Search results for "genetic variation"

Long live the alien: is high genetic diversity a pivotal aspect of crested porcupine (Hystrix cristata) long-lasting and successful invasion?

2016

AbstractStudying the evolutionary dynamics of an alien species surviving and continuing to expand after several generations can provide fundamental information on the relevant features of clearly successful invasions. Here, we tackle this task by investigating the dynamics of the genetic diversity in invasive crested porcupine (Hystrix cristata) populations, introduced to Italy about 1500 years ago, which are still growing in size, distribution range and ecological niche. Using genome-wide RAD markers, we describe the structure of the genetic diversity and the demographic dynamics of theH. cristatainvasive populations and compare their genetic diversity with that of native African populatio…

2017

Abstract Background Results on the association between prenatal exposure to methylmercury (MeHg) and child neuropsychological development are heterogeneous. Underlying genetic differences across study populations could contribute to this varied response to MeHg. Studies in Drosophila have identified the cytochrome p 450 3A (CYP3A) family as candidate MeHg susceptibility genes. Objectives We evaluated whether genetic variation in CYP3A genes influences the association between prenatal exposure to MeHg and child neuropsychological development. Methods The study population included 2639 children from three birth cohort studies: two subcohorts in Seychelles (SCDS) (n = 1160, 20 and 30 months of…

Effect of gene-gene and gene-environment interactions associated with antituberculosis drug-induced hepatotoxicity.

2017

This study evaluated the association between environmental factors and genetic variations in enzymes that metabolize antituberculosis (anti-TB) drugs [arylamine N-acetyltransferase 2, cytochrome P450 2E1 (CYP2E1), glutathione S-transferase theta 1 (GSTT1), and glutathione S-transferase mu 1] with antituberculosis drug-induced hepatotoxicity (ATDH). We also investigated the potential gene-gene and gene-environment interactions as well as their association with ATDH development in a population of hospitalized TB patients from Buenos Aires.We investigated 364 TB patients who received anti-TB drugs. Physicians collected demographic and clinical data to identify environmental risk factors for AT…

Phylogenetic analysis of an epidemic outbreak of acute hepatitis C in HIV-infected patients by ultra-deep pyrosequencing.

2017

Abstract Background The incidence of acute hepatitis C (AHC) among HIV-infected men who have sex with men (MSM) has increased significantly in the last 10 years. Several studies point to a social and sexual network of HIV-positive MSM that extends internationally. Objectives The aim of our study was to investigate the dynamics of HCV transmission in an outbreak of AHC in HIV-infected MSM in Barcelona by ultra-deep pyrosequencing. Study design Between 2008 and 2013, 113 cases of AHC in HIV-infected MSM were diagnosed in the Infectious Diseases Unit, Hospital Clinic, Barcelona. Massive sequencing was performed using the Roche 454 GS Junior platform. To define possible transmission networks, m…

Simultaneous infection of cattle with different Anaplasma phagocytophilum variants.

2019

Anaplasma phagocytophilum is a tick-transmitted Gram-negative obligate intracellular bacterium that replicates in neutrophil granulocytes. It causes tick-borne fever in cattle and sheep. We report here the case of a 5-year-old cow from Germany with clinically overt granulocytic anaplasmosis presenting with fever, lower limb oedema and drop in milk-yield. The herd encompassed 10 animals, 8 other animals showed subclinical infection. The strains from the 9 A. phagocytophilum positive cows were molecularly characterized using ankA gene-based and multilocus sequence typing (MLST). Seven of 9 (78%) animals were infected simultaneously with different ankA variants belonging to ankA clusters I and…

Diversity, evolution, and function of myriapod hemocyanins.

2018

Background Hemocyanin transports O2 in the hemolymph of many arthropod species. Such respiratory proteins have long been considered unnecessary in Myriapoda. As a result, the presence of hemocyanin in Myriapoda has long been overlooked. We analyzed transcriptome and genome sequences from all major myriapod taxa – Chilopoda, Diplopoda, Symphyla, and Pauropoda – with the aim of identifying hemocyanin-like proteins. Results We investigated the genomes and transcriptomes of 56 myriapod species and identified 46 novel full-length hemocyanin subunit sequences in 20 species of Chilopoda, Diplopoda, and Symphyla, but not Pauropoda. We found in Cleidogona sp. (Diplopoda, Chordeumatida) a hemocyanin-…

2017

The consequences of emerging marine diseases on the evolutionary trajectories of affected host populations in the marine realm are largely unexplored. Evolution in response to natural selection depends on the genetic variation of the traits under selection and the interaction of these traits with the environment (GxE). However, in the case of diseases, genotypes of pathogens add another dimension to this interaction. Therefore, the study of disease resistance needs to be extended to the interaction of host genotype, pathogen genotype and environment (GxGxE). In the present study we used a full-sib breeding design crossing two genetically differentiated populations of the Pacific oyster Cras…

2018

The retrieval of ancient DNA from osteological material provides direct evidence of human genetic diversity in the past. Ancient DNA samples are often used to investigate whether there was population continuity in the settlement history of an area. Methods based on the serial coalescent algorithm have been developed to test whether the population continuity hypothesis can be statistically rejected by analysing DNA samples from the same region but of different ages. Rejection of this hypothesis is indicative of a large genetic shift, possibly due to immigration occurring between two sampling times. However, this approach is only able to reject a model of full continuity model (a total absenc…

Targeting the Heterogeneity of Cancer with Individualized Neoepitope Vaccines

2015

Abstract Somatic mutations binding to the patient's MHC and recognized by autologous T cells (neoepitopes) are ideal cancer vaccine targets. They combine a favorable safety profile due to a lack of expression in healthy tissues with a high likelihood of immunogenicity, as T cells recognizing neoepitopes are not shaped by central immune tolerance. Proteins mutated in cancer (neoantigens) shared by patients have been explored as vaccine targets for many years. Shared (“public”) mutations, however, are rare, as the vast majority of cancer mutations in a given tumor are unique for the individual patient. Recently, the novel concept of truly individualized cancer vaccination emerged, which explo…

The Barrett‐associated variants at GDF 7 and TBX 5 also increase esophageal adenocarcinoma risk

2016

Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) represent two stages within the esophagitis-metaplasia-dysplasia-adenocarcinoma sequence. Previously genetic risk factors have been identified that confer risk to BE and EAC development. However, to which extent the genetic variants confer risk to different stages of the BE/EAC sequence remains mainly unknown. In this study we analyzed three most recently identified BE variants at the genes GDF7 (rs3072), TBX5 (rs2701108), and ALDH1A2 (rs3784262) separately in BE and EAC samples in order to determine their risk effects during BE/EAC sequence. Our data show that rs3072 at GDF7 and rs2701108 at TBX5 are also associated with EAC and …