I would be grateful if someone could take a quick look at these FASTQC results. This is rna-seq paired-end data. From the FASTQC manual, an unusual distribution seems to be suggestive of contamination and a shift in the curve is suggestive of a systematic bias. GC content distribution both pre-alignment and post-alignment are strange.
Samples are paired end, strand specific and % of mapped reads is above 95% for all the samples. There is no adapter content also.
What could be the problem?