Accession question

[Tom Schneider]

 ==> #1: [Weight=100, 1 word; pyrc] 
LOCUS       ECOPYRC      2046 bp ds-DNA             BCT       15-SEP-1989 
DEFINITION  Escherichia coli pyrC gene encoding dihydroorotase, complete cds. 
ACCESSION   D00002 N00002 
KEYWORDS    dihydroorotase; pyrC; pyrimidine nucleotide metabolism. 
SOURCE      Escherichia coli DNA, clone pEC135. 
  ORGANISM  Escherichia coli 
 
     #3: [Weight=59, 1 word; pyrc] 
LOCUS       ECOPYRH      2046 bp ds-DNA             BCT       18-MAY-1991 
DEFINITION  E. coli pyrC gene for dihydroorotase 
ACCESSION   X04469 D00002 N00002 
KEYWORDS    4,5-L-dihydroorotate amidohydrolase; dihydro-orotase; 
            unidentified reading frame. 
SOURCE      Escherichia coli DNA. 
 
Identical accession numbers?  I thought this was impossible!!!!
The sequences are identical.

If accession numbers are assigned to a unique sequence, and they only join
together when a merge is made, then how could two entries have the same
numbers?  Has anyone looked through the entire database for other duplications
like this?  Software which relies on these being unique will miss entries.

  Tom Schneider
  National Cancer Institute
  Laboratory of Mathematical Biology
  Frederick, Maryland  21702-1201
  toms at ncifcrf.gov


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