据研究人员报告，那些活到110岁甚至更久的人其实也和普通人一样有很多与疾病相关的基因，但是，所不同的是，他们同时又兼具与之相对应的保护基因。所以，他们才得以如此长寿。
一个由美国科学家组成的团队发现所谓的百岁老人实际上是非常罕见的——在发达国家，5,000,000个人中才会出现一个。越来越多的证据显示，基因在这其中发挥了非常重要的作用。
在这项被他们称作“史无前例”的研究中，研究者们分别对两位114岁高龄的老爷爷和老奶奶进行了全基因组分析，结果发现他们拥有和普通人一样多的疾病相关基因。
比方说，这位老爷爷拥有37种能增加结肠癌风险的突变基因。
“事实上，早年他也曾患过梗阻性结肠癌，所幸的是，后来癌细胞并没有扩散并且已经通过手术成功治愈了。即便在临死之前，他的身体状况和认知能力也表现得相当惊人。” 英国百岁老人研究主任Thomas Perls博士在波士顿大学医学中心新闻发布会上说。
而这位老奶奶则拥有众多与“老年病”有关的突变基因，比如心脏病、癌症以阿尔茨海默氏病。她之前就被确诊为充血性心力衰竭和轻度认知功能障碍，但是直到她108岁时这些病症才开始慢慢显现。
“百岁老人拥有和其他人一样多的疾病相关突变基因，这是我们以及其他研究者都公认的事实。也许，这其中的区别在于百岁老人们同时还拥有长寿相关的突变型，可以抵消疾病相关基因，这样就使得疾病不会发生——或者就算发生了，在这群几乎达到人类寿命极限的人身上，也不会表现出那么强的致病性。” Perls说。
这项研究发表在1月3日出版的《Frontiers in Genetics》杂志上。
Whole genome sequences of a male and female supercentenarian, ages greater than 114 years
Paola Sebastiani, Alberto Riva, Monty Montano, Phillip Pham, Ali Torkamani, Eugene Scherba, Gary Benson, Jacqueline N. Milton, Clinton T. Baldwin, Stacy Andersen, Nicholas J. Schork, Martin H. Steinberg and Thomas T. Perls
Supercentenarians (age 110+ years old) generally delay or escape age-related diseases and disability well beyond the age of 100 and this exceptional survival is likely to be influenced by a genetic predisposition that includes both common and rare genetic variants. In this report, we describe the complete genomic sequences of male and female supercentenarians, both age >114 years old. We show that: (1) the sequence variant spectrum of these two individuals’ DNA sequences is largely comparable to existing non-supercentenarian genomes; (2) the two individuals do not appear to carry most of the well-established human longevity enabling variants already reported in the literature; (3) they have a comparable number of known disease-associated variants relative to most human genomes sequenced to-date; (4) approximately 1% of the variants these individuals possess are novel and may point to new genes involved in exceptional longevity; and (5) both individuals are enriched for coding variants near longevity-associated variants that we discovered through a large genome-wide association study. These analyses suggest that there are both common and rare longevity-associated variants that may counter the effects of disease-predisposing variants and extend lifespan. The continued analysis of the genomes of these and other rare individuals who have survived to extremely old ages should provide insight into the processes that contribute to the maintenance of health during extreme aging.
文献链接：https://www.frontiersin.org/genetics_of_aging/10.3389/fgene.2011.00090/abstract
