load.gwaa.data: function to load GWAA data

Description Usage Arguments Details Value Author(s) See Also

Description

Load data (genotypes and phenotypes) from files to gwaa.data object

Usage

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load.gwaa.data(phenofile = "pheno.dat", genofile = "geno.raw", 
		force = TRUE, makemap = FALSE, sort = TRUE, id = "id")

Arguments

phenofile

data table with phenotypes

genofile

internally formatted genotypic data file (see convert.snp.text to convert data)

force

Force loading the data if heterozygous X-chromosome genotypes are found in male

makemap

Make a consequtive map in case if map is provided chromosome-specifically

sort

Should SNPs be sorted in ascending order according to chromosome and position?

id

name of the column containing personal identification code in the phenofile

Details

The genofile must be the one resulting from convert.snp.text, convert.snp.ped, convert.snp.tped, or convert.snp.illumina (see documentation for these functions for the file formats).

The phenotype file relates study subjects with their covariate and outcome values. In the phenotypic data file, the first line gives a description of the data contained in a particular column; the names should be unique, otherwise R will change them. The first column of the phenotype file MUST contain the subjects' unique ID, named "id"; there should also be a column named "sex" and giving sex information (0 = female, 1 = male). Other columns in the file should contain phenotypic information. Missing values should be coded with "NA"; binary traits should have values 0 or 1. An example of few first lines of a phenotype file is as follows:

id sex age bt1 qt qt1

"289982" 0 30.33 NA NA 3.93

"325286" 0 36.514 1 0.49 3.61

"357273" 1 37.811 0 1.65 5.30

"872422" 1 20.393 0 1.95 4.07

"1005389" 1 28.21 1 0.35 3.90

This file tells us that, for example, person 325286 is female (0 in second column), and she has "1" (usually this means a "case") value for the trait "bt1", so on. Person 289982 has measurements only for sex, age and qt1, while other measurements are missing (NA, Not Available).

IDs are better kept in quotation (this would keep away the problem of e.g., leading zeros).

Value

Object of class gwaa.data

Author(s)

Yurii Aulchenko

See Also

save.gwaa.data, convert.snp.text, convert.snp.ped, convert.snp.tped, convert.snp.illumina


GenABEL documentation built on May 30, 2017, 3:36 a.m.