Table 1.
General sequence properties of human genes
| imprinted | maternally expressed | paternally expressed | autosomal | |
|---|---|---|---|---|
| G+C content of genes | 46.56% | 46.91% | 45.98% | 45.47% |
| CpGobs/CpGexp of genes | 0.305 | 0.305 | 0.315 | 0.280 |
| gene length (bp) | 29641 | 46976 | 26829 | 22422 |
| intron length (bp) | 1637* | 1652 | 1633 | 1549 |
| length of intergenic regions (bp) | 50879* | 49483 | 55322 | 26410 |
| coverage of introns with purely intronic PCSs | 0.74% | 0.69% | 1.09% | 0.45% |
| purely intronic PCSs per 10 kb of intron per gene | 1.72 | 1.35 | 2.04 | 1.06 |
| coverage of intergenic regions with PCSs | 0.66% | 0.74% | 0.64% | 1.11% |
| intergenic PCSs per 10 kb per gene | 1.29 | 1.41 | 1.29 | 2.17 |
* p < 0.01 (Wilcoxon test for comparison with autosomal genes)
Gene length: length of transcribed DNA sequence from most upstream transcriptional start site to most downstream transcriptional termination site; intergenic region: For this, the intergenic segments between any two genes were cut into two halves. Each of them was assigned to the closest gene. As intergenic region of a gene we then added the lengths of the halved upstream intergenic segment and of the halved downstream intergenic segment. Since the features show a highly skewed distribution, medians are given instead of averages and standard deviations.