Molecular Medicine Research Group, Hungarian Academy of Sciences, Budapest, Hungary.
PLoS One. 2013 Jul 30;8(7):e69805. doi: 10.1371/journal.pone.0069805. Print 2013.
Our bloodstream is considered to be an environment well separated from the outside world and the digestive tract. According to the standard paradigm large macromolecules consumed with food cannot pass directly to the circulatory system. During digestion proteins and DNA are thought to be degraded into small constituents, amino acids and nucleic acids, respectively, and then absorbed by a complex active process and distributed to various parts of the body through the circulation system. Here, based on the analysis of over 1000 human samples from four independent studies, we report evidence that meal-derived DNA fragments which are large enough to carry complete genes can avoid degradation and through an unknown mechanism enter the human circulation system. In one of the blood samples the relative concentration of plant DNA is higher than the human DNA. The plant DNA concentration shows a surprisingly precise log-normal distribution in the plasma samples while non-plasma (cord blood) control sample was found to be free of plant DNA.
我们的血液被认为是与外界和消化道完全隔离的环境。根据标准模式，随食物摄入的大分子物质不能直接进入循环系统。在消化过程中，人们认为蛋白质和 DNA 分别被降解成小分子成分，即氨基酸和核酸，然后通过复杂的主动过程被吸收，并通过循环系统分布到身体的各个部位。在这里，我们基于来自四项独立研究的 1000 多个人类样本的分析，报告了证据表明，足以携带完整基因的膳食衍生 DNA 片段可以避免降解，并通过未知机制进入人体循环系统。在其中一个血液样本中，植物 DNA 的相对浓度高于人体 DNA。在血浆样本中，植物 DNA 的浓度呈现出惊人的精确对数正态分布，而非血浆（脐带血）对照样本则不含植物 DNA。
