The COMET tool rapidly classifies HIV-2 nucleotide sequences into subtypes. You can submit your sequences either by pasting them in the form (b) or uploading them (a).

1.1Added bootstrap support levels (100 samples per sequence).2016-09-22
1.0Rewritten COMET in GO (Uses much less memory, faster; improved accuracy slightly).2016-09-18
0.2new HIV-2 thresholds, should slightly improve the results2012-06-11
0.1initial support for HIV-22011-03-17

Maximum size of each sequence (excluding fasta) 20000 characters

(a) upload the sequences in fasta format (you can compress the file with gzip, max. 8Mo (50MB)):

I confirm to use COMET only for non-commercial research purpose (*)

(b) paste the sequences in fasta format (try out example):

I confirm to use COMET only for non-commercial research purpose (*)

Privacy police:
The submitted sequences are deleted as soon the results have been generated.

If you use COMET, please cite:
Daniel Struck; Glenn Lawyer; Anne-Marie Ternes; Jean-Claude Schmit; Danielle Perez Bercoff. COMET: adaptive context-based modeling for ultrafast HIV-1 subtype identification. Nucleic Acids Research 2014; doi: 10.1093/nar/gku739 (full text)

Supplementary information:
HIV-2 training set

(*) The COMET-HIV and COMET-HCV services provided herein are "For non-commercial research use only". For all commercial uses, please contact our Exclusive Licensee, ABL SA ( at