Enhanced Access to
Taxonomy Database

New Human-Mouse
Homology Map

Catch the Gene
Expression Omnibus

A Pair of Pathogens
Added to GenBank

Protein Molecular
Weight Field
Now in Entrez

OMIM In Entrez:
New Searching Power

Web Server
Software Available
for BLAST

Recent Publications

News Briefs

BLAST Lab

PSI-BLAST 2.1
Offers Compostion-
Based Statistics

Slight Address Change
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Masthead

A new version of the Human-Mouse Homology Map is now online. The new map differs from the Davis Human/Mouse Homology Map in that it is produced by integrating orthologs identified at The Jackson Laboratory with putative orthologs identified by sequence homology. The latter step involves the identification of orthologous human/mouse sequence pairs by BLAST comparisons using non-EST mRNA.

To identify human-mouse sequence pairs, two BLAST analyses are performed: one in which the human mRNA is the query and one in which the mouse mRNA is the query. Only pairs exhibiting reciprocal best BLAST scores are included in this analysis. Pairs for which the identification of a reciprocal best hit is not unambiguous, or pairs identified by BLAST that are in conflict with curated homology information are reviewed before being included on the map.

Several new features are offered, including reporting representative STSs associated with the loci on the map, linking human cytogenetic locations to NCBI’s MapViewer, providing links to alignments of representative sequences via BLAST2Sequences, and linking gene symbols to LocusLink reports.

The page display style for the new map is determined by the chromosome that is selected as the master. For example, when beginning with a mouse chromosome as the master, genes are ordered based on mouse genetic positions as determined by the Mouse Genome Database (MGD). When a human chromosome is the master map, gene order is determined first by available sequence information, and then by cytogenetic location. Genes with unknown chromosomal positions are grouped at the bottom of the page. In addition, an effort has been made to virtually map genes in which the position of one ortholog is known, but the other is unknown. These genes are indicated by the hatched bars.
—DW

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