A Footnote to a Footnote to a Footnote: More on Schwabe and relaxin
Two scientists who read the second reply to John Timmer complained (one publicly, the other in an email) that I had neglected to inform readers about the refutation of one of Christian Schwabe's claims about the protein relaxin. Their complaints, while in my view misdirected, raise some interesting questions that I'll discuss in my next blog entry.
First, Schwabe's claim, and the testing that challenges it. In this 1999 paper, Schwabe claimed to have isolated the protein relaxin from Ciona intestinalis, a tunicate. Given the usual functional roles of relaxin in vertebrates (e.g., relaxing or widening the birth canal during parturition; hence, its name), this would have been a remarkable discovery, if supported by further research. Ciona doesn't bear live young via a birth canal.
When the complete genome of Ciona was published, however, the sequence for relaxin wasn't there. Thus, Schwabe's 1999 finding was likely the result of contamination.
My correspondent griped that I'd failed to inform readers about this explicitly:
Why didn't you mention in your Schwabe post that his claim of pig relaxin in Ciona is probably due to contamination? It's dishonest not to. Particularly when you lecture your readers on the importance of data, you can't let something like this go unmentioned. A vague reference to Hafner & Korthof just doesn't cut it.
The "vague reference" he mentions is my citation of this paper, which strongly criticizes Schwabe's 1999 FASEB paper. So it seems I needed to do more than cite Schwabe's critics, such as Wilkinson et al. 2005, who also critically evaluated the Ciona claim, and whom I also cited.
Okay: so let's make it really plain: the Ciona relaxin finding was probably the result of contamination. But anyone who followed up my citations would have quickly found this, so...I can't see what I missed.
In any case, the point of my Schwabe reply wasn't to endorse all of Schwabe's arguments or claims, but to illustrate the existence of a genuine controversy about relaxin, which Timmer had denied.
I've got a parallel situation for my two critics to consider, in my next post.