Hard to say. It seems that the statement about this being in conflict with the standards set by COPE is wrong; it is permissible to retract a paper that is incorrect due to honest mistake - and the editor clearly states that too few animals were used in order to get reliable results.
So far so good. There is no ground for boycott. On the other hand, the open letter implies that there are other things going on here and about them I have to say I am agnostic...
You are wrong Stefan, the journal editor admitted the paper contained no error, intentional or otherwise, and none of the other COPE criteria applies. It is an outright censorship of science by the journal and its publisher, most likely on behalf of the biotech industry. We have attracted over 1000 signatures in less than 6 days. Obviously, a lot of people don't agree with you.
Please see here: http://www.i-sis.org.uk/Open_letter_to_FCT_and_Elsevier.php
It doesn't sound like a mistake at all. It sounds like a limitation of the study, a truely typical "too few repetitions experiment design" which lowers statistical power in the ensuing analyses. If all the experiments with too few repetitions were to be retracted, then I guess thousands (most?) of the 'omic' papers would need to be retracted?! For instance many published transcriptome experiments have ... no repeats (because kits are too expensive, or samples are too rare)!
Wouldn't it be more constructive to write a critical response encouraging the experiment to be repeated with more rats so the initial conclusions can be confirmed or refuted? Pretending the results never existed just doesn't seem like the best road to progress...
You are right Pascal. That's why nearly 4 800 have signed an open letter condemning the retraction and pledging to boycott the publisher. See here: http://www.i-sis.org.uk/Open_letter_to_FCT_and_Elsevier.php