Hello UCSC Genome Browser stuff!

My name is Guillermo and I downloaded the aligment data of the cDNAs and EST
over mm9 genome from Table Browser and now I'm comparing these with my gmap
alignment results of the same cDNAs and EST.

I writing to you because I'm not clear about the BLAT alignments filter
parameters you used to generate the alignments. The BLAT program
specification says "Blat produces .... at the DNA level between two
sequences that are of 95% or greater identity ..." (
https://cgwb.nci.nih.gov/goldenPath/help/blatSpec.html). But in addition you
may configured the pslReps filter options to only get the alignments over
certain amount of coverage (-minCover flag). Did you?

I Found some cDNAs cases like BC096042 that at the Table Browser alignments
results only have one alignment, but when I put the BC096042 sequence into
web version BLAT of the Genome Browser, it shows many alignments, which is
expected because there are unfiltered alignments. But what make no sense to
me, is that show me many alignment with identity over 95%. Why this
alignments aren't at Table Browser? Maybe because in this particular case
the BC096042 alignment has a 100% identity and automatically the others
sub-optimals alignments were deleted, Is that right? (see the 100% identity
alignment also at Genome Browser
http://genome.ucsc.edu/cgi-bin/hgc?hgsid=193400045&o=125111868&t=125115317&g=mrna&i=BC096042
)

In order to use your BLAT aligments results from the Table Browser I need to
know your filter parameters. Also I would like to confirm the formula (that
is used at the hyperlink line) to get the identity from the psl line. I need
it to apply to my gmap results and after many attempts, I get to a logical
way to calculate it:

[(match*100/(match+mismatch+Q gap bases) + match*100/(blocksizes
summation)]/2

Please tell me if that's right.

Very thanks for your time.
I look forward to your reply.

-- 
Guillermo Parada. Undergraduate student Biochemistry at Ponticia Univesidad
Católica de Chile.
_______________________________________________
Genome maillist  -  [email protected]
https://lists.soe.ucsc.edu/mailman/listinfo/genome

Reply via email to