In humans, telomeres limit cells to ~50 divisions, which is probably related to how DNA replication is only 99.9998% accurate. After that many divisions, the genome is 0.001% different from when it started, which is one error per 10,000 base pairs, or an error in 1/3 of all genes. This is in addition to the slow rate of spontaneous mutations you accumulate over your lifetime.
Where did you get your numbers? Human DNA replication (in normal cells with no damage) is 99.99999999% accurate (i.e. about 1 mutation per 10^-10 base pairs). Please do not mod parent informative for this misinformative post!
2.4 statute miles of surgical tubing at Yale U. = 1 I.V.League