FaST-LMM-2.07
FaST-LMM (Factored Spectrally Transformed Linear Mixed Models) is a program for performing genome-wide association studies (GWAS) on large data sets. It runs on both Windows and Linux system, and has been tested on data sets with over 120,000 individuals. FaST-LMM is described more fully in the paper at http://www.nature.com/nmeth/journal/v8/n10/abs/nmeth.1681.html. [Description from the Codex page.]
Command Line Usage
FaST-LMM has a great many options; see user-manual.pdf.
Many of the standard options for FaST-LMM ask for prefixes of filenames instead of actual filenames. A separate wrapper has been developed to handle those types of options. The wrapper adds an additional option, --folder=<foldername>, and that folder name will then be prepended automatically to the FaST-LMM options that require a name prefix, specifically -file, -tfile, -bfile, -dosage, -pheno, -filesim, -bfilesim, -tfilesim, -dosagesim, -sim, and -covar will be altered.
Test Data
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Test data for this app appears directly in the Discovery Environment in the Data window under Community Data -> iplantcollaborative -> example_data -> fastlmm -> input. |
Input Files
- SNP data to be tested. (required)
There three possible input formats, only one may be used at a time. Make sure to follow the directions on the application when entering input data. For example, if using the regular fileset (.map/.ped) then enter the inputs into .map and .ped box respectively, leaving all other input boxes empty. If using transposed fileset (.tfam/.tped) then enter inputs in the labeled .tfam and .tped boxes, leaving the other boxes empty . In ADDITION the user must go to the parameters section and check the box saying 'Transposed files are inputs'. The same thing must be done when entering the binary fileset.
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Phenotype data. (optional) Uses the PLINK alternative phenotype. Includes at least three columns, family ID, individual ID, and phenotype value. Missing value as default is -9 but it can be changed. The first two fields create a unique ID which matches the first two SNP files. Optional header row allowed, and any number of phenotypes can be specified in different columns. An example with two phenotypes from the documentation with optional header:
No Format FID IID MyPheno YourPheno 1 IND0 2 3.05043 1 IND1 2 1.72797 1 IND2 -9 4.19592 1 IND3 2 3.4492 1 IND4 1 -8.99843 1 IND5 1 -0.768613 1 IND6 2 6.73734 ...
Set of covariates (optional). Must have at least three tab-delimited columns: family ID, individual ID, and covariate value, and may have any number of covariate values. The same missing value signifier from the third file must be used. Example from the documentation; the file should not have a header row:
No Format 1 IND0 1 1 IND1 1 1 IND2 1 1 IND3 1 1 IND4 1 1 IND5 -9 1 IND6 1 ...
Direct genetic similarities file (optional). The file must be tab-delimited and have both row and column labels for individual IDs; the value of the top-left corner of the file (first column header) should be “var”. Example from the documentation:
No Format var IND0 IND1 IND2 IND3 ... IND0 1.0 0.5 0.5 0.25 ... IND1 0.5 1.0 0.5 0.5 ... IND2 0.25 0.5 1.0 0.5 ... ...
Output Files
The expected output from the command line:
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SNP | The rs# or SNP identifier for the SNP tested. Taken from the PLINK file. |
Chromosome | The chromosome identifier for the SNP tested or 0 if unplaced. Taken from the PLINK file. |
GeneticDistance | The location of the SNP on the chromosome. Taken from the PLINK file. Any units are allowed, but typically centimorgans or morgans are used. |
Position | The base-pair position of the SNP on the chromosome (bp units). Taken from the PLINK file. |
Phenotype | [under --verboseOut] The name of the phenotype as specified in the header of the phenotype file. NoName means that no header row was specified. |
Pvalue | The p-value computed for the SNP tested |
Qvalue | The q-value computed for the SNP tested estimated from the p-values of all testSNPs in the PLINK file using the procedure of Benjamini and Hochberg |
N | The sample size or number of individuals that have a been used for this analysis |
NumSNPsExcluded | [under --excludeByGeneticDistance] |
IndexExclusionStart | [under --excludeByGeneticDistance] |
DOF | [under --verboseOut] The degrees of freedom of the statistical test |
NullLogLike | The log likelihood of the null model |
AltLogLike | The log likelihood of the alternative model |
SnpWeight | The fixed-effect weight of the SNP |
SnpWeightSE | The standard error of the SnpWeight |
WaldStat | The Wald stat of the SnpWeight |
NullLogDelta | The ratio between the residual variance and the genetic variance on the null model |
NullGeneticVar | The genetic variance on the null model |
NullResidualVar | The residual variance on the alternative model |
NullBias | The offset term in the null model |
LogDelta | [under --verboseOut] The ratio between the residual variance and the genetic variance on the alternative model |
geneticVar | [under --verboseOut] The genetic variance on the alternative model |
ResidualVar | [under --verboseOut] The residual varianceon the alternative model |
NullBias_ | [under --verboseOut] The offset term in the alternative model |
SNPIndex | The column index of the SNP tested in the PLINK file starting at 1 |
SNPCount | The number of SNPs tested |
Rounding Issues
FaST-LMM sometimes shows slightly different results on different platforms due to rounding issues. The example data available in the Discovery Environment was generated in the Discovery Environment and will likely vary in a very minor way from results run locally.
Tool Source
Binary | |
Source | |
Version | 2.07 |
User Guide | |
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