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... Nevermind.





The 25 April 1997 issue of Nature had a striking paper (Baker et al., 
High Levels of Genetic Changes in Rodents of Chernobyl, Nature, v. 380, 
pp. 707-708) on unusually high mutation rates in the mitochondrial DNA 
of voles captured near the Chernobyl plant vs. more normal rates in 
voles captured 28 km from the plant.  With another paper on high 
mutation rates at minisatellite loci in human germline cells from 
Belarus populations highly exposed to Chernobyl fallout in the same 
issue (Dubrova et al., op. cit., pp. 683-686), the cover of the issue 
had a picture of Chernobyl 4 and the sarcophagus and the news and 
editorial sections of the issue had additional comment on the two papers 
and other questions raised by the accident. 

The current issue (6 November 1997) of Nature has on the last text page 
a retraction of the main conclusion of the Baker et al. paper.  No 
fanfare accompanies the retraction.  Baker et al. were unable to 
replicate their work when the DNA sequencing was done using an automated 
sequencing machine instead of the manual methods used in preparing their 
1996 paper.  The recalculated mutation rates are still elevated, but, 
because of the small sample sizes, no longer statistically significant. 

An interesting issue raised by the original papers and by some earlier 
work (specifically, the study of Chinese populations from regions of 
high background radiation) is the relevance of cytogenetic damage in 
conjunction with absent or unexpectedly low observable health impacts.  
Both the Baker et al. paper and the accompanying News and Views 
commentary by Hillis note that in spite of the high mutation rates the 
vole populations at the Chernobyl site are thriving and reproducing.  
Hillis offers some hypotheses regarding this apparent paradox.  Since I 
am not familiar with the methodology or the literature on the use of 
minisatellite loci and other biomarkers, I would appreciate comments by 
others who are. 

Best regards.

Jim Dukelow
Pacific Northwest National Laboratory
Richland, WA 

js_dukelow@pnl.gov

These thoughts are mine and have not been reviewed and/or approved by my 
management or by the U.S. Department of Energy