Table 1. Number of age-associated genes in 9 human tissues and permutation test.
| Tissues | Sample Size | Aging genea |
Permutationb |
|||
|---|---|---|---|---|---|---|
| Up | Down | Overall | Frequency | Number | ||
| Adipose | 94 | 652 | 482 | 1134 | 0 | 2.16 |
| Artery | 112 | 2258 | 824 | 3082 | 0 | 5.11 |
| Heart | 83 | 374 | 454 | 828 | 0 | 2.43 |
| Lung | 119 | 329 | 547 | 876 | 0 | 2.95 |
| Muscle | 138 | 766 | 121 | 887 | 0 | 1.53 |
| Nerve | 88 | 116 | 67 | 183 | 0 | 1.47 |
| Skin | 96 | 6 | 6 | 12 | 36 | 7.40 |
| Thyroid | 105 | 2 | 1 | 3 | 10 | 0.34 |
| Blood | 156 | 1381 | 1906 | 3287 | 5 | 82.60 |
aNumber of significant genes after adjusting for 3 types of confounding factors: (1) gender, (2) the top three genotype PCs, and (3) among the top 5 gene expression PCs, the PCs not significantly (p-value > 0.05) correlated with age, and removing 20% low expressed genes in the original expression data. Columns “Up”, “Down”, and “Overall” list the number of up-regulated, down-regulated, and overall aging genes, respectively.
bResults of aging genes from 1,000 permutation tests. The column “Frequency” lists the frequencies of identifying equal or more significant genes in 1,000 permuted datasets than those in the original one. The column “Number” lists the average number of aging genes in 1,000 permutation runs.