DNA sequencing Chromatogram analysis

Question

[dipankar275]

What are the criteria for the differentiate between heterozygous peak and noise in DNA sequencing chromatogram?

Answer 1

[Denise CS]

I'd look at the height of the peaks. When it's simply noise they tend to be small bumps, whereas hets will be distinct peaks with 'similar' height. Check Interpretation of Sequencing Chromatograms and Identification of heterozygous point mutation events in DNA sequencing chromatograms for some nice images showing the differences between hets and noise.

[dipankar275]

Thanks, but how much height should be consider as a noise? is there any calculation for that?