Phylogenetic and Geospatial Evidence of Canine Parvovirus Transmission between Wild Dogs and Domestic Dogs at the Urban Fringe in Australia

Canine parvovirus (CPV) is an important cause of disease in domestic dogs. Sporadic cases and outbreaks occur across Australia and worldwide and are associated with high morbidity and mortality. Whether transmission of CPV occurs between owned dogs and populations of wild dogs, including Canis familiaris, Canis lupus dingo and hybrids, is not known. To investigate the role of wild dogs in CPV epidemiology in Australia, PCR was used to detect CPV DNA in tissue from wild dogs culled in the peri-urban regions of two Australian states, between August 2012 and May 2015. CPV DNA was detected in 4.7% (8/170). There was a strong geospatial association between wild-dog CPV infections and domestic-dog CPV cases reported to a national disease surveillance system between 2009 and 2015. Postcodes in which wild dogs tested positive for CPV were 8.63 times more likely to also have domestic-dog cases reported than postcodes in which wild dogs tested negative (p = 0.0332). Phylogenetic analysis of CPV VP2 sequences from wild dogs showed they were all CPV-2a variants characterized by a novel amino acid mutation (21-Ala) recently identified in CPV isolates from owned dogs in Australia with parvoviral enteritis. Wild-dog CPV VP2 sequences were compared to those from owned domestic dogs in Australia. For one domestic-dog case located approximately 10 km from a wild-dog capture location, and reported 3.5 years after the nearest wild dog was sampled, the virus was demonstrated to have a closely related common ancestor. This study provides phylogenetic and geospatial evidence of CPV transmission between wild and domestic dogs in Australia

Domestic Cat Hepadnavirus: Molecular Epidemiology and Phylogeny in Cats in Hong Kong

Domestic cat hepadnavirus (DCH) is an emerging virus related to the hepatitis B virus (HBV). The pathogenic potential of DCH in cats remains to be established. The molecular prevalence of DCH varies widely in the regions investigated so far. The aim of this study was to determine the prevalence, load, and risk factors for DCH detection among cats in Hong Kong, and to generate molecular and epidemiological data on the DCH strains circulating in cats in Hong Kong. DCH DNA was detected using DCH-specific qPCR in 57/513 (11.1%) residual diagnostic blood samples from owned cats. The median viral load was 8.85 × 103 copies/mL of whole blood (range for the 5th to the 95th percentile, 3.33 × 103 to 2.2 × 105 copies per mL). Two outliers had higher viral loads of 1.88 × 107 copies/mL and 4.90 × 109 copies/mL. DCH was detected in cats from 3 months to 19 years of age. Sex, age, neuter status, breed, or elevated serum alanine aminotransferase were not statistically associated with DCH DNA detection. On phylogenetic analysis based on 12 complete genome sequences, the Hong Kong DCH viruses clustered in Genotype A with viruses from Australia and Asia (clade A1), distinct from viruses from Europe (clade A2). Sequence analysis found that DCH has similar epsilon and direct repeat regions to human HBV, suggesting a conserved method of replication. Based on our findings, the DCH strains circulating in Hong Kong are a continuum of the Asiatic strains

Bitter taste receptor polymorphisms and human aging.

Several studies have shown that genetic factors account for 25% of the variation in human life span. On the basis of published molecular, genetic and epidemiological data, we hypothesized that genetic polymorphisms of taste receptors, which modulate food preferences but are also expressed in a number of organs and regulate food absorption processing and metabolism, could modulate the aging process. Using a tagging approach, we investigated the possible associations between longevity and the common genetic variation at the three bitter taste receptor gene clusters on chromosomes 5, 7 and 12 in a population of 941 individuals ranging in age from 20 to 106 years from the South of Italy. We found that one polymorphism, rs978739, situated 212 bp upstream of the TAS2R16 gene, shows a statistically significant association (p = 0.001) with longevity. In particular, the frequency of A/A homozygotes increases gradually from 35% in subjects aged 20 to 70 up to 55% in centenarians. These data provide suggestive evidence on the possible correlation between human longevity and taste genetics

Global diversity in the TAS2R38 bitter taste receptor: Revisiting a classic evolutionary PROPosal

