Thanks a lot Brooke for your detailed answer, everything is clear to me now
Mali

On Wed, Jul 6, 2011 at 10:36 PM, Brooke Rhead <[email protected]> wrote:

> Hi Mali,
>
> The answer to your question is more complicated than I thought it would be.
>  The sacCer2 assembly at UCSC and the EF2 assembly at Ensembl are *almost*
> the same build.
>
> Ensembl's site says that the EF2 genome is from March 2010:
> http://apr2011.archive.**ensembl.org/Saccharomyces_**
> cerevisiae/Info/Index?db=core<http://apr2011.archive.ensembl.org/Saccharomyces_cerevisiae/Info/Index?db=core>
>
> The UCSC sacCer2 genome "is based on sequence dated June 2008 in the
> Saccharomyces Genome Database (SGD)":
> http://genome.ucsc.edu/cgi-**bin/hgGateway?&db=sacCer2<http://genome.ucsc.edu/cgi-bin/hgGateway?&db=sacCer2>
>
> However, there are some tiny differences between the two genome builds.
>  One of our engineers summed it up:
> ---
> The Ensembl EF2 sequence is different from UCSC sacCer2 sequence
> in six bases on two chromosomes. UCSC has one extra T in chrX
> and one more C and T, and three less G on chrXIV
>
> EF2 has:
> #seq len A C G T
> X 745741 231168 142294 143873 228406
> XIV 784334 241562 151655 151389 239728
>
> UCSC sacCer2 has these two chromosomes as:
> #seq len A C G T
> chrX 745742 231168 142294 143873 228407
> chrXIV 784333 241562 151656 151386 239729
> ---
>
> So, sacCer2 and EF2 are slightly different.  The gene coordinates in UCSC's
> Ensembl Genes track are downloaded directly from Ensembl.  Since they are
> given in Ensembl's EF2 coordinates, some of the annotations on chromosomes
> 10 and 14 are off by one base when they are displayed on the sacCer2 genome
> browser.
>
> You can see some examples of the problem on chromosomes 10 and 14 by
> turning on both the "SGD Genes" (created from data downloaded from SGD on
> January 30, 2009; see: http://genome.ucsc.edu/cgi-**
> bin/hgGene?hgg_do_kgMethod=1<http://genome.ucsc.edu/cgi-bin/hgGene?hgg_do_kgMethod=1>)
> and "Ensembl Genes" (updated with each Ensembl update -- currently on
> version 62) tracks in the Genome Browser.  For instance:
>
> SOR1
> chrX:736035-737108 sgdGene
> chrX:736034-737107 ensGene
>
> PAU6
> chrXIV:781918-782280 sgdGene
> chrXIV:781919-782281 ensGene
>
> I hope this helps you decide what data to work with.  If you have further
> questions for us, please feel free to write back to [email protected].
>
>
> --
> Brooke Rhead
> UCSC Genome Bioinformatics Group
>
>
>
> On 06/30/11 11:37, mali salmon wrote:
>
>> Thanks Brooke
>> So I just want to be sure that I use the same build for the sequences and
>> the annotation. I use sacCer2 genome I downloaded from your ftp site, and
>> a
>> gtf file of annotated ensembl genes from the table browser (for sacCer2).
>> Is
>> this OK? do the genome and the annotation are of the same build?
>> What confuses me is that there were no difference in the genomic locations
>> for ensembl genes downloaded from the table browser (sacCer2 June 2008),
>> and
>> those for EF2 from ensembl site. I thought that sacCer2 and EF2 are two
>> different builds of the genome. Am I wrong?
>> Thanks for your help
>> Mali
>>
>> On Thu, Jun 30, 2011 at 7:25 PM, Brooke Rhead <[email protected]> wrote:
>>
>>  Hello Mali,
>>>
>>> I see what you are talking about now.  Thank you for clarifying.
>>>
>>> I confirmed with our engineers that the "(lifted to sacCer2 from Ensembl
>>> version EF 2)" comment was only applicable to version 59 of Ensembl Genes
>>> on
>>> sacCer2.  Versions 60, 61, and 62 are identical to Ensembl. The comment
>>> was
>>> incorrect and has been removed.
>>>
>>> Thank you for alerting us to this error, and sorry for the confusion!
>>>
>>>
>>> --
>>> Brooke Rhead
>>> UCSC Genome Bioinformatics Group
>>>
>>>
>>> On 06/29/11 22:01, mali salmon wrote:
>>>
>>>  Dear Brooke
>>>> Thanks for your reply. I'm not on a mirror site, but using the main UCSC
>>>> site.
>>>> In order to download the gtf file I went to the table browser, and chose
>>>> the
>>>> following:
>>>> genome: S.cerevisiae
>>>> assembly: June 2008, SGD/sacCer2
>>>> group: Ensembl genes
>>>> track: ensGene
>>>> output format: GTF
>>>> When I click on the "Describe table schema" link I see:
>>>> "Schema for Ensembl Genes - Ensembl Genes *(lifted to sacCer2 from
>>>> Ensembl
>>>> version EF 2*)"
>>>> Mali
>>>>
>>>>
>>>> On Wed, Jun 29, 2011 at 11:00 PM, Brooke Rhead <[email protected]>
>>>> wrote:
>>>>
>>>>  Hi Mali,
>>>>
>>>>> Can you be more specific about how you downloaded the file from the
>>>>> Table
>>>>> Browser?  I only see regular (not lifed) version 62 Ensembl genes on
>>>>> the
>>>>> UCSC sacCer2 browser.
>>>>>
>>>>> Were you by any chance on a mirror site, and not on
>>>>> http://genome.ucsc.edu/?
>>>>>
>>>>> --
>>>>> Brooke Rhead
>>>>> UCSC Genome Bioinformatics Group
>>>>>
>>>>>
>>>>>
>>>>> On 06/29/11 03:15, mali salmon wrote:
>>>>>
>>>>>  Dear Sir/Madam
>>>>>
>>>>>> I have downloaded a gtf file for yeast ensembl genes from the ucsc
>>>>>> table
>>>>>> browser.
>>>>>> According to the description of the table, the locations were "lifted
>>>>>> to
>>>>>> sacCer2 from Ensembl version EF 2."
>>>>>> However, when I compare the locations I get to those from ensembl gtf
>>>>>> file
>>>>>> I
>>>>>> downloaded from ensembl ("Saccharomyces_cerevisiae.******EF2.
>>>>>> 62.gtf), I see that there is no difference.
>>>>>> How this could be? I suppose there are some changes between the two
>>>>>> builds
>>>>>> Looking forward to your reply
>>>>>> Thanks
>>>>>> Mali
>>>>>> ______________________________******_________________
>>>>>> Genome maillist  -  [email protected]
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>>>>>> >
>>>>>> <https:**//lists.soe.ucsc.edu/**mailman/**listinfo/genome<http://lists.soe.ucsc.edu/mailman/**listinfo/genome>
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>>>>>> >
>>>>>>
>>>>>>
>>
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