FlyBase:Maps
Genetic, Cytological and Genomic Map Coordinates for D. melanogaster Genes
FlyBase offers a downloadable spreadsheet that lists the genomic coordinates, cytological (polytene band) position and genetic map position for all annotated D. melanogaster genes. Information for each chromosome arm is available on a separate tab of the spreadsheet. For both cytological and genetic map positions, we report both experimentally determined values reported in the literature as well as FlyBase computational estimates. For genetic map positions, we also provide an alternative computational estimate based on the mapping of millions of SNPs from thousands or recombination events Comeron et. al., 2012.
D. melanogaster Chromosome Maps
Table 1. The original illustrations of D. melanogaster polytene chromosomes by Bridges and Slizynski.
| Species | Chromosome | Muller Element | References | File |
|---|---|---|---|---|
| D. melanogaster | X | A | Bridges 1938, Bridges 1935 | Dmel_X_Bridges.png |
| D. melanogaster | 2L | B | Bridges 1942, Bridges 1935 | Dmel_2L_Bridges.png |
| D. melanogaster | 2R | C | Bridges and Bridges 1939, Bridges 1935 | Dmel_2R_Bridges.png |
| D. melanogaster | 3L | D | Bridges 1941, Bridges 1935 | Dmel_3L_Bridges.png |
| D. melanogaster | 3R | E | Bridges 1941, Bridges 1935 | Dmel_3R_Bridges.png |
| D. melanogaster | 4 | F | Slizynski 1944 | Dmel_4_Slizynski.png |
Table 2. The original electron micrographs of D. melanogaster polytene chromosomes by Lefevre. High magnification electron micrographs of individual D. melanogaster polytene chromosome bands are available from Saura, Saura and Sorsa, University of Helsinki. These electron micrographs offer an alternative reference for checking polytene band references.
| Species | Chromosome | Muller Element | References | File |
|---|---|---|---|---|
| D. melanogaster | X | A | Lefevre 1976 | Dmel_X_Lefevre.png |
| D. melanogaster | 2L | B | Lefevre 1976 | Dmel_2L_Lefevre.png |
| D. melanogaster | 2R | C | Lefevre 1976 | Dmel_2R_Lefevre.png |
| D. melanogaster | 3L | D | Lefevre 1976 | Dmel_3L_Lefevre.png |
| D. melanogaster | 3R | E | Lefevre 1976 | Dmel_3R_Lefevre.png |
| D. melanogaster | 4 | F | Lefevre 1976 | Dmel_4_Lefevre.png |
Table 3. Annotated D. melanogaster chromosome maps that combine illustrations and electron micrographs with annotation of the genomic, genetic and cytological positions indicated for select genes. Note that for the Y chromosome, the micrograph shown is of a prometaphase mitotic chromosome. Note also that large genome assembly gaps are not depicted in GBrowse, and so Y chromosome genes look closer together than they really are.
| Species | Chromosome | Muller Element | References | File |
|---|---|---|---|---|
| D. melanogaster | X | A | Dmel_X.png | |
| D. melanogaster | 2L | B | Dmel_2L.png | |
| D. melanogaster | 2R | C | Dmel_2R.png | |
| D. melanogaster | 3L | D | Dmel_3L.png | |
| D. melanogaster | 3R | E | Dmel_3R.png | |
| D. melanogaster | 4 | F | Dmel_4.png | |
| D. melanogaster | Y | Kennison 1981, Hazelrigg et al., 1982, Gatti and Pimpinelli 1983 | Dmel_Y.jpg | |
| D. melanogaster | M | Dmel_M.png |
Drosophila Chromosome Maps
The table below lists chromosome map images available for various non-melanogaster Drosophila species. Micrographs are from Schaeffer et al., 2008. Related chromosomes in different Drosophila species may have different names and even a different organization. As such, we list the Muller element correspondence for each chromosome arm, which represents the common chromosome arms among Drosophila species: A, B, C, D, E and F. These relationships are depicted in this Muller Element Arm Synteny Table, which also incorporates a view of the phylogenetic relationships of the species, their standard chromosomal numbering and the corresponding Muller element.
Take note:
- There is not a simple one-to-one correspondence for all of the species chromosome arms and a single Muller element.
- Species-specific chromosome images are not available for species closely related to D. melanogaster (D. simulans, D. sechellia, D. erecta and D. yakuba) - instead, schematic depictions of chromosomes in these species are shown next to images for homologous D. melanogaster chromosomes (with inversions relative to the D. melanogaster chromosome indicated).
- For the D. mojavensis third chromosome (Muller B element) image, the micrograph (bottom) is from the sequenced Santa Catalina strain that is homozygous for the f2=MU inversion, but the drawing (center, originally from Ruiz et al., 1990) does not depict this inversion. See Delprat et al., 2014 for details.
Table 4. Drosophila Polytene Chromosome Maps.