The ability to taste phenylthiocarbamide (PTC) and 6-n-propylthiouracil (PROP) is a polymorphic trait mediated by the TAS2R38 bitter taste receptor gene. It has long been hypothesized that global genetic diversity at this locus evolved under pervasive pressures from balancing natural selection. However, recent high-resolution population genetic studies of TAS2Rs suggest that demographic events have played a critical role in the evolution of these genes. We here utilized the largest TAS2R38 database yet analyzed, consisting of 5,589 individuals from 105 populations, to examine natural selection, haplotype frequencies and linkage disequilibrium to estimate the effects of both selection and demography on contemporary patterns of variation at this locus. We found signs of an ancient balancing selection acting on this gene but no post Out-Of-Africa departures from neutrality, implying that the current observed patterns of variation can be predominantly explained by demographic, rather than selective events. In addition, we found signatures of ancient selective forces acting on different African TAS2R38 haplotypes. Collectively our results provide evidence for a relaxation of recent selective forces acting on this gene and a revised hypothesis for the origins of the present-day worldwide distribution of TAS2R38 haplotypes

Association between TAS2R38 gene polymorphisms and colorectal cancer risk

Molecular sensing in the lingual mucosa and in the gastro-intestinal tract play a role in the detection of ingested harmful drugs and toxins. Therefore, genetic polymorphisms affecting the capability of initiating these responses may be critical for the subsequent efficiency of avoiding and/or eliminating possible threats to the organism. By using a tagging approach in the region of Taste Receptor 2R38 (TAS2R38) gene, we investigated all the common genetic variation of this gene region in relation to colorectal cancer risk with a case-control study in a German population (709 controls and 602 cases) and in a Czech population (623 controls and 601 cases). We found that there were no significant associations between individual SNPs of the TAS2R38 gene and colorectal cancer in the Czech or in the German population, nor in the joint analysis. However, when we analyzed the diplotypes and the phenotypes we found that the non-taster group had an increased risk of colorectal cancer in comparison to the taster group. This association was borderline significant in the Czech population, (OR = 1.28, 95% CI 0.99-1.67; P(value) = 0.058) and statistically significant in the German population (OR = 1.36, 95% CI 1.06-1.75; P(value) = 0.016) and in the joint analysis (OR = 1.34, 95% CI 1.12-1.61; P(value) = 0.001). In conclusion, we found a suggestive association between the human bitter tasting phenotype and the risk of CRC in two different populations of Caucasian origin

Hepadnavirus DNA Is Detected in Canine Blood Samples in Hong Kong but Not in Liver Biopsies of Chronic Hepatitis or Hepatocellular Carcinoma

Chronic hepatitis and hepatocellular carcinoma (HCC) caused by the hepadnavirus hepatitis B virus (HBV) are significant causes of human mortality. A hepatitis-B-like virus infecting cats, domestic cat hepadnavirus (DCH), was reported in 2018. DCH DNA is hepatotropic and detectable in feline blood or serum (3.2 to 12.3%). Detection of HBV DNA has been reported in sera from 10% of free-roaming dogs in Brazil, whereas 6.3% of sera from dogs in Italy tested positive for DCH DNA by real-time quantitative PCR (qPCR). If DCH, HBV, or another hepadnavirus is hepatotropic in dogs, a role for such a virus in the etiology of canine idiopathic chronic hepatitis (CH) or HCC warrants investigation. This study investigated whether DCH DNA could be detected via qPCR in blood from dogs in Hong Kong and also whether liver biopsies from dogs with confirmed idiopathic CH or HCC contained hepadnaviral DNA using two panhepadnavirus conventional PCRs (cPCR) and a DCH-specific cPCR. DCH DNA was amplified from 2 of 501 (0.4%) canine whole-blood DNA samples. A second sample taken 6 or 7 months later from each dog tested negative in DCH qPCR. DNA extracted from 101 liver biopsies from dogs in Hong Kong or the USA, diagnosed by board-certified pathologists as idiopathic CH (n = 47) or HCC (n = 54), tested negative for DCH DNA and also tested negative using panhepadnavirus cPCRs. This study confirms that DCH DNA can be detected in canine blood by qPCR, although at a much lower prevalence than that reported previously. We identified no evidence to support a pathogenic role for a hepadnavirus in canine idiopathic CH or HCC

Faecal virome of the Australian grey-headed flying fox from urban/ suburban environments contains novel coronaviruses, retroviruses and sapoviruses

