Hello,

The coordinates will only pull out a sequence if there is overlap in the 
*matched bases* of the alignment between the target (est, mrna, etc.) and the 
genomic sequence. The intron region is not a part of the aligned base set for 
all but one of the ests, the region represents *unmatched bases* for these. So 
a search will only pull out the single (suspicious) sequence with the intron 
alignment with matched bases at this location. From experience, this single 
sequence seems like it is probably genomic contamination from the EST's library 
construction process. But, you can check out the genbank record and the other 
sequences from the clone's library and make your own decision about that. 
However, remember that not all lone genomic fragments have had their function 
characterized, so it may be "real", no one knows for certain yet. The sequence 
is certainly not a gene in the traditional sense, but perhaps something else.

One method of finding sequences that overlap a certain region with a global 
footprint (instead of per exon == *matched bases*) is to create a custom track 
using the Table browser that only contains the txtStart and txtEnd and leave 
out the extra data columns that specify where the exons are (BED4 or similar 
http://genome.ucsc.edu/FAQ/FAQformat#format1). Using that file would cause the 
intron region to have a "hit" against the BED4 custom track file, since the 
entire genomic footprint of the sequence's alignment is considered (introns are 
not omitted).

Some Table browser help with examples (follow the links): 
http://genome.ucsc.edu/goldenPath/help/hgTracksHelp.html#TableBrowser 

Glad we could help,

Jennifer

------------------------------------------------ 
Jennifer Jackson 
UCSC Genome Bioinformatics Group 

----- "Chuangye" <[email protected]> wrote:

> From: "Chuangye" <[email protected]>
> To: "Jennifer Jackson" <[email protected]>, [email protected]
> Sent: Tuesday, November 10, 2009 7:36:12 PM GMT -08:00 US/Canada Pacific
> Subject: Re: [Genome] What differences between these ests
>
> Dear Dr Jackson ,
> 
> Thank you very much! That is to say, except EL584176, other ESTs in
> this
> region are introns corresponding to genome.
> 
> And I have one more question that other ESTs coordinates are
> following:
>  chr3    173240131       173448143       DA850742        0       +
> 173240131       173448143       0       6       124,34,105,76,77,127,
> 0,72804,72838,93823,187223,207885,  chr3    173240131       173448196
> DA864040        0       +       173240131       173448196       0     
>  6
> 124,34,105,76,77,180,   0,72804,72838,93823,187223,207885,  chr3
> 173240134       173448235       DA863440        0       +      
> 173240134
> 173448235       0       5       121,139,76,76,219,
> 0,72801,93820,187220,207882,  chr3    173240181       173448184
> CN289921        0       +       173240181       173448184       0     
>  5
> 74,139,76,77,168,       0,72754,93773,187173,207835,  chr3   
> 173241037
> 173448225       DB235484        0       +       173241037      
> 173448225
> 0       5       71,139,76,77,209,       0,71898,92917,186317,206979, 
> chr3
> 173241038       173448223       DA723804        0       +      
> 173241038
> 173448223       0       5       70,139,76,77,207,
> 0,71897,92916,186316,206978,  chr3    173247393       173448241
> DB076759        0       +       173247393       173448241       0     
>  5
> 38,139,76,77,225,       0,65542,86561,179961,200623,  chr3   
> 173312934
> 173451906       BI561806        0       +       173312934      
> 173451906
> 0       28
> 56,83,13,41,22,77,40,32,14,7,8,7,17,18,4,6,5,13,14,15,5,17,14,17,25,5,66,10,
> 0,57,21020,21033,21074,114420,135082,135122,135162,135176,135183,135191,135198,135215,135233,135237,135248,135253,135266,135286,135301,135307,138807,138846,138865,138890,138896,138962,
> chr3    173312938       173427430       BF992955        0       +
> 173312938       173427430       0       7       12,12,11,4,94,76,76,
> 0,15,27,38,42,21016,114416,  chr3    173312981       173448163
> AW748812        0       +       173312981       173448163       0     
>  8
> 5,4,6,15,63,76,77,147,  0,5,9,15,30,20973,114373,135035,  chr3
> 173327456
> 173427747       DB067370        0       +       173327456      
> 173427747
> 0       3       85,76,393,      0,6498,99898,
>  chr3    173327460       173451940       BG722524        0       +
> 173327460       173451940       0       5       81,76,77,244,197,
> 0,6494,99894,120556,124283,  chr3    173333995       173448120
> BE082404        0       -       173333995       173448120       0     
>  4
> 35,77,36,68,    0,93359,114021,114057, The coordinate of MER53 is
> chr3:173402247-173402431<http://genome.ucsc.edu/cgi-bin/hgTracks?hgsid=146499668&db=hg18&position=chr3%3A173402247-173402431>,
> why I intersect it with human ESTs used Table browser returned only
> EL584176 ? But if consider coordinates, these ESTs are all intersect
> with
> it. Could you tell me the reasons ? Thank you !
> 
> Best regards,
> 
> Chuangye
> 
> 
> 2009/11/10 Jennifer Jackson <[email protected]>
> 
> > Hello,
> >
> > The dark bar is an exon - this display is an indication that there
> is a
> > base level alignment at this position between the EST and the
> genome. The
> > rest of the data (other sequences) appears to support the idea that
> this is
> > instead an intronic region (no mRna/Est alignments at this location,
> but at
> > locations at one or either edge).
> >
> > Zoom out a few levels to see the big picture. Then try 10x to see
> where the
> > other sequence have exons.
> >
> > We hope this helps,
> > Jennifer
> >
> > ------------------------------------------------
> > Jennifer Jackson
> > UCSC Genome Bioinformatics Group
> >
> > ----- "Chuangye" <[email protected]> wrote:
> >
> > > From: "Chuangye" <[email protected]>
> > > To: [email protected]
> > > Sent: Monday, November 9, 2009 4:14:28 AM GMT -08:00 US/Canada
> Pacific
> > > Subject: [Genome] What differences between these ests
> > >
> > > Dear sir,
> > >
> > > Thank you for reading my Email!
> > >
> > > First, please set "chr3:173,402,247-173,402,431" in your
> > > "position/search"
> > > of UCSC Browser. Then set "full" of "Human EST" in "mRNA and EST
> > > Tracks".
> > > And "Refresh". OK, now you will see the picture of the attached
> > > figure. As
> > > you will see, a few ESTs with thin lines plus arrows but only one
> with
> > > thick
> > > line at the bottom with no arrows as upper ESTs. OK. My question
> is
> > > what the
> > > differences between the last one
> > > (EL584176<
> >
> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Search&db=nucest&term=EL584176&doptcmdl=GenBank&tool=genome.ucsc.edu
> > >)
> > > with others ?
> > >
> > > Thank you!
> > >
> > > Best wishes,
> > >
> > > Chuangye
> > >
> > > _______________________________________________
> > > Genome maillist  -  [email protected]
> > > https://lists.soe.ucsc.edu/mailman/listinfo/genome
> >
_______________________________________________
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