Hey all this is not my usual haunt but I have a question.... I have been aligning my protein sequence , trying to find a homologue in a different species. The problem is its a bit fragmented and for a portion of it i have an e-value of e-139. What does this mean?
Thanks in advance,
Kami
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#2
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Why does a science forum not have pictures of mice and rats?
Posted 04 November 2009 - 08:02 AM
If I understand e-values correctly, e-values approaching zero are highly significant on long(er) sequences. Short sequences are more likely to have a greater number of matches in a database, some random, so the e-value is greater and significance is less.
42..."An immutable fixed-precision number of unlimited magnitude." <a href="http://en.wikipedia.org/wiki/Python_(programming_language)" target="_blank">http://en.wikipedia.org/wiki/Python_(programming_language)</a>, accessed 25June2009.
#3
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Posted 04 November 2009 - 08:11 AM
Low E values indicate high degrees of similarity -- they are the expected probability that the sequences are unrelated. An E value of 1 means that the match is probably random or chance. An E value of E-139 means almost absolute certainty that these are highly related sequences.
#4
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Posted 04 November 2009 - 08:42 AM
phage434, on Nov 4 2009, 04:11 PM, said:
Low E values indicate high degrees of similarity -- they are the expected probability that the sequences are unrelated. An E value of 1 means that the match is probably random or chance. An E value of E-139 means almost absolute certainty that these are highly related sequences.
Thank you so much guys! You may have just opened up my portal to working in a froggy world! (i needed to know if my gene is in xenopus... im not smoking anything weird)
