Dear UCSC Genome Browser team,

We have problems to recover your online blat search results with our local
blat searches. Our problem is that we get a lot more hits than the online
search reports but we can not figure out why they are not reported.

We are using the stand alone blat version with the same parameters as
suggested on the FAQ page and I compute the score like you do in your script
(psl.c). We are blatting DNA and use the same genome version.

blat -stepSize=5 -repMatch=1024 -minScore=0 -minIdentity=0 canFam2.2bit
in.fa temp.psl
(pslWithScores.psl has the score and a percent identity in its first two
columns and in temp.psl you will find the output file from the local blat
search).

When we blat the sequence attached (in.fa) we get the best score 597, while
the web-tool's best hit has the score 106. As you can see, we also get this
hit (so the computation of the score is correct), but we also get a lot more
(and not few better ones). Is it something we need to change about the
parameters or do we need to filter the results afterwards?

Here is an example:

138    22    0    0    5    349    5    228    +    Emx2os_Human    7282
3898    4407    chr24    50763139    31027810    31028198    7
66,27,8,10,7,8,34,    3898,3977,4014,4038,4048,4358,4373,
31027810,31027890,31027925,31028034,31028107,31028156,31028164,
This is your best match (according to the online tool) as is in the psl
output file, which scores 106.

774    121    0    0    27    3588    29    60189    -    Emx2os_Human
7282    69    4552    chr28    44191819    30945073    31006157    33
8,4,17,8,32,29,51,12,22,95,17,15,31,8,38,6,6,36,38,6,16,39,10,7,24,21,22,67,10,22,144,28,6,
2730,2744,2749,2766,2780,2889,3578,3683,3703,3730,3950,3977,3999,4060,4068,4107,4113,4537,4729,4774,4781,6119,6164,6232,6246,6352,6373,6788,6943,6966,6992,7179,7207,
30945073,30945094,30945098,30945116,30945129,30945237,30945598,30945689,30945719,30945742,30945974,30946002,30946023,30946079,30946098,30946136,30946143,30946252,30946463,30946509,30946520,30946607,30946651,30946708,30946719,30946823,30946845,31005736,31005884,31005908,31005930,31006116,31006151,
This is the highest scoring hit we got. The score is 597, but between this
one and 106 there are many better scores. Why do you not report this hits?

Kind regards,
ilinca tudose
_______________________________________________
Genome maillist  -  [email protected]
https://lists.soe.ucsc.edu/mailman/listinfo/genome

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