Bats are important reservoirs for viruses of public health and veterinary concern. Virus studies in Australian bats usually target the families Paramyxoviridae, Coronaviridae and Rhabdoviridae, with little known about their overall virome composition. We used metatranscriptomic sequencing to characterise the faecal virome of greyheaded flying foxes from three colonies in urban/suburban locations from two Australian states. We identified viruses from three mammalian-infecting (Coronaviridae, Caliciviridae, Retroviridae) and one possible mammalianinfecting (Birnaviridae) family. Of particular interest were a novel bat betacoronavirus (subgenus Nobecovirus) and a novel bat sapovirus (Caliciviridae), the first identified in Australian bats, as well as a potentially exogenous retrovirus. The novel betacoronavirus was detected in two sampling locations 1375 km apart and falls in a viral lineage likely with a long association with bats. This study highlights the utility of unbiased sequencing of faecal samples for identifying novel viruses and revealing broad-scale patterns of virus ecology and evolution

Association Between TAS2R38 Gene Polymorphisms and Colorectal Cancer Risk: A Case-Control Study in Two Independent Populations of Caucasian Origin

Molecular sensing in the lingual mucosa and in the gastro-intestinal tract play a role in the detection of ingested harmful drugs and toxins. Therefore, genetic polymorphisms affecting the capability of initiating these responses may be critical for the subsequent efficiency of avoiding and/or eliminating possible threats to the organism. By using a tagging approach in the region of Taste Receptor 2R38 (TAS2R38) gene, we investigated all the common genetic variation of this gene region in relation to colorectal cancer risk with a case-control study in a German population (709 controls and 602 cases) and in a Czech population (623 controls and 601 cases). We found that there were no significant associations between individual SNPs of the TAS2R38 gene and colorectal cancer in the Czech or in the German population, nor in the joint analysis. However, when we analyzed the diplotypes and the phenotypes we found that the non-taster group had an increased risk of colorectal cancer in comparison to the taster group. This association was borderline significant in the Czech population, (OR = 1.28, 95% CI 0.99–1.67; Pvalue = 0.058) and statistically significant in the German population (OR = 1.36, 95% CI 1.06–1.75; Pvalue = 0.016) and in the joint analysis (OR = 1.34, 95% CI 1.12–1.61; Pvalue = 0.001). In conclusion, we found a suggestive association between the human bitter tasting phenotype and the risk of CRC in two different populations of Caucasian origin

Mappatura genetica di una mutazione recessiva spontenea murina associata a fenotipo neurologico riconducibile ad epilessia

I modelli di topo rappresentano un valido sistema di studio per l’identificazione dei geni nonché per la comprensione dei meccanismi molecolari alla base dell’insorgenza di malattie ereditarie umane. Le epilessie sono malattie caratterizzate da ricorrenza cronica di crisi epilettiche, dovute a scariche elettriche anomale e sincronizzate della corteccia o del tronco cerebrale. Nell’uomo l’epilessia è considerata una malattia geneticamente eterogenea, risulta pertanto molto utile avere a disposizione un numero molteplice di mutanti di topo da utilizzare come modelli sperimentali. Lo studio di questi modelli può fornire informazioni essenziali sulle anomalie molecolari e fisiologiche associate ad epilessia, e consentire quindi di capire quali siano le dinamiche genetiche molecolari responsabili dello sviluppo di questa complessa patologia. Il topo énervé (nrv) viene proposto come modello murino di epilessia causato da mutazione spontanea recessiva, osservata in un topo a fondo genetico ibrido C57BL6/MBT allevato dal Prof. Guenet presso l’Istituto Pasteur di Parigi. Ad oggi sono state condotte solo alcune analisi preliminari per la caratterizzazione del fenotipo (brevi video riprese dell’animale, analisi preliminari di foot-print, analisi istologiche). I risultati di tali analisi indicano chiaramente la presenza di un fenotipo neurologico. In particolare emergono in maniera evidente una camminata anomala caratterizzata da tremore e momenti di crisi con caratteristiche simili alle crisi epilettiche umane. L’analisi istologica del cervello non ha mostrato alcuna anomalia evidente. Per identificare la mutazione a livello molecolare è stato intrapreso, in collaborazione con il Prof. Guenet, un approccio di clonaggio posizionale. Presso l’Istituto Pasteur è stato allestito un inincrocio tra animali eterozigoti obbligati per la mutazione énervé (+/nrv) con lo scopo di ottenere una generazione (F2) di topi da utilizzare per la localizzazione del difetto molecolare. Allo scopo di mappare la mutazione, il DNA estratto da code di animali F2 affetti è stato utilizzato per l’analisi dei marcatori microsatelliti del DNA attraverso PCR (reazione a catena della polimerasi) e successiva analisi elettroforetica su gel di agarosio. Tale lavoro è stato svolto in parte presso il laboratorio di Genetica dell’Università di Pisa ed in parte presso l’Istituto Pasteur di Parigi. L’associazione del fenotipo epilettico negli animali omozigoti con uno specifico aplotipo di determinati marcatori cromosomici, permette di localizzare, in loro corrispondenza la mutazione in esame. I risultati ottenuti hanno permesso di mappare la mutazione nrv sul cromosoma 4 in un intervallo di circa 5.5 cM. Allo scopo di ridurre ulteriormente l’intervallo cromosomico in questione le analisi per la mappatura della mutazione nrv sono tuttora in corso

