| Code | Basis of Primary Map Locations |
|---|
| A1 | r6 sequence, flank seq alignment |
| A2 | r6 sequence, FRT progenitors |
| A3 | r6 sequence, attP site |
| A4 | r6 sequence, gene location |
| A5 | r6 sequence, restriction frag or sequencing |
| A6 | r6 sequence, clone sequence alignment |
| A7 | r6 sequence, author statement |
| A10 | r6 sequence, homologous recombination |
| A16 | r6 sequence, progenitor insertion |
| A17 | r6 sequence, author statement |
| A18 | r6 sequence, multiple types |
| C17 | r6 arm, author statement |
| D4 | observed cytology, gene location |
| D12 | observed cytology, polytene chr banding |
| D13 | observed cytology, polytene chr in situ |
| D17 | observed cytology, author statement |
| D18 | observed cytology, multiple types |
| D19 | observed cytology, segregation |
| F1 | r6 computed cytology, flank seq alignment |
| F4 | r6 computed cytology, gene location |
| H4 | r5 computed cytology, gene location |
| H5 | r5 computed cytology, restriction frag or sequencing |
| H8 | r5 computed cytology, author statement |
| H15 | r5 computed cytology, aberration location |
| H17 | r5 computed cytology, author statement |
| K5 | r3 computed cytology, restriction frag or sequencing |
| N19 | chromosome, segregation |
| U0 | unknown location, not applicable |