一些物种适应能力非常强，一些物种到了陌生环境则很难生存。日本东北大学研究人员发现，这可能与它们体内重复基因的个数有关：重复基因越多的物种，生存和适应能力就越强，分布范围也更广。

东北大学研究生院生命科学研究科的新闻公报说，一个基因拷贝形成两个基因称作基因的重复，重复形成的基因则称作重复基因。比如，人类基因组的70％以上是重复基因。

生命科学研究科教授河田雅圭领导的研究小组就基因重复与生物适应环境能力的关系进行研究。他们曾在2012年通过实验发现，果蝇的生存环境越是多样，其拥有的重复基因就越多。此次，研究小组又利用基因组已获得破译的猴子、老鼠和兔子等16种哺乳动物进行研究，调查了这些动物生存的气候带、食性等环境的多样性与重复基因比例的关系，并得出了相同的结论。

研究小组认为，哺乳动物重复基因的数量与适应环境能力的关系与果蝇一致，而且这一规则很可能适用于任何生物。

他们认为，基因重复产生两个功能完全相同的重复基因，即使其中一个基因的功能丧失或降低也不会给生命活动带来太大障碍。

这项研究的意义在于，或许能推测物种能在多大程度上适应气候变化等环境的剧烈变化，从而判断物种是否会成为适应环境能力很强的外来入侵物种。这一研究成果首次在基因级别弄清了生物获得适应多种环境能力的机制，有可能成为制订保护生物战略的新指标。相关论文已刊登在新一期英国科学杂志《分子生物学与进化》网络版上。（来源：新华社 蓝建中）

Contribution of non-ohnologous duplicated genes to high habitat variability

 in mammals

Abstract  The mechanism by which genetic systems affect environmental adaptation is a focus of considerable attention in the fields of ecology, evolution, and conservation. However, the genomic characteristics that constrain adaptive evolution have remained unknown. A recent study showed that the proportion of duplicated genes in whole Drosophila genomes correlated with environmental variability within habitat, but it remains unclear whether the correlation is observed even in vertebrates whose genomes including a large number of duplicated genes generated by whole genome duplication (WGD). Here we focus on fully sequenced mammalian genomes that experienced WGD in early vertebrate lineages and show that the proportion of small-scale duplication (SSD) genes in the genome, but not that of WGD genes, is significantly correlated with habitat variability. Moreover, species with low habitat variability have a higher proportion of lost duplicated genes, particularly SSD genes, than those with high habitat variability. These results indicate that species that inhabit variable environments may maintain more SSD genes in their genomes, and suggest that SSD genes are important for adapting to novel environments and surviving environmental changes. These insights may be applied to predicting invasive and endangered species.

原文链接：http://mbe.oxfordjournals.org/content/early/2014/04/26/molbev.msu128.full.pdf+html