来源：《新科学家》
原文刊登日期：2022年10月3日
本文适合2024考生
The 2022 Nobel prize in physiology or medicine has been awarded to Svante Pääbo for his discoveries concerning human evolution and the genomes of our extinct human relatives.
2022年诺贝尔生理学或医学奖授予斯万特·帕博，表彰他在人类进化和已灭绝人类亲缘物种基因组方面的发现。
In 1990, Pääbo pioneered methods to sequence ancient DNA by attempting to sequence that of Neanderthal mitochondria, the energy powerhouses of cells. He achieved this using a bone from a Neanderthal that lived 40,000 years ago. DNA degrades and can become contaminated, meaning that sequencing ancient DNA was thought to be impossible.
1990年，帕博通过尝试对尼安德特人线粒体(细胞的能量来源)进行测序，开创了对古代DNA进行测序的方法。他用一块生活在4万年前的尼安德特人的骨头做到了这一点。DNA会降解并被污染，这意味着测序古代DNA曾一度被认为是不可能的。
“Humanity has always been intrigued by its origins,” said Anna Wedell, chair of the Nobel Committee for Physiology or Medicine, at the prize’s announcement on 3 October. “Where do we come from? And how are we related to those who came before us? What makes us different from hominids that went extinct?”
诺贝尔生理学或医学委员会主席安娜·韦德尔在10月3日宣布获奖人时说：“人类总是对自身的起源感兴趣。我们从哪里来？我们与我们之前的人类有什么关系？是什么使我们与灭绝的原始人类不同？”
“Pääbo finally achieved the what was thought to be impossible sequencing and assembly of the Neanderthal genome… and discovered a completely new hominin entirely the Denisovans by analysing and comparing genome sequences,” she said.
她说：“帕博最终实现了尼安德特人基因组的测序和组装，并通过分析和比较基因组序列，发现了一种完全属于丹尼索瓦人的全新古人类。”
Mitochondrial DNA carries very limited information on an individual’s overall physiology, so next Pääbo sequenced ancient DNA packaged in the nucleus of ancient cells. Using three Neanderthal bone specimens from Vindija cave in Croatia, along with others from Germany, Russia and Spain, Pääbo sequenced the 3 billion base pairs of the Neanderthal genome.
线粒体DNA携带的关于个体整体生理学的信息非常有限，因此下一步帕博对包装在细胞核中的古代DNA进行测序。利用来自克罗地亚文迪亚洞穴的三个尼安德特人骨骼标本，以及来自德国、俄罗斯和西班牙的其他标本，帕博对尼安德特族基因组的30亿碱基对进行了测序。
By comparing the Neanderthal genome with that of Homo sapiens, Pääbo revealed that these hominin groups diverged roughly 400,000 to 800,000 years ago and would have bred with each other in western Eurasia after H. sapiens migrated out of Africa around 70,000 years ago. As a result, up to 2 per cent of the genome in people of European or Asian descent originates from Neanderthals, including genes that affect our immune response to infections.
通过比较尼安德特人和智人的基因组，帕博发现，这两种原始人类群体大约在40万至80万年前分化，大约在7万年前智人走出非洲后，会在欧亚大陆西部相互交配繁衍。因此，欧洲人或亚洲人后裔中多达2%的基因组来自尼安德特人，包括影响我们对感染的免疫反应的基因。
In 2008, Pääbo sequenced DNA from a 40,000-year-old finger bone discovered in a cave in southern Siberia. By comparing this DNA with that of both Neanderthals and H. sapiens, he discovered an entirely new type of hominin, the Denisovans.
2008年，帕博对西伯利亚南部一个洞穴中发现的4万年前的指骨进行了DNA测序。通过将这种DNA与尼安德特人和智人的DNA进行比较，他发现了一种全新的古人类——丹尼索瓦人。
Further analysis revealed that H. sapiens bred with Denisovans in eastern parts of Eurasia. As a result, people in Melanesia and parts of south-east Asia have up to 6 per cent Denisovan DNA. Pääbo’s work also supported the discovery that one gene inherited from Denisovans helps present-day Tibetans survive at high altitudes with low oxygen concentrations.
进一步分析发现，智人与欧亚大陆东部的丹尼索瓦人交配过。因此，美拉尼西亚和东南亚部分地区的人有高达6%的丹尼索瓦人DNA。帕博的工作也支持了这一发现：从丹尼索瓦人那里继承来的一种基因帮助今天的西藏人在高海拔和低氧浓度的环境下生存。