Related Experiment Video
Updated: Jun 21, 2025
06:18
Optimized Bone Sampling Protocols for the Retrieval of Ancient DNA from Archaeological Remains
Published on: November 30, 2021
3.8K
Testing times: disentangling admixture histories in recent and complex demographies using ancient DNA
Matthew P Williams1, Pavel Flegontov2,3, Robert Maier3
1Department of Biology, Pennsylvania State University, University Park, PA 16802, USA.
Genetics
|July 16, 2024
Summary
Paleogenomics accurately reconstructs recent human history using admixture inference methods like qpAdm. Population differentiation is key to method performance, even with complex gene flow.
Area of Science:
- Paleogenomics
- Human Evolutionary History
- Population Genetics
Background:
- Paleogenomics has advanced understanding of human evolution, particularly in recent history.
- Assessing the accuracy of paleogenomic methods for historical and archaeological questions is crucial due to increasing demographic complexity and reduced genetic differentiation.
Purpose of the Study:
- To evaluate the performance of qpAdm and f3-statistic admixture inference methods.
- To assess their behavior under diverse demographic models and ancient DNA data conditions.
Main Methods:
- Two simulation approaches were used: exploring demographic parameter space with branch-length data and analyzing Eurasian history with whole-genome data under ancient DNA conditions (SNP ascertainment, missingness, pseudohaploidization).
- Evaluated qpAdm and f3-statistic performance on admixture inference.
Main Results:
- Population differentiation is the primary driver of qpAdm performance.
- Complex gene flow histories do not reduce overall performance but influence model plausibility.
- qpAdm accurately identifies true models among closely related populations under historical conditions.
- A heuristic combining qpAdm P-values and f3-statistics improves fine-scaled hypothesis resolution.
- Whole-genome branch-length f2-statistics significantly enhance qpAdm performance.
Conclusions:
- qpAdm is a reliable method for admixture inference, especially when population differentiation is high.
- The proposed heuristic aids in distinguishing between closely related demographic models.
- Advancements in f-statistic estimations, particularly with whole-genome data, promise improved demographic inference in paleogenomics.
Related Concept Videos
02:54Evolutionary Relationships through Genome Comparisons
5.7K
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
5.7K
03:00Next-generation Sequencing
88.6K
The first human genome sequencing project cost $2.7 billion and was declared complete in 2003, after 15 years of international cooperation and collaboration between several research teams and funding agencies. Today, with the advent of next-generation sequencing technologies, the cost and time of sequencing a human genome have dropped over 100 fold.
Next-Generation Sequencing Methods
Although all next-generation methods use different technologies, they all share a set of standard features....
Next-Generation Sequencing Methods
Although all next-generation methods use different technologies, they all share a set of standard features....
88.6K
02:29Hybrid Zones
17.0K
Hybrid zones are narrow regions where two closely related species interact, mate, and produce hybrids. Relative to either parent species, hybrids may possess distinct phenotypic or genetic differences that impact their survival and reproductive success. The genetic variances introduced by hybridization influence species diversity and speciation processes within the hybrid zone.
17.0K
02:05Gene Evolution - Fast or Slow?
7.1K
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...
7.1K
01:57Sanger Sequencing
754.0K
DNA sequencing is a fundamental technique that is routinely used in the biological sciences. This method can be applied to a range of questions at different scales - from the sequencing of a cloned DNA fragment or the study of a mutation in a gene up to whole-genome sequencing. However, despite the widespread use of sequencing today, it was not until 1977 that Fredrick Sanger and his collaborators developed the chain-termination method to decode DNA sequences. It relies on the separation of a...
754.0K
01:24DNA Isolation
38.7K
DNA isolation protocols can be fast and straightforward or complex and time-consuming depending on the type and quality of DNA required for further processing. For example, plasmid DNA extraction is a bit more complicated than genomic DNA extraction because of the need for an appropriate lysis method to separate plasmid DNA from gDNA during isolation. However, for specific applications, such as long-range DNA sequencing that require a good yield of high- quality DNA samples, we need to follow...
38.7K