EXHIBIT 31.1

CERTIFICATIONS OF PRINCIPAL EXECUTIVE OFFICERPursuant toSection 302 of the Sarbanes-Oxley Act of 2002

I, Edwin C. Quattlebaum, Ph.D., Chief Executive Officer, President and Co-Chairman of the Board of Directors of MetaMorphix, Inc., certify that:

1. I have reviewed this quarterly report on Form 10-QSB/A (Amendment No. 1) of MetaMorphix, Inc. (the Registrant) for the period ended March 31, 2007 (the
Report);

2. Based on my knowledge, this Report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the
circumstances under which such statements were made, not misleading with respect to the period covered by this Report;

3. Based on my knowledge, the financial statements, and other financial information included in this Report, fairly present in all material respects the financial condition, results of
operations and cash flows of the Registrant as of, and for, the periods presented in this Report;

4. The Registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and
15d-15(e)) for the Registrant and have:

a) designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the Registrant, including its
consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this Report is being prepared; b) evaluated the effectiveness of the Registrants disclosure controls and procedures and presented in this Report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of
the period covered by this Report based on such evaluation; and c) disclosed in this Report any change in the Registrants internal control over financial reporting that occurred during the Registrants most recent fiscal quarter (the Registrants fourth fiscal quarter
in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the Registrants internal control over financial reporting.


5. The Registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the Registrants auditors and
the audit committee of the Registrants board of directors (or persons performing the equivalent functions):

a) all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the Registrants ability to record,
process, summarize and report financial information; and b) any fraud, whether or not material, that involves management or other employees who have a
significant role in the Registrants internal control over financial reporting.


| | By:                                                                    | /S/ EDWIN C. QUATTLEBAUM
| | ---------------------------------------------------------------------- | ------------------------
|
| | Edwin C. Quattlebaum, Ph.D.                                           
| | Chief Executive Officer,
    President and Co-Chairman of the Board of
| | Directors of                                                          
| | MetaMorphix, Inc.                                                     

Date: February 29, 2008

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