Biémont Christian, Vieira Cristina
UMR CNRS 5558: Biométrie et Biologie Evolutive, Université Lyon 1, 69622 Villeurbanne.
J Soc Biol. 2004;198(4):413-7.
Genome size displays an important variability between species without any direct link to complexity. This paradox, so-called "C value paradox", now becomes understood as resulting from a differential abundance of numerous repeated sequences, among which transposable elements. Genomes indeed contain a important proportion of such sequences (95 % of DNA in man, about 45 % of which are transposable elements, up to 99 % of DNA in some plants). While most investigations until now are focalized on genes or coding sequences, which thus represent a small part of the genome, more attention now is dedicated on so-called non-coding sequences. Transposable elements, which are capable of moving around in genomes, inducing mutations, chromosomal rearrangements, gene expression regulations, thus appear as major actors in diversity and evolution. We present here a brief review of the most prominent acquisition in this expanding domain.
基因组大小在不同物种间表现出重要的变异性，且与复杂性没有直接联系。这种矛盾，即所谓的“C值悖论”，现在被理解为是由众多重复序列（其中包括转座元件）的丰度差异导致的。基因组中确实包含很大比例的此类序列（人类DNA的95%，其中约45%是转座元件，在某些植物中高达DNA的99%）。虽然迄今为止大多数研究都集中在基因或编码序列上，而这些仅占基因组的一小部分，但现在更多的注意力被投向了所谓的非编码序列。转座元件能够在基因组中移动，引发突变、染色体重排、基因表达调控，因此在多样性和进化中似乎是主要参与者。我们在此简要回顾一下这个不断扩展的领域中最显著的成果。
