It has come to our attention...

...that a cDNA library previously described as "Life Tech mouse brain" is most probably of rat origin. This situation was initially discovered by Drs. Vadim Gladyshev and Dolph Hatfield of the National Cancer Institute. These investigators obtained clones from I.M.A.G.E Consortium distributors and performed accurate sequencing of the inserts. They found that sequences from this library differed by 10% from other mouse clones but were essentially identical to ESTs from two rat libraries.

Subsequently Dr. John Wootton of NCBI performed extensive sequence analyses of the "Life Tech mouse brain" sequences in dbEST and found that, in every case where both mouse and rat orthologs exist in GenBank, sequences from this library matched rat and were typically 7-12% different from mouse. Further tests showed that contaminating mitochondrial sequences in the "Life Tech mouse brain" library were essentially identical to authentic rat mitochondrial DNA but were 15-18% different from mouse mitochondrial DNA.

After consultations with personnel at Life Technologies, Inc. and Lawrence Livermore National Laboratory, it was concluded that this was not a simple library labelling error and also that the tissue source cannot be determined with certainty. After consultations with the Washington University Genome Sequencing Center and, in the absence of more definite information on the true nature of this library, we are withdrawing from public release all of the 4829 sequence entries in dbEST and GenBank that derive from the "Life Tech mouse brain" library (see below). We have also notified all of the I.M.A.G.E. distributors who may want to consider whether or not to continue distribution of these cDNA clones.

LIBRARY DESCRIPTION

Lib Name:       Life Tech mouse brain
Organism:       Mus musculus

Strain:         C57BL/6J
Organ:          brain
Tissue type:    brain
Develop. stage: adult
Lab host:       DH10B
Vector:         pCMV-SPORT2
R. Site 1:      SalI
R. Site 2:      NotI
Description:    Cloned unidirectionally. Primer: Oligo dT.
pCMV-SPORT2 vector.

Note that this library is described on the I.M.A.G.E. web site as

"Life Tech. adult brain (*see comments in description)"

and the library identifier (LIB_ID) is 220.

We regret any inconvenience that may result from these developments.