The BDGP and DHGP has released a new assembly of Drosophila
melanogaster called Release_5.  Release_5 is a single 
comprehensive assembly of the entire genome (both euchromatin 
and heterochromatin).  This new assembly has several important
features, most notably additional high quality assembled
heterochromatin on the major chromosome arms and high quality
assembled heterochromatin segments mapped to the base of the
arms but not attached to the major arm assemblies.

FlyBase and the DHGP are in the process of migrating our gene
annotations onto Release_5.  We anticipate that the first
annotation set on Release_5, called version Release_5.1, will
be available on FlyBase and in GenBank in August 2006.  

Until then, we are adding the unannotated Release_5 melanogaster
genome to our set of genome BLAST databases.  The default for
melanogaster will remain the Release_4 arms plus the Release_3.2b
heterochromatin, until Release_5.1 becomes available.