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SPAdes error "Missing @SQ header"

Hi!

I am trying to do a de-novo assembly of a prokaryotic genome using SPAdes 3.5.0. I have been getting the following error

[samopen] no @SQ lines in the header.

[sam_read1] missing header? Abort!

I tried doing a subset of the reads and it worked. Thinking that it was a memory issue, I increased the memory allocation from 128GB to 350GB to give it ample memory but, unfortunately, it still didn't work with the full data set.

I think it has something to do with the mismatch correction (--careful) because the assembly was finished but the correction was aborted.

It also created a file named "@SQ SN:NODE_87368_length_231_cov_2.38312_ID_174735 LN:231" in the home directory (outside the spades folder), if that would be of any help.

Thanks!

assembly genome sequencing software error
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updated by Philipp Bayer Philipp Bayer • written by Angelo Victoria • Angelo Victoria

1 answer

In --careful, Spades uses BWA to align the reads back to the assembly in order to correct minor indels. This step generates the BAM files about which it complains.

There's a good chance that this breaks for your for some reason - could you post the whole STDOUT to pastebin.com or something like that? I have a hunch there's a tiny BWA error hidden somewhere, so that the BAM file isn't generated correctly, maybe there's a bogus read in the whole dataset, etc.

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written by Philipp Bayer Philipp Bayer

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