All sequence data subset facilities are accessible through the Export Data command in the Sequence Data Explorer. To write 4-fold degenerate sites to a file, highlight the 4-fold degenerate sites on the screen and then select Export Data. In that command, choose to write only the highlighted sites. For example, if you select to write only the third codon positions, all 4-fold degenerate sites found in the third codon positions will be written to the file.