The twelfth of Alirio Melendez’s 20-something retractions has appeared, in Clinical and Experimental Pharmacology and Physiology.
Along with the retraction notice, the journal runs letters from the paper’s two co-authors. Melendez writes:
It has come to my attention that significant portions of the text in an article I coauthored in 2006 with PN Pushparaj were plagiarized from previously published works by Karagiannis and El-Osta and Ryther et al. As the corresponding author for this manuscript I would first like to apologise to the authors whose work was plagiarized and state that I was not aware of this at the time. I sincerely apologise for the oversight. Second, I request that the 2006 paper be retracted.
Peter Pushparaj, now of Beacon Biosoft, writes:
Thank you for bringing to my attention the investigation by the National University of Singapore (http://blogs.nature.com/news/2012/12/immunologist-accused-of-misconduct-in-21-papers.html) into the publications of A.J. Melendez, which uncovered overlap between an article I co-authored and previously published articles. [2,3] I would like to express my apologies to the authors of the original articles. The plagiarism escaped my attention during the publication process. Therefore, as a co-author, I agree to the retraction of this article. 
The two letters are followed by the retraction notice:
The following article from Clinical and Experimental Pharmacology and Physiology ‘Short Interfering RNA (siRNA) as a Novel Therapeutic’ by Pushparaj and Melendez published online on 12 May 2006 in Wiley Online Library (http://onlinelibrary.wiley.com) and in Volume 33 (5–6) pp 504–510, has been retracted by agreement between the authors, the journal Editor in Chief Roger Evans and Wiley Publishing Asia Pty Ltd. The retraction has been agreed following an investigation by the National University of Singapore (http://www.nus.edu.sg/) into the publications of A.J. Melendez which uncovered substantial overlap between this article and two previously published articles:
Ryther RCC, Flynt AS, Phillips JA III, Patton JG. siRNA therapeutics: big potential from small RNAs. Gene Ther. 2005;12:5–11, doi: 10.1038/sj.gt.3302356.
Karagiannis TC, El-Osta A. RNA interference and potential therapeutic applications of short interfering RNAs.
Cancer Gene Ther. 2005; 12: 787–795, doi: 10.1038/sj.cgt.7700857.
The paper has been cited 45 times, according to Thomson Scientific’s Web of Knowledge.
Melendez’s letter is signed by “Dr Alirio Melendez-Romero, Independent Scientific Consultant.”