In 2010, researchers published the first genome sequence from an ancient human, using tufts of hair from a man who lived around 4,000 years ago in Greenland ¹ . In the 13 years since, scientists have generated genome data from more than 10,000 ancient people — and there’s no sign of a slowdown.

“I feel truly gobsmacked that we have gotten to this point,” says David Reich, a population geneticist at Harvard Medical School in Boston, Massachusetts. His team maintains a database of published ancient-human genome data, called the Allen Ancient DNA Resource, which was described this month in a preprint study on bioRxiv ² .

Before 2010, ancient-DNA studies focused on limited stretches of DNA, such as the roughly 16,500-base-pair-long mitochondrial genome or short segments of the nearly 3.1 billion base pairs in the human genome. Since then, advances in DNA sequencing have made it feasible to decode entire ancient genomes. Initially, this process was labour-intensive, and relied on finding rare samples with high levels of genuine ancient DNA. As a result, it took several years to generate genome data from a dozen individuals.

Each year since 2018, researchers have produced genome data from thousands of ancient humans, thanks to technological advances in DNA sequencing and extraction methods. For many samples — including those from Reich’s lab — researchers sequence a set of one million DNA bases that tend to vary between people, instead of an entire genome, which is much costlier.

The field’s exponential growth has also been propelled by a focus on more recent samples from the 12,000 years since the last ice age ended, which are more abundant and tend to have higher-quality DNA than older human remains.

Global genomics

The vast majority of ancient-human genomes come from people who lived in Western Eurasia, an area encompassing Europe, Russia and the Middle East. Since 2012, most genomes have come from Europe and Russia, although there has been a modest decline in that proportion since 2015.

Sampling from other regions, particularly East Asia, Oceania and Africa, is becoming more frequent. Africa’s centrality to the human story means that it is especially important for its proportion to grow, says Reich, who was part of a team that published the largest-yet ancient-genome study from Africa last month ³ .

Divided by DNA: The uneasy relationship between archaeology and ancient genomics

Ancient-human genomes might be growing in number and global diversity, but this is being driven by a small number of labs, says María Ávila-Arcos, a palaeogenomicist at the National Autonomous University of Mexico in Mexico City. “They hop region to region to address these big questions and sequence as many genomes as they can.”

As ancient genomics becomes increasingly global, Ávila-Arcos would like researchers to generate smaller numbers of genomes — sparing precious samples — to address questions important to communities and scientists in the regions where they originate. “We need to shift that focus and obsession with numbers,” she says.

Nearly 80% of ancient-human genome sequences in the database come from just three institutions, according to Reich, whose own group contributed nearly half of the total (others are based at the University of Copenhagen and two Max Planck Institutes in Germany). Building the capacity to do ancient genomics in under-represented parts of the world is “extremely important”, says Reich, who is attending a conference in Kenya next month called DNAirobi , with this goal in mind.

article_text: In 2010, researchers published the first genome sequence from an ancient human, using tufts of hair from a man who lived around 4,000 years ago in Greenland1. In the 13 years since, scientists have generated genome data from more than 10,000 ancient people — and there’s no sign of a slowdown. “I feel truly gobsmacked that we have gotten to this point,” says David Reich, a population geneticist at Harvard Medical School in Boston, Massachusetts. His team maintains a database of published ancient-human genome data, called the Allen Ancient DNA Resource, which was described this month in a preprint study on bioRxiv2. Before 2010, ancient-DNA studies focused on limited stretches of DNA, such as the roughly 16,500-base-pair-long mitochondrial genome or short segments of the nearly 3.1 billion base pairs in the human genome. Since then, advances in DNA sequencing have made it feasible to decode entire ancient genomes. Initially, this process was labour-intensive, and relied on finding rare samples with high levels of genuine ancient DNA. As a result, it took several years to generate genome data from a dozen individuals. Each year since 2018, researchers have produced genome data from thousands of ancient humans, thanks to technological advances in DNA sequencing and extraction methods. For many samples — including those from Reich’s lab — researchers sequence a set of one million DNA bases that tend to vary between people, instead of an entire genome, which is much costlier. The field’s exponential growth has also been propelled by a focus on more recent samples from the 12,000 years since the last ice age ended, which are more abundant and tend to have higher-quality DNA than older human remains. The vast majority of ancient-human genomes come from people who lived in Western Eurasia, an area encompassing Europe, Russia and the Middle East. Since 2012, most genomes have come from Europe and Russia, although there has been a modest decline in that proportion since 2015. Sampling from other regions, particularly East Asia, Oceania and Africa, is becoming more frequent. Africa’s centrality to the human story means that it is especially important for its proportion to grow, says Reich, who was part of a team that published the largest-yet ancient-genome study from Africa last month3.

