Frequency of the major classes of interspersed repeated elements (in term of percent of the sequence length) in the autosomes, the X chromosome, in the Xic region taken as a whole and in introns of genes located in the Xic region
| Length (kb analyzed) | LINE (%) | SINE (%) | LTR (%) | DNA (%) | Total (%) | ||
| Mouse | Autosomes[i] | 223,057 | 10.5 | 9.4 | 6.9 | 0.5 | 27.4 |
| X chromosome[i] | 10,000 | 16.2 | 9.1 | 6.5 | 0.7 | 32.6 | |
| Xic region | 714 | 14.5 | 14.5 | 8.5 | 0.3 | 37.9 | |
| Xistintrons | 9 | 0.0 | 10.2 | 0.0 | 0.0 | 10.2 | |
| Other introns[iii] | 190 | 17.2 | 13.2 | 3.1 | 0.4 | 33.9 | |
| Human | Autosomes[ii] | 348,845 | 17.0 | 14.3 | 6.8 | 2.4 | 40.6 |
| X chromosome[ii] | 56,667 | 30.2 | 9.6 | 9.0 | 2.5 | 51.2 | |
| XIC region | 2300 | 38.9 | 8.4 | 8.6 | 1.3 | 57.2 | |
| XIST introns | 18 | 8.2 | 8.9 | 0.5 | 1.0 | 18.6 | |
| Other introns[iii] | 352 | 47.5 | 7.8 | 9.0 | 2.0 | 66.3 | |
| Bovine | XIC region | 233 | 46.5 | 9.3 | 1.3 | 0.8 | 57.9 |
| XIST introns | 17 | 17.8 | 5.8 | 0.6 | 0.0 | 24.2 |
[i] Sequences extracted from GenBank release 124 (June 2001).
[ii] Data from Bailey et al. (2000).
[iii] Introns of protein-coding genes located in Xic region.