TABLE 1.
Difference in number of retrotransposon-related sequences between sex chromosomes and autosomes
| Source of fragments | n | TE | χ2 | P-value |
|---|---|---|---|---|
| M. violaceum | ||||
| A1 and A2 sex chromosomes | 499 | 73 | 7.46 | <0.01 |
| Autosomes | 185 | 12 | ||
| H. sapiens | ||||
| X chromosome | 214 | 55 | 25.37 | <0.01 |
| Autosomes | 208 | 18 | ||
| M. musculus | ||||
| X chromosome | 180 | 50 | 8.11 | <0.01 |
| Autosomes | 177 | 27 | ||
| S. cerevisiae | ||||
| Chromosome 3 | 396 | 15 | 0.32 | 0.57 |
| Chromosomes 1, 2, 4–16 | 391 | 12 | ||
| C. elegans | ||||
| X chromosome | 399 | 5 | 0.00 | 0.98 |
| Autosome | 401 | 5 | ||
| D. melanogaster | ||||
| X chromosome | 370 | 7 | 1.64 | 0.20 |
| Autosomes | 379 | 13 |
Sequence similarity to retrotransposons was determined by a BLASTx search of the nr databases of the NCBI at the National Institutes of Health. n, number of random DNA fragments per source; TE, number of retrotransposon-related sequences. χ2 tests had 1 d.f. Chromosome 3 of Saccharomyces contains the MAT locus determining mating compatibility, but is otherwise similar to an autosome.