Castri Loredana, Luiselli Donata, Pettener Davide, Melendez-Obando Mauricio, Villegas-Palma Ramón, Barrantes Ramiro, Madrigal Lorena
1 Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Università di Bologna, Bologna, Italy.
Hum Biol. 2014 Fall;86(4):251-9. doi: 10.13110/humanbiology.86.4.0251.
Interest in mitochondrial influences on extended longevity has been mounting, as evidenced by a growing literature. Such work has demonstrated that some haplogroups are associated with increased longevity and that such associations are population specific. Most previous work, however, suffers from the methodological shortcoming that long-lived individuals are compared with "controls" who are born decades after the aged individuals. The only true controls of the elderly are people who were born in the same time period but who did not have extended longevity. Here we present results of a study in which we are able to test whether longevity is independent of haplogroup type, controlling for time period, by using mtDNA genealogies. Since mtDNA does not recombine, we know the mtDNA haplogroup of the maternal ancestors of our living participants. Thus, we can compare the haplogroup of people with and without extended longevity who were born during the same time period. Our sample is an admixed New World population that has haplogroups of Amerindian, European, and African origin. We show that women who belong to Amerindian, European, and African haplogroups do not differ in their mean longevity. Therefore, to the extent that ethnicity was tied in this population to mtDNA make-up, such ethnicity did not impact longevity. In support of previous suggestions that the link between mtDNA haplogroups and longevity is specific to the population being studied, we found an association between haplogroup C and decreased longevity. Interestingly, the lifetime reproductive success and the number of grandchildren produced via a daughter of women with haplogroup C are not reduced. Our diachronic approach to the mtDNA and longevity link allowed us to determine that the same haplogroup is associated with decreased longevity during different time periods and allowed us to compare the haplogroup of short- and long-lived individuals born during the same time period. By controlling for time period, we minimized the effect of different cultural and ecological environments on differential longevity. With our diachronic approach, we investigated the mtDNA and longevity link with a biocultural perspective.
线粒体对延长寿命的影响引发的关注日益增加，越来越多的文献证明了这一点。此类研究表明，某些单倍群与寿命延长相关，且这种关联具有人群特异性。然而，此前的大多数研究存在方法上的缺陷，即长寿个体与比老年个体晚出生数十年的“对照组”进行比较。老年人唯一真正的对照组是出生在同一时期但未长寿的人。在此，我们展示一项研究的结果，在该研究中，我们能够通过使用线粒体DNA谱系来检验寿命是否独立于单倍群类型，并控制时间段因素。由于线粒体DNA不会重组，我们知道在世参与者的母系祖先的线粒体DNA单倍群。因此，我们可以比较同一时期出生的有和没有延长寿命的人的单倍群。我们的样本是一个混合的新大陆人群，具有美洲印第安人、欧洲人和非洲人起源的单倍群。我们发现，属于美洲印第安人、欧洲人和非洲人单倍群的女性在平均寿命上没有差异。因此，就该人群中种族与线粒体DNA构成相关而言，这种种族并未影响寿命。为支持之前关于线粒体DNA单倍群与寿命之间的联系特定于所研究人群的观点，我们发现单倍群C与寿命缩短有关。有趣的是，单倍群C的女性通过女儿产生的终身繁殖成功率和孙辈数量并未减少。我们对线粒体DNA与寿命联系的历时性研究方法使我们能够确定，同一单倍群在不同时间段与寿命缩短相关，并使我们能够比较同一时期出生的短寿和长寿个体的单倍群。通过控制时间段，我们将不同文化和生态环境对寿命差异的影响降至最低。通过我们的历时性研究方法，我们从生物文化的角度研究了线粒体DNA与寿命的联系。
