If you use IEM, watch out for A027

hoytpr

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#1

If you use IEM, watch out for A027

01-09-2018, 03:03 PM

We just completed a sequencing run that used the Illumina A027 (or the AR027) index on one of the samples. Setting it up on the NEWER version of IEM incorrectly assigns it the sequence of ATTCTT, but the correct sequence, (and the one assigned by the older IEM software) is ATTCCT.

Luckily the Bcl2Fastq detected the 99+% "one basepair mismatch barcode" and all the samples sorted properly, but y'know, a bug's a bug.

Last edited by hoytpr; 01-09-2018, 03:20 PM. Reason: added index number
Tags: a027, iem, index sequence, one basepair mismatch
GenoMax

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01-10-2018, 04:03 AM

Hopefully you have reported this back to Illumina so IEM can be fixed.
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hoytpr

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#3

01-10-2018, 06:10 AM

Yes, and it was confirmed yesterday to be a bug in IEM 1.14 and 1.15 (just released), but not in 1.11. I have not tested 1.12, or 1.13.
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If you use IEM, watch out for A027

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