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lagan-2.0-7.fc15.i686.rpm

NOTE: Pairwise lagan has not changed in the 2.0 release

README.lagan for LAGAN aligner (Limited Area Global Alignment of Nucleotides) v1.1    
Author: Michael Brudno (brudno@cs.stanford.edu)                  04/02/2003

LAGAN was developed by 
Michael Brudno, Chuong Do, Michael F Kim and Serafim Batzoglouof the Dept of 
Computer Science at Stanford University, with assistance from many other people. 
See http://lagan.stanford.edu or contact lagan@cs.stanford.edu
for more information.

I Description

LAGAN is a global alignment tool. It does a Needleman-Wunsch alignment in a 
limited area of the matrix, determined during an anchoring phase.

The algorithm consists of 3 main parts, each documented in its own README file:

1. Generation of local alignments, using the CHAOS local alignment tool
2. Finding a monotonically increasing set of anchors from these local alignment, 
using the anchors program.
3. Doing global alignment in a limited area of thw NW matrix given the set of 
anchors (order tool).

lagan is the main executable that calls the three steps.

II Usage

1. Input
Lagan accepts requires two fasta files (first two arguments),reads gap and 
substitution parameters from the nucmatrix.txt file  and takes several 
optional command line options.

nucmatrix.txt -- This file has the substitution matrix used by lagan and the gap 
penalties. The gaps penalties are on the line immediately after the matrix,
the first number is the gap open, the second the gap continue.

-chaos "string" [default none]
The contents of string will be passed as arguments to CHAOS. See the CHAOS readme 
for details.

-order "string" [default none]
The contents of string will be passed as arguments to order. 

-recurfl "list of k-tuplets" [default: "(12,0,25,0),(13,1,25,0),(8,1,30,0)(7,1,30,0)"]
A list of (wordlength,number of degeneracies,score cutoff, rescoringcutoff) k-tuplets to be 
used in the recursive anchoring. See README.chaos for the meaning of these numbers.

-translate [default off] 
Use translated anchoring (homology done on the amino acid level). This is useful
for distant (human/chicken, human/fish, and the like) comparisons.

-bin [default off]
print the output in binary format, for use by the bin2bl tool, or VISTA

-mfa [default off]
print the output in Multi-FASTA format, for use by many standard tools

-rc [default off]
reverse-complement the second sequence before doing the alignment

-fastreject
Abandon the alignment if the homology looks weak. Currently tuned for human/mouse
distance, or closer. Please contact the authors for more details on this option.

2. Output

The output by default is in a blast like format, but you can use the -mfa or -bin 
options to save the results in multi-fasta, or binary format respectively. The 
binary format is a compact representation accepted by VISTA. There are some converters 
between the formats in the utils directory (see README.tools)