Abstract：
Epigenetic approaches for estimating the age of living organisms are revolutionizing studies of long-lived species. Molecular biomarkers that allow age estimates from small tissue biopsies promise to enhance studies of long-lived whales, addressing a fundamental and challenging parameter in wildlife management. DNA methylation (DNAm) can affect gene expression, and strong correlations between DNAm patterns and age have been documented in humans and nonhuman vertebrates and used to construct \"epigenetic clocks\". We present several epigenetic clocks for skin samples from two of the longest-lived cetaceans, killer whales and bowhead whales. Applying the mammalian methylation array to genomic DNA from skin samples we validate four different clocks with median errors of 2.3-3.7 years. These epigenetic clocks demonstrate the validity of using cytosine methylation data to estimate the age of long-lived cetaceans and have broad applications supporting the conservation and management of long-lived cetaceans using genomic DNA from remote tissue biopsies.
摘要：
估算生物体年龄的表观遗传方法正在彻底改变对长寿物种的研究。允许从小组织活检中估计年龄的分子生物标志物有望加强对长寿鲸鱼的研究，解决野生动物管理中的一个基本和具有挑战性的参数。DNA甲基化（DNAm）可以影响基因表达，DNAm模式和年龄之间的强相关性已在人类和非人类脊椎动物中得到证明，并用于构建“表观遗传钟”。我们介绍了两种寿命最长的鲸类动物的皮肤样本的几个表观遗传时钟，虎鲸和弓头鲸.将哺乳动物甲基化阵列应用于皮肤样品的基因组DNA，我们验证了四个不同的时钟，中位误差为2.3-3.7年。这些表观遗传时钟证明了使用胞嘧啶甲基化数据来估计长寿鲸目动物的年龄的有效性，并且具有广泛的应用，支持使用来自远程组织活检的基因组DNA来保护和管理长寿鲸目动物。
