Is there a way to identify which OTUs were merged at higher clustering thresholds?

Commands in mothur
1

Hello and thanks as always for Mothur’s many tools.

I’m trying to compare the clustering outputs across multiple thresholds (e.g., 3% vs 10%).

I’d like to generate a table that shows the hierarchy of OTU clustering across various thresholds (i.e., I want to know which 3% OTUs were merged together to create each of the 10% OTUs, or maybe just a select list of 10% OTUs).

Here’s an example of my desired output:

10% OTUs  3% OTUs
OTU0001  OTU0001, OTU0004, OTU0006
OTU0002  OTU0003,OTU0005,OTU0007,OTU0008,OTU0009,OTU0010
OTU0003  OTU0002,OTU0011
etc.

Does Mothur have a function that can do this sort of reverse-lookup?

I have some ideas for accomplishing this outside Mothur (using some combination of grep/sed and the .list file), but I’d rather not reinvent the wheel if it can be avoided.

Thanks in advance for any suggestions.

2

I think you are looking for the otu.hierarchy command, http://www.mothur.org/wiki/Otu.hierarchy.