SAM file from gsMapper: wrong positions¿?

[CPCantalapiedra]

Hi,

I am using DataAnalysis_2.6_All_20110523_1850 gsMapper to map some reads to the sequences they come from, so that I know the original position of the reads.

The thing is that for some sequences starting with an homopolymer the BAM file outputs a wrong position while in 454PairAlign it is correct. I think is happening something like:

BAM file:
AAAAAA-----------------------AGTCGGCTAGCGATGCGA
AAAAAAAAAAAAAAAAAGTCGGCTAGCGATGCGA
454PairAlign
______________AAAAAAAGTCGGCTAGCGATGCGA
AAAAAAAAAAAAAAAAAAGTCGGCTAGCGATGCGA

I have searched for this discussion but haven't found anything. Has anyone information about this issue? I am about to write Roche about this bug, cause could be really error prone when working with sequences without knowledge of their actual position, when using the BAM file. But I wanted to ask here before to do that cause likely I am missing something.

thank you

[flxlex]

I got the impression that SAM support for newbler was kind of experimental still. So, please go ahead and report a bug to Roche/454!

[CPCantalapiedra]

I have reported it and waiting for appropiate answer. Should I be confident about other files from gsMapper, as 454ReadStatus.txt?

This is from 454ReadStatus.txt
gi|326526112|dbj|AK362029.1|:2996:fwd Full 99 100 gi|326526112|dbj|AK362029.1| 2927 3536 +

This is from 454PairAlign.txt
>gi|326526112|dbj|AK362029.1|:2996:fwd, 1..544 of 544 and gi|326526112|dbj|AK362029.1|, 2997..3536 of 3799 (538/546 ident)


Again, this is for 454PairAlign.txt

>gi|326514771|dbj|AK368544.1|:55:fwd, 1..423 of 423 and gi|326514771|dbj|AK368544.1|, 56..477 of 1340 (422/423 ident)

And this is from 454ReadStatus.txt

gi|326514771|dbj|AK368544.1|:55:fwd Full 100 100 gi|326514771|dbj|AK368544.1| 29 477 +

And from SAM file:
gi|326514771|dbj|AK368544.1|:55:fwd 0 gi|326514771|dbj|AK368544.1| 29 100 5M27D370M1I47M * 0 0 AAAAACCAACCAAATCCTAACTCTGCAACTGCAACTCACCTTGCTTGTCCCCGTTGCCGGCGGCAGCGTCGCCGCCGCGACCGTATCCCTTCGCCTGCGGCGCGAGGACCTGCCCTTTACCTCCGCGCCAGATACGTGCGGCTTGGCCGTGCCAACGCGTTCTCGGGAGTTTTGGATCTTGGTTGTCCTCGTAGCCGCCCCCGCATCCCTATTGCTCGTGCAGTCGTGCTCCTCCAAATTCGCCGGCTGCCGGTGTCCCGGCTCGGCCACAGCCCGCAGTAGGACCATGGTGCTAGAACAGAAAGGAGAAACGTCCAGTGGCATGTATACTTACAAGCATCGTGGTGACAAGGGAGTTGATATCCATGAGATTTTTCGTTAAGAAGAGCAGAACCCGTGTTCTGCTGTCGTATACTGGACTCA AAAA44444@@@@??999AAAAAA99AAAA@@AA?@@@A@A@>>??@@@@=A4444@??@??<<@???@@??@@===@00@@?<>>8<?9;;;>>?9??>?;??>6><?>>:??>>:::;;;>==>??:><??>>9>>:8>>>>>:6699==>=>????>>>>??>>?<<<>>((((??:>>????>><>??>>>>><??=/////5->>;;;>:??>>8?><?>>=>>=>>==>>&>>;;;77>-====><5>>>>=>=888=====<<//*>=>999==<.5;>>=99============;==33399==888;=====;===<=:<<;<<=;;<<33<4<*<<:<<<:4<;;555;8;;;8<;<;;<;<27:#####:90099:99::8:7888444:9:99658888886777578557

I hope someone can confirm I am missing some point.