General

How do I read my NGS report?
Wed, 23 Sep, 2020 at 2:12 PM
What is an ESV?
An ESV is an Exact Sequence Variant. The sequence represented by an ESV is generated from a denoising algorithm. Whereas OTUs are clusters of similar seque...
Mon, 5 Aug, 2019 at 4:01 PM
Why are you switching from reporting OTUs to ESVs?
We found that using ESVs reduces the number of items in results by 60%, e.g. 60% of the OTUs are a result of noise as opposed to likely being real. That mea...
Mon, 5 Aug, 2019 at 4:02 PM
Are there any drawbacks to ESVs?
The only thing we have seen so far is that some sequences that end in a long repeat of A (poly-A) are being separated as unique. We do not know if this is a...
Mon, 5 Aug, 2019 at 4:02 PM
Should I consider every ESV to be real?
We are agnostic on whether every sequence is real or not, but many low-abundance ESVs can still be excluded with justification. For example, if you are exam...
Mon, 5 Aug, 2019 at 4:02 PM
Do you have any references on ESVs?
The original ESV paper from Robert Edgar: https://www.biorxiv.org/content/10.1101/081257v1 Paper comparing ESVs and OTUs: https://peerj.com/articles/5364/ ...
Mon, 5 Aug, 2019 at 4:03 PM
The sample output says that my sample has DNA from a plant/insect/fish that I know is not at my site. Why?
Sometimes, the species actually is there. Often it isn’t, but more than likely some species closely related to species in the listed genus is found at your ...
Mon, 5 Aug, 2019 at 4:03 PM
Why do I not have data from some of my samples?
Some samples just do not amplify well – either do an insufficient amount of plant DNA in the sample or because it was difficult for us to get sufficiently c...
Mon, 5 Aug, 2019 at 4:03 PM
If the match is <100% can it still be a species in that genus?
Yes, but it is less likely to be a species in that genus. The OTU is based on a consensus sequence that represents a most probable sequence and a number of ...
Mon, 5 Aug, 2019 at 4:04 PM
What if there is no match between an OTU or ESV ID and anything in the library?
If there is no match in the library, this means that no species that have been sampled match the consensus sequences at some level of certainty. Generally, ...
Mon, 5 Aug, 2019 at 4:04 PM