SIFT Sequence provides SIFT predictions for a given protein FASTA sequence. This will take 10-15 min because we must search your protein sequence against a database to pick the related sequences. Before submitting to this website, try SIFT BLink , where you can get SIFT scores almost immediately. You can also submit your protein sequence and related sequences or aligned sequences if you already have them.

Results are deleted after an hour, so please save them!
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User Input

Enter your email address if you want the results through email :

Protein sequence

Name of file containing protein query sequence (fasta format).


Paste in your protein query sequence (Upload example) (fasta format).

Enter the substitutions of interest [format]:


Upload a file containing substitutions of interest [format]:


Select database to search:
Warnings for you predictions? Change this option

Median conservation of sequences
(between 0 and 4.32, we recommend between 2.75 and 3.25)

Remove sequences more than percent identical to query
This cleans out any polymorphic alleles (sequences in the database that are nearly identical to your protein but already containing the substitutions of interest). The contaminating sequences may cause the substitution to be predicted as tolerated.

Page last modified: May 2009