Project description:BackgroundMarker gene surveys have a wide variety of applications in species identification, population genetics, and molecular epidemiology. As these methods expand to new types of organisms and additional markers beyond 16S and 18S rRNA genes, comprehensive databases are a critical requirement for proper analysis of these data.ResultsHere we present an ITS2 rDNA database for marker gene surveys of both free-living and parasitic nematode populations and the software used to build the database. This is currently the most complete and up-to-date ITS2 database for nematodes and is able to reproduce previous analysis that used a smaller database.ConclusionsThis database is an important resource for researchers working on nematodes and also provides a tool to create ITS2 databases for any given taxonomy.
Project description:The Kashmiri population is an ethno-linguistic group that resides in the Kashmir Valley in northern India. A longstanding hypothesis is that this population derives ancestry from Jewish and/or Greek sources. There is historical and archaeological evidence of ancient Greek presence in India and Kashmir. Further, some historical accounts suggest ancient Hebrew ancestry as well. To date, it has not been determined whether signatures of Greek or Jewish admixture can be detected in the Kashmiri population. Using genome-wide genotyping and admixture detection methods, we determined there are no significant or substantial signs of Greek or Jewish admixture in modern-day Kashmiris. The ancestry of Kashmiri Tibetans was also determined, which showed signs of admixture with populations from northern India and west Eurasia. These results contribute to our understanding of the existing population structure in northern India and its surrounding geographical areas.
Project description:Spotted hyena (Crocuta crocuta) is the only extant species of the genus Crocuta, which once occupied a much wider range during the Pliocene and Pleistocene. However, its origin and evolutionary history is somewhat contentious due to discordances being found between morphological, nuclear, and mitochondrial data. Due to the limited molecular data from east Asian Crocuta, and the difficulty of extracting ancient DNA from this area, here we present proteomic analysis of cave hyenas from three locations in northern China. This marks the first proteomic data generated from cave hyenas, adding new molecular data to the east Asian populations. Phylogenetic analysis based on these protein sequences reveals two different groups of cave hyenas in east Asia, one of which could not be distinguished from modern spotted hyenas from northern Africa, tentatively the result of previously suggested gene flow between these lineages. With developments of instrumentation and analytical methods, proteomics holds promising potential for the phylogenetic reconstruction of ancient fauna previously thought to be unreachable using ancient DNA.
Project description:BackgroundDNA barcoding can be used to authenticate Ganoderma species for safe use. This study aims to identify commercial products containing Ganoderma using DNA barcoding.MethodsWe used 63 internal transcribed spacer (ITS) 2 sequences of Ganoderma species from 33 newly-sequenced wild samples, crude drugs, mycelia, spores, and authentic extracts and spore oils collected from various locations and markets, as well as 30 sequences from GenBank. Sequences were assembled and aligned using CodonCode Aligner V3.71. Intra- and inter-specific distances were estimated by MEGA 6.0, and phylogeny reconstruction was based on the K2P model. SNP(s) and RNA secondary structure of ITS2 were analyzed and compared among closely related Ganoderma species.ResultsG. lucidum cultivated in China was different from those cultivated in Europe. "Chizhi" (G. lucidum) and "Zizhi" (G. sinense) were clustered into two clades that were separated from the other Ganoderma species. The fruiting bodies and commercial products of G. lucidum and G. sinense were successfully distinguished from those of other Ganoderma species by comparing the ITS2 sequences and RNA secondary structures.ConclusionThe DNA barcoding method is applicable to the authentication of commercial products containing Ganoderma species.