The never‐ending story of geologically ancient DNA : was the model plant A rabidopsis the source of M iocene D ominican amber?

Studies characterizing geologically ancient DNA in plants are rare, and all have reportedly obtained plastid DNA sequences from M iocene fossils in a remarkable state of preservation. Recently, a group made the extraordinary claim of having amplified a geologically ancient M iocene plastid DNA fragment (the rbcL gene) from D ominican amber nuggets, and the organismal source of this DNA was identified as H ymenaea protera ( F abaceae), the plant that produced the fossilized D ominican amber. Assuming that the M iocene sequence is error‐free, reanalysis of the sequence indicates it is probably a technical artifact or an rbcL pseudogene. Furthermore, BLAST similarity searches and phylogenetic analyses strongly suggest that the putative M iocene sequence retrieved from fossilized amber is in fact a modern contaminant from one of the most widely used model plants, A rabidopsis thaliana . © 2013 The Linnean Society of London, Biological Journal of the Linnean Society , 2014, 111 , 234–240.