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Why does the BLA[S]T work?
Forget the T-similar words, now use only identities
2 sequences, 100 nucleotides each:
– What's the minimal sequence identity for which
there's a string of 3 consecutive identities?
0 identities, 100 mismatches:
67 identities, 33 mismatches:
but if seqs are 50% id, we'll detect it with prob. 99%
28% id -> we'll detect it with prob. 50%
– how is it calculated?
68st
?