The April 25, 1996 issue of Nature featured on its cover our article concluding that voles living in the Chernobyl environment had an elevated rate of genetic mutation. Our experimental design included double-blind analyses of DNA sequences, the long strings of nucleotides that make up the genetic code. We had determined the genetic sequences manually, a process which involves laborious alignments of genes and even a few judgment calls. Nevertheless, we were confident in our results.

Soon after the paper was published, we acquired an automated sequencer that was more accurate than the manual methods used to sequence DNA. We had archived the tissues from all the animals used in our Nature study, so we decided to re-sequence the genes to compare the methods. To our horror, the automated sequencer failed to replicate the result we reported in Nature. The more accurate method failed to find an elevated mutation rate, even though we repeated the sequencing several times.

[…] In the end, we all agreed that we had an obligation to the scientific community to come clean, and we published a brief retraction in the November 6, 1997 issue of Nature. It was an important lesson in admitting error and coming to terms with our mistakes.

Ronald K. Chesser, Robert J. Baker, “Growing Up with Chernobyl”, American Scientist, Nov-Dec 2006 Vol 94, Num 6, p. 542