Exon Coordinates Of Hg19 Genome Download

Question

[Neeraj]

Hi,

can any one help me in downloading the exon coordinates of all the genes present in the human genome hg19.

neeraj

[Neilfws]

Mostly, although that question asked for a Bioperl solution.

[Pierre Lindenbaum]

duplicate of Getting Genome Coordinates From Refseq Exon Mrna Position Data?

[Neilfws]

Mostly, all though that question asked for a Bioperl solution.

Answer 1

[Pierre Lindenbaum]

Using mysql:

mysql -u anonymous -h ensembldb.ensembl.org -P 5306 -D homo_sapiens_core_61_37f -A 
-e 'select S.stable_id,R.name,E.seq_region_start,E.seq_region_end,E.seq_region_strand from exon as E,seq_region as R,exon_stable_id as S where R.seq_region_id=E.seq_region_id and S.exon_id=E.exon_id'
+-----------------+------+------------------+----------------+-------------------+
| stable_id       | name | seq_region_start | seq_region_end | seq_region_strand |
+-----------------+------+------------------+----------------+-------------------+
| ENSE00002029850 | 5    |         94120533 |       94120602 |                -1 | 
| ENSE00002069321 | 4    |         17835922 |       17836146 |                 1 | 
| ENSE00002048418 | 5    |        123731640 |      123731794 |                -1 | 
| ENSE00001815244 | 6    |         13711167 |       13711796 |                -1 | 
| ENSE00001363151 | 2    |          1507720 |        1507851 |                 1 | 
| ENSE00001737796 | 1    |         40537122 |       40537924 |                 1 | 
| ENSE00001800436 | 2    |        165208630 |      165208733 |                -1 | 
| ENSE00001255746 | 10   |         93683822 |       93683847 |                 1 | 
| ENSE00001844789 | 14   |         74523609 |       74523683 |                 1 | 
| ENSE00002137765 | 8    |         17541844 |       17542051 |                -1 | 
(...)

Using UCSC & awk:

curl  -s "http://hgdownload.cse.ucsc.edu/goldenPath/hg19/database/knownGene.txt.gz" | gunzip -c |\
 awk '{n=int($8); split($9,S,/,/);split($10,E,/,/); for(i=1;i<=n;++i) {printf("%s,%s,%s,%s,%s\n",$1,$2,$3,S[i],E[i]);} }' 
uc001aaa.3,chr1,+,11873,12227
uc001aaa.3,chr1,+,12612,12721
uc001aaa.3,chr1,+,13220,14409
uc010nxq.1,chr1,+,11873,12227
uc010nxq.1,chr1,+,12594,12721
uc010nxq.1,chr1,+,13402,14409
uc010nxr.1,chr1,+,11873,12227
uc010nxr.1,chr1,+,12645,12697
uc010nxr.1,chr1,+,13220,14409
uc009vis.2,chr1,-,14362,14829

[Pierre Lindenbaum]

split($9,S,/,/) = split the column $9 ($9 is a comma-separated list of exonStarts) and put the result into the variable S. split($10,E,/,/) = split the column $10 ($10 is a comma-separated list of exonEnds) and put the result into the variable E.

[brentp]

@Pierre can you explain the awk command a little? it's hard for me to follow (but i already upvoted anyway)

[Pierre Lindenbaum]

and $8 is the number of exons

[brentp]

thanks Pierre, that helps.

[ines]

I have an issue with this... if I want only the exons of the main isoform, how can I extract them? because from this file there are some items that are the same, like uc001aaa.3,chr1,+,11873,12227 or uc010nxq.1,chr1,+,11873,12227

Answer 2

[Jorge Amigo]

several ways of doing this have been previously mentioned. the one I like the most because of its simplicity is using BioMart, selecting "martview", choosing the latest "Ensembl genes" database and the latest human dataset, and then selecting the attributes needed on the "structures" section (there you will have an "exon" subsection with "Exon Chr Start (bp)" and "Exon Chr End (bp)") without applying any filter at all.

[Neeraj]

Thanx Jorge it really helps me.Thanx a lot

[siyu]

Why the result of using Biomart is different from the result of using ensemble API ?

Answer 3

[Neilfws]

Search BioStar and you will find a number of solutions to this problem. Mostly they use BioMart, as outlined by Jorge, or the UCSC genome browser database tables, as described in the answer pointed to by Pierre.

One point: which set of exon coordinates do you want? There are several, depending on the gene prediction method used - e.g. UCSC, RefSeq or Ensembl transcripts.

If you start from UCSC tables, select "mammal, human, hg19" and then "Genes and Gene Prediction tracks" under "group", you will see the various gene models. Select one of those and choose "describe table schema" to see how exons are stored. Then go back to the main tables page, from where you should be able to download the exon data. This can also be done programmatically or through a SQL query to the UCSC MySQL server.