Hello everyone.

I am struggling to get good quality results on my Sanger sequencing reactions. I don't know the specific problem that I am facing. In a single order, most of the chromatograms acre clean, but some of them come with very low quality. Sometimes, the forward reactions come good and the reverse is unreadable.

I suspect that it could be a matter of wrong DNA product concentration. We don't purify the amplicons. Instead, we make a 1/50 dilution, which is cheaper and gives us good results. Anyways, it is the first time I work with sanger sequencing and I am unsure on how to interpret this results.

I attach some images so you can see some of the characteristic chromatograms I sometimes get. I'd appreciate it if you could give me some hint on what you think the problem could be in each one. Thank you so much.

Carlos.