Divided by DNA: The uneasy relationship between archaeology and ancient genomics

Ancient-human genomes might be growing in number and global diversity, but this is being driven by a small number of labs, says María Ávila-Arcos, a palaeogenomicist at the National Autonomous University of Mexico in Mexico City. “They hop region to region to address these big questions and sequence as many genomes as they can.” As ancient genomics becomes increasingly global, Ávila-Arcos would like researchers to generate smaller numbers of genomes — sparing precious samples — to address questions important to communities and scientists in the regions where they originate. “We need to shift that focus and obsession with numbers,” she says. Nearly 80% of ancient-human genome sequences in the database come from just three institutions, according to Reich, whose own group contributed nearly half of the total (others are based at the University of Copenhagen and two Max Planck Institutes in Germany). Building the capacity to do ancient genomics in under-represented parts of the world is “extremely important”, says Reich, who is attending a conference in Kenya next month called DNAirobi, with this goal in mind. vocabulary:

{'Gobsmacked': '惊讶的，大吃一惊的', 'BioRxiv': '生物学预印本，一个开放访问的学术期刊，用于发布生物学领域的预印本文章', 'Mitochondrial': '线粒体的，线粒体是细胞中的一种小型细胞器，负责细胞能量的生成', 'Palaeogenomicist': '古代基因组学家，研究古代生物的基因组学', 'Autonomous': '自治的，独立的', 'Encompassing': '包含的，囊括的', 'Proportion': '比例，部分', 'Modest': '适度的，有节制的', 'Abundant': '丰富的，充裕的', 'Feasible': '可行的，可实现的', 'Labour-intensive': '劳动密集型的，需要大量劳动的', 'Genuine': '真实的，真正的', 'Exponential': '指数的，指数级的', 'Propel': '推动，驱动', 'Vast': '巨大的，庞大的', 'Eurasia': '欧亚大陆，欧亚大陆是欧洲和亚洲的结合体', 'Encompass': '包含，囊括', 'Obsession': '痴迷，强迫症', 'Centrality': '中心性，中心地位', 'Capacity': '能力，容量', 'Sparing': '节省，缓解', 'Attending': '参加，出席'} readguide:

{'reading_guide': '2010年，研究人员发表了第一个古代人类基因组序列，使用来自格陵兰岛约4000年前生活的男性的头发束。在此之后的13年中，科学家们已经从10000多个古代人身上生成了基因组数据，而且还没有减缓的迹象。这篇文章将讨论古代人类基因组研究的发展，以及如何改变研究重点，以更好地反映世界各地的社区和科学家的关注。'} long_sentences:

{'sentence 1': '技術上，這個過程最初是一個費力的過程，並且依賴於尋找罕見的樣本，其中含有高水平的真正古代DNA。因此，它需要幾年時間才能從十幾個個體中生成基因組數據。', 'sentence 2': '由於DNA測序和提取方法的技術進步，從2018年開始，研究人員每年都能從數千古代人類中生成基因組數據。'}

sentence 1: 技術上，這個過程最初是一個費力的過程，並且依賴於尋找罕見的樣本，其中含有高水平的真正古代DNA。因此，它需要幾年時間才能從十幾個個體中生成基因組數據。

句子結構：主詞為“它”，謂語為“需要幾年時間”，修飾語為“技術上，這個過程最初是一個費力的過程，並且依賴於尋找罕見的樣本，其中含有高水平的真正古代DNA”，句子為陳述句。

語義：句子表達的是，由於技術上的限制，從十幾個個體中生成基因組數據需要花費許多時間。

sentence 2: 由於DNA測序和提取方法的技術進步，從2018年開始，研究人員每年都能從數千古代人類中生成基因組數據。

句子結構：主詞為“研究人員”，謂語為“能從數千古代人類中生成基因組數據”，修飾語為“由於DNA測序和提取方法的技術進步，從2018年開始”，句子為陳述句。

語義：句子表達的是，由於DNA測序和提取方法的技術進步，從2018年開始，研究人員每年都能從數千古代人類中生成基因組數據。