[Genome] Mouse assembly differences

[Dixie Mager]

Hello,
   I have a question about a certain region of the mouse genome assembly.
In the July 2007 version, there is a large gap of about 50,000 bp in the
middle of this region:
chr13:68,101,733-68,249,804

The previous version (Feb. 2006) shows no such gap.  I am interested in this
region so I would be willing to sequence a BAC that spans the gap if
necessary.  However, because of the discrepancy in assemblies, I thought I
would check to determine if the July 2007 assembly is correct before going
to the expense of sequencing. Also, if it is truly a gap, is there a way to
find out when it might be closed?

Thanks very much.

Sincerely,
Dixie Mager