**EXHIBIT 31.1**

**CERTIFICATIONS OF PRINCIPAL EXECUTIVE OFFICER Pursuant to Section 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 of MetaMorphix, Inc. (the “Registrant”) for the period ended June 30, 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 thecircumstances 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 ofoperations 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) and15d-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 andthe 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