Interaction Block Variables

Use this field to specify annotation variables to serve as additional filters for determining the SNPs to include in the interactions test.

Two-way interactions are formed by taking each possible pair of SNPs with the same value of the variable. A SNP can be included in multiple interactions by selecting multiple variables. SNPs with a missing value for the blocking variable are not used in creating interactions.

To Specify One or More Interaction Block Variables:

Specify the Annotation SAS Data Set.

All of the variables in the specified annotation data set are displayed in the Available Variables field.

Examine the list of available variables.

Highlight the variables to serve as block variables for the two-way interaction tests. To highlight multiple variables at once, hold down Ctrl while left-clicking.

Click to add the highlighted variables to the Interaction Block Variables field, as shown below: