You should use -out=psl (the default) if you want your results to match
the web blat (hgBlat) closer.

A Psl is a full alignment containing chained-together-exons
and gaps with splice-junction-adjusted.

Blast output only contains exons with no gaps since that is all
that the real BLAST program creates.

When you chose blast output, the best single exon was on chr3,
however the best full psl alignment is on chr7.

QUERY           SCORE START  END QSIZE IDENTITY CHRO STRAND 
START    END      SPAN
---------------------------------------------------------------------------------------------------
NM_005692.3     2235     1  2250  2262 100.0%     7   - 
150535856 150555250  19395

NM_005692.3     1687    50  1982  2262  93.6%     3   + 
88448934  88450861   1928

If you look at NCBI for NM_005692.3
  http://www.ncbi.nlm.nih.gov/nuccore/27881504?report=GenBank
it says that this mRNA is located on chr7.

If you look at this one huge exon on chr3,
it appears to be a processed-pseudogene.

I offer my limited and simplistic understanding
of pseudogenes:
The introns are removed by splicing and then
the now "processed" mRNA gets converted 
by some reverse transcriptase to DNA
and then re-integrated into chr3.
There may be other mechanisms that create
processed pseudogenes as well.
Some pseudogenes are expressed and retain expression,
some lose expression, and some never had it.
Unexpressed pseudogenes are more prone to decay
via random mutation.  Some pseudogenes turn into
real functional genes and may evolve new uses.

You can see that with the pseudo-gene tracks
in the group Genes and Gene Prediction Tracks.

-Galt


On Wed, 15 Jul 2009, zhidong zhu wrote:

> Dear UCSC Team:
>
> I build your blat system locally. When I run gfClient, I obtained a
> different result from what I obtained from your web. How can I obtain the
> identical result like your web supported.
> The different points:
>   1. the first match result: my local result chromosome is "chr3", while
> your web result is "chr7"
>   2. not perfect match occurred in my local result, while your web result
> only shows 16 block perfectly match the chr7.
>
> My command:
>  ./gfClient 10.4.0.58 17779 ./ test_seq   test_blast8    -t=rna -q=dna
> -out=blast8
>
> The content of test_blast8 is below:
>   gi|27881504|ref|NM_005692.3|    gi|16|ref|chr3| 93.44   1935    118     3
> 50      1982    88448934        88450861        0.0e+00 3384.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  271     0       0
> 1980    2250    150536126       150535856       2.5e-152        535.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  213     0       0
> 266     478     150553007       150552795       1.8e-116        416.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  204     0       0
> 1642    1845    150543101       150542898       3.4e-112        402.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  196     0       0
> 70      265     150554519       150554324       4.3e-107        385.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  183     0       0
> 479     661     150552133       150551951       1.3e-99 360.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  172     0       0
> 662     833     150551868       150551697       1.7e-93 340.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  134     0       0
> 1846    1979    150542210       150542077       1.5e-70 263.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  129     0       0
> 1513    1641    150543751       150543623       5.7e-67 252.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  120     0       0
> 1129    1248    150546892       150546773       2.6e-62 236.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  111     0       0
> 1339    1449    150546210       150546100       1.6e-56 217.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  103     0       0
> 930     1032    150549699       150549597       2.0e-51 200.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  96      0       0
> 834     929     150550635       150550540       7.0e-48 188.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  96      0       0
> 1033    1128    150547178       150547083       1.0e-47 188.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 85.12   121     18      0
> 1843    1963    71206996        71207116        1.3e-45 181.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 86.21   116     16      0
> 1727    1842    71206141        71206256        1.8e-45 180.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  90      0       0
> 1249    1338    150546669       150546580       6.7e-44 175.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  69      0       0
> 1       69      150555250       150555182       1.5e-32 137.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 100.00  63      0       0
> 1450    1512    150544048       150543986       2.7e-28 123.0
> gi|27881504|ref|NM_005692.3|    gi|20|ref|chr7| 93.75   32      2       0
> 1690    1721    71206102        71206133        8.0e-09 58.0
>
>
> zhidong zhu
> national biochip engineering center at shanghai.
>
>
>
>
> _______________________________________________
> Genome maillist  -  [email protected]
> https://lists.soe.ucsc.edu/mailman/listinfo/genome
>
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