Frequently Asked Questions: Display Problems

Topics

• Problems accessing the Genome Browser or Blat
• Error message - "Can't find organism"
• Resetting the Genome Browser display to default settings
• Errors in the LiftOver output

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Problems accessing the Genome Browser or Blat

I'm having problems accessing the Genome Browser and blat server site. When I try to do a blat search, I get the message "Couldn't connect to blat1 17779. Connection refused.

The Genome Browser database has a regularly scheduled maintenance window during the hours of 5:00-6:00 p.m. Pacific Time on Thursday afternoons. Although we reserve one hour for this maintenance, the actual down time is usually only a few minutes.

If you are experiencing an access problem outside of this timeframe, send an out-of-service report to genome-www@soe.ucsc.edu When reporting a problem with either our website or a link on one of our web pages, please provide us with specific information to help expedite a resolution (e.g. an exact web link, a specific gene, etc.). We try to respond to problems as quickly as possible. You may want to bookmark one of our mirror servers to avoid any interruption to your research.

Error message - "Can't find organism"

When I try to start the Genome Browser, I get an error message that it can't find the assembly.

Your browser may be defaulting to an assembly version that has been moved to our archives. To clear this setting, open the Genome Browser gateway page and manually select the assembly you'd like to view.

Resetting the Genome Browser display to default settings

Is there an easy way to restore all the tracks to their original settings without changing them one at a time?

To return all of the browser's tracks to their default settings, click the Genome Browser->Reset All User Settings option in the top menu bar. Be aware that this action will remove all custom tracks and will clear all track filter and configuration settings that may have modified.

Errors in the LiftOver output

When I run LiftOver, I get some errors in my output and do not know what they mean.

Error messages from liftOver are usually related to some complexity encountered when trying to map a region between two assemblies. This sometimes means that a part of the assembly was either removed or significantly rearranged between the two. Below is a description of the errors:

• Deleted in new: This indicates that nothing in the new assembly aligns with that region of the original assembly. This error could be due to any of several reasons, such as the region being part of a problematic contig or later being identified as highly repetitive and masked before we built the alignment. This message is also displayed when no sequence name matches are found between your input regions and the file used to map between assemblies. If this is coming up for many or all of your items, check that the sequence names (e.g. chr1, chr2) match the names we use on the query assembly selected.
• Partially deleted in new: This means that only a fragment of the original assembly aligns with the new assembly. However, the alignment is below the threshold percentage of bases, and it is insufficient to map the entire region. By default, this threshold is set at 95% of the input region size, but it can be adjusted using the "Minimum ratio of bases that must remap" option.
• Split in new: In this case, the original assembly region is fragmented across multiple locations in the new assembly, but all hits fall below the threshold percentage of bases to be considered a match. The threshold is set at 95% of the input region size, but it can be adjusted via the "Minimum ratio of bases that must remap" option.
• Duplicated in new: The original assembly region maps to multiple locations in the new assembly, with strong matches exceeding the base percentage threshold. However, no specific region is selected due to the absence of the "Allow multiple output regions" option. The remap threshold can also be configured with the "Minimum ratio of bases that must remap" setting.
• Boundary problem: This error occurs when there is a missing start or end base in an exon.

We recommend exploring the hg38 and hg19 GRC Incident tracks, which highlights areas where assembly issues have been identified or resolved by the Genome Reference Consortium (GRC). It is important to note that mappings between genome assemblies are not always symmetrical, so you may encounter differences when lifting between assemblies (e.g., from hg19 to hg38). These discrepancies are expected, as regions in new assemblies may shift, and corrections for previous assembly errors (such as bad data) are made, which is reflected in the GRC Incident track. We also recommend reviewing the liftOver tracks on hg38 and hg19 to visualize the liftOver alignment and identify which parts of the input region overlap or don't overlap. Both hg38 and hg19 include Diff tracks that show exactly what regions are included, excluded, or differ between the assemblies, as well as any changes in the contigs used to assemble specific regions.