Filter to Exclude Chromosomes Use this option to specify a list of chromosome IDs that you want to exclude from the SAS data set generated by this import engine.. To Specify chromosomes to Exclude: Type the number or letter designation for each chromosome to be excluded within the text box. The chromosome IDs must be separated by a white space. For example, type X Y M 10 (as shown below) to drop chromosomes X, Y, M and 10 from the resulting SAS data set.