Video talks on 16S data analysis posted.

URMAP ultra-fast read mapper posted (paper).

~20% of taxonomy annotations in SILVA and Greengenes are wrong (paper).

Taxonomy prediction is <50% accurate for 16S V4 sequences (paper).

97% OTU threshold is wrong for species, should be 99% for full-length 16S, 100% V4 (paper).

Ambiguous cluster assignment

If an input sequence has similarity above the identity threshold with to two different centroids, then the cluster assignment is ambiguous, as illustrated in the figure. In general, this issue cannot be avoided in centroid-based clustering.