual or entity may submit to the Secretary in writing critical comments related to the manner in which the OPTN is carrying out its duties or Secretarial policies regarding the OPTN. Any such comments shall include a statement of the basis for the comments. The Secretary will seek, as appropriate, the comments of the OPTN on the issues raised in the comments related to OPTN policies or practices. Policies or practices that are the subject of critical comments remain in effect during the Secretary's review, unless the Secretary directs otherwise based on possible risk to the health of patients or to public safety. The Secretary will consider the comments in light of the National Organ Transplant Act and the regulations under this part and may consult with the Advisory Committee on Organ Transplantation established under § 121.12. After this review, the Secretary may:

(1) Reject the comments;

(2) Direct the OPTN to revise the policies or practices consistent with the Secretary's response to the comments; or

(3) Take such other action as the Secretary determines appropriate.

(e) The OPTN shall implement policies and shall:

(1) Provide information to OPTN members about these policies and the rationale for them; and

(2) Update policies developed in accordance with this section to accommodate scientific and technological advances.

UPDATE: A little background on the Organ Procurement and Transplantation Network:

The U.S. Congress established the Organ Procurement and Transplantation Network (OPTN) when it enacted the National Organ Transplant Act (NOTA) of 1984. The act called for a unified transplant network to be operated by a private, non-profit organization under federal contract.
Following further study and recommendations from a task force commissioned through NOTA, the U.S. Department of Health and Human Services (HHS) solicited proposals in 1986 for the operation of the OPTN.
The United Network for Organ Sharing (UNOS) was awarded the initial OPTN contract on September 30, 1986, and has continued to administer the OPTN more than 16 years and four successive contract renewals.
Effective March 16, 2000, HHS implemented a Final Rule establishing a regulatory framework for the structure and operations of the OPTN.