QTL Test Step in cM (1-D Genomewide Scan) Use this drop-down menu to specify the distance (in cM) between two putative QTL testing points. This value will be used solely in the search for two-interaction between QTL already in the model and putative QTL in the genomic testing grid (1-D search for interaction) To Specify the Distance between QTLs: Select the desired distance using the drop-down menu.