Code genotypes numerically Check this box to code the SNP genotypes numerically. Encoding is performed as follows, according to the allele frequencies in the Annotation SAS Data Set : Code Meaning 0 Homozygous for the major allele 1 Heterozygous 2 Homozygous for the minor allele Note : The Annotation SAS Data Set must contain the variable Allele_Frequencies . To Code Genotypes Numerically: Check the box.