2. Example Amplicon Project Design and Analysis
:
2.5 Important Factors in the Assessment of New Variants
: 2.5.3 Bidirectional Support
2.5.3
Bidirectional Support
If your experiment was designed so that the Target has been sequenced from both directions, you can use that information to probe the validity of a potential Variant. This is only useful if the position of your Variant is in a region of the alignment that is covered by both forward and reverse reads; if the alignment position is only covered by reads of one direction you shouldn’t penalize the validity of the Variant for lack of bidirectional evidence.
If the specific Variant in question can be found in both forward and reverse reads, it is more believable as a true Variant. If the frequency of the Variant is similar in both directions, it is even more believable. If the frequency of the Variant is drastically different between the two directions, or if the Variant can only be found in one direction, you should be less likely to believe the Variant.
