NL genotype file ...

Genotypes for the 1,407 NL individuals. These are standard plink files (see http://pngu.mgh.harvard.edu/~purcell/plink/) where the first column gives a family id, the second column an individual id (in this case family id = individual id), the third and fourth columns are paternal and maternal IDs (here, left blank so that ids = 0 for both parents), column five has sex (1=male; 2=female; other=unknown) and finally column 6 phenotype (here all phenotypes = -9 for unknown). Columns 7 onwards contain genotype information for the SNPs listed (in order) in the .map file of the same name. ...