Can’t I get a hard-copy printout of my chromatogram file?


Termination of Sequencing Chromatogram Printout Services

Effective at the start of business on 01-Feb-05, we will no longer be printing DNA sequencing chromatograms.

These printouts have become increasingly obsolete and increasingly difficult to produce and to justify. The information they provide is poor and sometimes even misleading, since one frequently cannot judge the shape of the peaks and thus cannot ascertain the quality of the resulting base calls.

We STRONGLY encourage all of our clients to download and view the electronic chromatogram files. These are far and away superior to any hard-copy printouts in several respects:

  • Electronic chromats are cheaper and easier – for client and Core alike. Chromatogram viewing programs are easily available for most computer systems (often for free) and links to them are provided in the instructions page for our Download Results section.
  • Those viewing programs allow you to see even the smallest peaks, so any flaws (baseline noise, distorted shape, mis-spacing) are quickly detected. Printouts are inferior for assessing the validity of your basecalls.
  • Chromatograms can be utilized by a large variety of ancillary programs that help you to detect heterozygous peaks, identify point mutations and perform sequence matching or assembly. If you’re trying to eyeball your sequence, you’re just wasting valuable time.

I would be happy to help you with problems in downloading data; feel free to give me a call (at 4-8531), email me (, or simply stop by my office in NCRC B14, Rm 119.

And, as we always emphasize ….

If you aren’t looking at your chromatograms, the sequence is USELESS!