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appended to this chapter, along with the form specified, and a sample query returned.
Indexed flat-files which provide full-text searching have been a standard feature of
the Genera software. In 1994, MaizeDB, http://www.agron.missouri.edu employed
Genera upgraded for WWW form and full-text query access; the upgrade also
permitted facile linking with external databases. Data relevant to the maize genome
exists in major sequence, reference and germplasm databases, as well as other
species-specific genome databases, including E. coli, yeast and other plant genomes.
Reciprocal, record-to-record links with SwissProt were established June 1994, and
followed soon thereafter with reciprocal links to GRIN, the Germplasm Resource
Information Network for the US.
DATA CONTENT
MaizeDB maintains the current genetic maps for the community, together with
supporting documentation, and information about gene function and expression.
Supporting documentation may includes( 1) data analyses summaries, such as QTL
experiments; (2) raw data, map scores and recombination data; (3) references, with
address information for many of the authors; (4) access to research tools, including
genetic stocks, DNA clones and PCR primer sequences. Gene function and
expression are provided in comments on the locus pages, in the gene product, mutant
phenotype, trait information about mapped and unmapped. Gene function and
expression are provided in comments on the locus records, by links to gene product,
mutant phenotype, and agronomic traits.
Over 110,000 records are currently maintained by MaizeDB; major classes of
information are summarized in the below table. There may be upwards of some
40,000 genes in maize. Of the 15,764 maize loci in the database, there are 6,028
genes, where 1,188 have been mapped to chromosome arm or better by mutant
phenotype or single copy probe. The MNL Gene List, now includes 1,512 unique
genetic factors of which 827 have some map position. Loci have expanded from the
62 phenotypically identified genes on the 1935 map compilation to include
pseudogenes, probed sites (PCR or RFLP); restriction fragments (mitochondrial
maps), chromosomal segments, points and QTL (quantitative trait loci).