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Sequence Assembly and Alignment

The first step in validating the quality of the Barcode data in a project is certifying that the sequences have been properly assembled, edited, and aligned. In order to do that, users will need to have some basic knowledge about sequence editing and what to look for when editing sequences.

This document provides only basic information on the process of sequence editing - for an advanced understanding on how to properly assemble and edit DNA sequences, using more specific sources is recommended.

A trace file, also called a chromatogram, is a combination of a graphical representation of a DNA sequence and the matching nucleotide interpretation. Each chromatogram is composed of colour-coded peaks with each colour corresponding to one nucleotide. They are automatically supplied by DNA sequencing programs.

good quality trace Good quality trace file

In order to ensure the accuracy of sequences, it is important to manually check the quality of the traces. Errors are commonly found at the beginning and the end of the trace file where the signal intensity is weakest.