Temin H M
McArdle Laboratory for Cancer Research, University of Wisconsin, Madison 53706.
Mol Biol Evol. 1985 Nov;2(6):455-68. doi: 10.1093/oxfordjournals.molbev.a040365.
Recent studies indicate that greater than 10% of the human and mouse genome appears to consist of integrated DNA copies of RNA molecules. These sequences include retroviruses, retrovirus-like DNAs, retrotransposons, and retrotranscripts and represent more than 500,000 separate integration events. The nature of the enzymes used for the reverse transcription from RNA to DNA and for integration of the DNA copies into chromosomal DNA is unknown. A major evolutionary effect of these integrations would have been mutation. Thus, present-day organisms are those that survived this mutational load.
近期研究表明，人类和小鼠基因组中超过10%的部分似乎由RNA分子的整合DNA拷贝组成。这些序列包括逆转录病毒、类逆转录病毒DNA、逆转座子和逆转录转录本，代表了超过50万个独立的整合事件。用于从RNA逆转录为DNA以及将DNA拷贝整合到染色体DNA中的酶的性质尚不清楚。这些整合的一个主要进化效应可能是突变。因此，当今的生物是那些在这种突变负荷中存活下来的生物。
