Scoring Matrix: Difference between revisions

From CoGepedia
Jump to navigation Jump to search
No edit summary
No edit summary
 
Line 4: Line 4:


Scoring matrices are used to determine the relative score made by matching two characters in a sequence alignment.  These are usually log-odds of the likelihood of two characters being derived from a common ancestral character.  There are many flavors of scoring matrices for amino acid sequences, nucleotide sequences, and codon sequences, and each is derived from the alignment of "known" [[homologous]] sequences.  These alignments are then used to determine the likelihood of one character being at the same position in the sequence as another character.
Scoring matrices are used to determine the relative score made by matching two characters in a sequence alignment.  These are usually log-odds of the likelihood of two characters being derived from a common ancestral character.  There are many flavors of scoring matrices for amino acid sequences, nucleotide sequences, and codon sequences, and each is derived from the alignment of "known" [[homologous]] sequences.  These alignments are then used to determine the likelihood of one character being at the same position in the sequence as another character.
For an excellent review of scoring matrices please see:
'''Where did the BLOSUM62 alignment score matrix come from?'''
Nature Biotechnology 22, 1035 - 1036 (2004)
''Sean R Eddy1'' (http://www.nature.com/nbt/journal/v22/n8/full/nbt0804-1035.html)

Latest revision as of 04:53, 22 February 2010

MatrixView of the Blosum 62 scoring matix
MatrixView of a codon scoring matrix generated from vertebrate genome alignments

Scoring matrices are used to determine the relative score made by matching two characters in a sequence alignment. These are usually log-odds of the likelihood of two characters being derived from a common ancestral character. There are many flavors of scoring matrices for amino acid sequences, nucleotide sequences, and codon sequences, and each is derived from the alignment of "known" homologous sequences. These alignments are then used to determine the likelihood of one character being at the same position in the sequence as another character.

For an excellent review of scoring matrices please see:

Where did the BLOSUM62 alignment score matrix come from? Nature Biotechnology 22, 1035 - 1036 (2004) Sean R Eddy1 (http://www.nature.com/nbt/journal/v22/n8/full/nbt0804-1035.html)