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Biology subjects

Feeney, R. N. M.

Publications and source records attributed to Feeney, R. N. M..

2 recordsLinked to original sources

Genome-scale sequencing and analysis of human, wolf and bison DNA from 25,000 year-old sediment

Archaeological sediments have been shown to preserve ancient DNA, but so far have not yielded genome-scale information of the magnitude of skeletal remains. We retrieved and analysed human and mammalian low-coverage nuclear and high-coverage mitochondrial genomes from Upper Palaeolithic sediments from Satsurblia cave, western Georgia, dated to 25,000 years ago. First, a human female genome with substantial basal Eurasian ancestry, which was an ancestry component of the majority of post-Ice Age people in the Near East, North Africa, and parts of Europe. Second, a wolf genome that is basal to extant Eurasian wolves and dogs and represents a previously unknown, likely extinct, Caucasian lineage that diverged from the ancestors of modern wolves and dogs before these diversified. Third, a bison genome that is basal to present-day populations, suggesting that population structure has been substantially reshaped since the Last Glacial Maximum. Our results provide new insights into the late Pleistocene genetic histories of these three species, and demonstrate that sediment DNA can be used not only for species identification, but also be a source of genome-wide ancestry information and genetic history. HighlightsO_LIWe demonstrate for the first time that genome sequencing from sediments is comparable to that of skeletal remains C_LIO_LIA single Pleistocene sediment sample from the Caucasus yielded three low-coverage mammalian ancient genomes C_LIO_LIWe show that sediment ancient DNA can reveal important aspects of the human and faunal past C_LIO_LIEvidence of an uncharacterized human lineage from the Caucasus before the Last Glacial Maximum C_LIO_LI[~]0.01-fold coverage wolf and bison genomes are both basal to present-day diversity, suggesting reshaping of population structure in both species C_LI

developmental biology

An open-sourced bioinformatic pipeline for the processing of Next-Generation Sequencing derived nucleotide reads: Identification and authentication of ancient metagenomic DNA.

Bioinformatic pipelines optimised for the processing and assessment of metagenomic ancient DNA (aDNA) are needed for studies that do not make use of high yielding DNA capture techniques. These bioinformatic pipelines are traditionally optimised for broad aDNA purposes, are contingent on selection biases and are associated with high costs. Here we present a bioinformatic pipeline optimised for the identification and assessment of ancient metagenomic DNA without the use of expensive DNA capture techniques. Our pipeline actively conserves aDNA reads, allowing the application of a bioinformatic approach by identifying the shortest reads possible for analysis (22-28bp). The time required for processing is drastically reduced through the use of a 10% segmented non-redundant sequence file (229 hours to 53). Processing speed is improved through the optimisation of BLAST parameters (53 hours to 48). Additionally, the use of multi-alignment authentication in the identification of taxa increases overall confidence of metagenomic results. DNA yields are further increased through the use of an optimal MAPQ setting (MAPQ 25) and the optimisation of the duplicate removal process using multiple sequence identifiers (a 4.35-6.88% better retention). Moreover, characteristic aDNA damage patterns are used to bioinformatically assess ancient vs. modern DNA origin throughout pipeline development. Of additional value, this pipeline uses open-source technologies, which increases its accessibility to the scientific community.

genomics