851 research outputs found

    The crustal nature of the Chukchi Cap and the Lord Howe Rise

    No full text

    Evaluation of the VISAGE Basic Tool for Appearance and Ancestry Prediction Using PowerSeq Chemistry on the MiSeq FGx System

    Get PDF
    The study of DNA to predict externally visible characteristics (EVCs) and the biogeographical ancestry (BGA) from unknown samples is gaining relevance in forensic genetics. Technical developments in Massively Parallel Sequencing (MPS) enable the simultaneous analysis of hundreds of DNA markers, which improves successful Forensic DNA Phenotyping (FDP). The EU-funded VISAGE (VISible Attributes through GEnomics) Consortium has developed various targeted MPS-based lab tools to apply FDP in routine forensic analyses. Here, we present an evaluation of the VISAGE Basic tool for appearance and ancestry prediction based on PowerSeq chemistry (Promega) on a MiSeq FGx System (Illumina). The panel consists of 153 single nucleotide polymorphisms (SNPs) that provide information about EVCs (41 SNPs for eye, hair and skin color from HIrisPlex-S) and continental BGA (115 SNPs; three overlap with the EVCs SNP set). The assay was evaluated for sensitivity, repeatability and genotyping concordance, as well as its performance with casework-type samples. This targeted MPS assay provided complete genotypes at all 153 SNPs down to 125 pg of input DNA and 99.67% correct genotypes at 50 pg. It was robust in terms of repeatability and concordance and provided useful results with casework-type samples. The results suggest that this MPS assay is a useful tool for basic appearance and ancestry prediction in forensic genetics for users interested in applying PowerSeq chemistry and MiSeq for this purpose

    The ancestry of eastern paraguay: A typical south american profile with a unique pattern of admixture

    Get PDF
    Immigrants from diverse origins have arrived in Paraguay and produced important demographic changes in a territory initially inhabited by indigenous Guarani. Few studies have been performed to estimate the proportion of Native ancestry that is still preserved in Paraguay and the role of females and males in admixture processes. Therefore, 548 individuals from eastern Paraguay were genotyped for three marker sets: mtDNA, Y-SNPs and autosomal AIM-InDels. A genetic homogeneity was found between departments for each set of markers, supported by the demographic data collected, which showed that only 43% of the individuals have the same birthplace as their parents. The results show a sex-biased intermarriage, with higher maternal than paternal Native American ancestry. Within the native mtDNA lineages in Paraguay (87.2% of the total), most haplogroups have a broad distribution across the subcontinent, and only few are concentrated around the Paraná River basin. The frequency distribution of the European paternal lineages in Paraguay (92.2% of the total) showed a major contribution from the Iberian region. In addition to the remaining legacy of the colonial period, the joint analysis of the different types of markers included in this study revealed the impact of post-war migrations on the current genetic background of Paraguay.Funding: F.S. and L.G. were supported by Fundação de Amparo à Pesquisa do Rio de Janeiro–FAPERJ, Brazil (process E-26/202.275/2019 and CNE-2018). L.G. was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico–CNPq, Brazil (ref. 306342/2019-7). V.G. is supported by FCT under the program contract provided in Decree-Law no.57/2016 of August 29

    Reflections on Air Capture: the political economy of active intervention in the global environment

    Full text link
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47530/1/10584_2005_Article_9032.pd

    Lack of gene-language correlation due to reciprocal female but directional male admixture in Austronesians and non-Austronesians of East Timor

    Get PDF
    Nusa Tenggara, including East Timor, located at the crossroad between Island Southeast Asia, Near Oceania, and Australia, are characterized by a complex cultural structure harbouring speakers from two different major linguistic groups of different geographic origins (Austronesian (AN) and non-Austronesian (NAN)). This provides suitable possibilities to study gene-language relationship; however, previous studies from other parts of Nusa Tenggara reported conflicting evidence about gene-language correlation in this region. Aiming to investigate gene-language relationships including sex-mediated aspects in East Timor, we analysed the paternally inherited non-recombining part of the Y chromosome (NRY) and the maternally inherited mitochondrial (mt) DNA in a representative collection of AN-and NAN-speaking groups. Y-SNP (single-nucleotide polymorphism) data were newly generated for 273 samples and combined with previously established Y-STR (short tandem repeat) data of the same samples, and with previously established mtDNA data of 290 different samples with, however, very similar representation of geographic and linguistic coverage of the country. We found NRY and mtDNA haplogroups of previously described putative East/Southeast Asian (E/SEA) and Near Oceanian (NO) origins in both AN and NAN speakers of East Timor, albeit in different proportions, suggesting reciprocal genetic admixture between both linguistic groups for females, but directional admixture for males. Our data underline the dual genetic origin of East Timorese in E/SEA and NO, and highlight that substantial genetic admixtur

