Illumina reads- noise in 1st 12nt

[crh]

Hi

We have Illumina paired end reads, and when we look at them w/ TrimGalore we see the the anomaly in the 1st 12-13 bases in the sequence content plot.
Are these adapters, and should they be trimmed?

thanks

charles

[GenoMax]

No trimming should be required. This is normal observation (specially for RNAseq data). See more info here: http://seqanswers.com/forums/showthr...c+bias&page=14

[crh]

Great - thanks for quick reply

Charles