    The mitogenome portrait of Umbria in Central Italy as depicted by contemporary inhabitants and pre-Roman remains

    Get PDF
    Umbria is located in Central Italy and took the name from its ancient inhabitants, the Umbri, whose origins are still debated. Here, we investigated the mitochondrial DNA (mtDNA) variation of 545 present-day Umbrians (with 198 entire mitogenomes) and 28 pre-Roman individuals (obtaining 19 ancient mtDNAs) excavated from the necropolis of Plestia. We found a rather homogeneous distribution of western Eurasian lineages across the region, with few notable exceptions. Contemporary inhabitants of the eastern part, delimited by the Tiber River and the Apennine Mountains, manifest a peculiar mitochondrial proximity to central-eastern Europeans, mainly due to haplogroups U4 and U5a, and an overrepresentation of J (30%) similar to the pre-Roman remains, also excavated in East Umbria. Local genetic continuities are further attested to by six terminal branches (H1e1, J1c3, J2b1, U2e2a, U8b1b1 and K1a4a) shared between ancient and modern mitogenomes. Eventually, we identified multiple inputs from various population sources that likely shaped the mitochondrial gene pool of ancient Umbri over time, since early Neolithic, including gene flows with central-eastern Europe. This diachronic mtDNA portrait of Umbria fits well with the genome-wide population structure identified on the entire peninsula and with historical sources that list the Umbri among the most ancient Italic populations.We are grateful to Soprintendenza Archeologia, Belle Arti e Paesaggio dell’Umbria, to Istituto Comprensivo Statale Foligno 5 (Perugia) and to all the volunteers who generously participated in this survey and made this research possible. We thank our colleagues Prof. Fausto Panara and Dr. Livia Lucentini with whom we have been discussing the feasibility and the first steps of this project, and Prof. Cristina Cereda, Dr. Gaetano Grieco, Dr. Marialuisa Valente, Dr. Nicole Huber and Jannika Oeke for technical support. We would like to thank the two anonymous reviewers for their suggestions and thoughtful comments. This research received support from: the Italian Ministry of Education, University and Research projects FIR2012 RBFR126B8I (to AO and AA), PRIN2017 20174BTC4R (to AA); Dipartimenti di Eccellenza Program (2018–2022)—Department of Biology and Biotechnology “L. Spallanzani,” University of Pavia (to AA, AO, OS and AT) and Department of Biology, University of Florence (to DC); the Fondazione Cariplo (project no. 2018–2045 to AA, AO and AT); the Fon-dazione Carifol (2008 to AA) and the Tiroler Wissenschaftsfonds (TWF) (UNI-404/1998) (to MB)

    Geometry-controlled kinetics

    Full text link
    It has long been appreciated that transport properties can control reaction kinetics. This effect can be characterized by the time it takes a diffusing molecule to reach a target -- the first-passage time (FPT). Although essential to quantify the kinetics of reactions on all time scales, determining the FPT distribution was deemed so far intractable. Here, we calculate analytically this FPT distribution and show that transport processes as various as regular diffusion, anomalous diffusion, diffusion in disordered media and in fractals fall into the same universality classes. Beyond this theoretical aspect, this result changes the views on standard reaction kinetics. More precisely, we argue that geometry can become a key parameter so far ignored in this context, and introduce the concept of "geometry-controlled kinetics". These findings could help understand the crucial role of spatial organization of genes in transcription kinetics, and more generally the impact of geometry on diffusion-limited reactions.Comment: Submitted versio
    • …
    corecore