TAS2RS BITTER TASTE GENES AND HUMAN VARIABILITY IN BEHAVIOR, DISEASE SUSCEPTIBILITY AND LONGEVITY

Initially, this work is focused on role of the polymorphic bitter taste gene, TAS2R38, involved in the perception of the bitter synthetic chemical phenylthiocarbamide (PTC), in food preference life style, as alcohol and smoke intake. We have considered a sample 1706 university students (17-25 years old) from different part of Italy: Palermo, Catania Cosenza and Caltanissetta University (South Italy); Pisa, Lucca, Terni and Roma University (Centre Italy); Parma and Brescia University( North Italy). They have been enrolled in the study. PTC “Taster” and “Non Taster” subjects were discriminated by means of tasting soaked papers in PTC different solutions. DNA was extracted from saliva, and genotyped by TaqMan assay for of TAS2R38 SNPs (Single Nucleotide Polymorphism) A possible association between genotype and food preference was assessed by administering a detailed questionnaire. Our Results shown: 1) the entire population was found to be in Hardy –Weimberg equilibrium. 2) No significant difference in allele frequencies between Centre and South Italy was observed, while significant differences between genotype distribution and European population as Germany, Czchoslovakia and Italy. 3) A good correlation (80%) between TA2R38 polymorphism and capability to assess PTC bitterness was observed. 4) A non statistically significant correlation between smoke intake and genotype, instead significant correlation between alcohol intake and genotype,(p=0.03).5) we have no found statistically significant indication that TA2R38 polymorphism (genotype) is associated with the preference of some food. Since previous reports showed a modest association between greater sensitivity to PROP and a higher number of colonic polyps, suggesting that PROP status could provide a link between vegetable intake and colon cancer risk, we have considered a study of cases-control, from Germany and Czech Republic. Cases are positive colonoscopic results for malignancy, histologically confirmed as colon or rectal carcinomas. we found no statistically significant association between TAS2R38 SNPs and colorectal cancer risk, considering major TAS2R38 genotypes: Chi-squared=4.65 and p=0.097 and rare genotype, Chi-squared=0.73 and p=0.95.Molecular sensing of luminal contents also initiates hormonal and/or neural pathways leading to the regulation of caloric intake, pancreatic insulin secretion, and metabolism TAS2R14 has been shown to be activated by various substances, several of which are powerful toxic agents like picrotoxin and aristolochic acid which is a strong carcinogen. In the same case-control study, we have explored also the role of three tagging polymorphisms in the TAS2R14 gene, in conclusion we can confidently exclude a major role for common polymorphisms of the TAS2R14 gene in colorectal cancer risk in this population. Other published report shown that bitter taste receptors are also expressed in subsets of cells within the mammalian gastrointestinal tract, where they mediate nutrient assimilation and endocrine responses, suggesting that a functionally compromised TAS2R receptor negatively impacts glucose homeostasis, providing an important link between alimentary chemosensation and metabolic disease. We started to investigate the possible influence of TAS2Rs genes on longevity, considering a elderly elderly (60-104) population of South Italy, and we have found a statistically significant association between TAS2R16 polymorphism: rs978739 and aging; (p<0.001), a statistically significant association between other TAS2R16 polymorphism: rs6466849 with blood level of cholesterol (p=0.01), further we have found a statistically significant association between TAS2R46 polymorphism: rs2708380 and BMI; Chi-squared=17.23 and p=0.0085. There reasons are unclear so, our goal is confirmed and clarify if TAS2R16 SNPs are same effect rispectively on age and blood level cholesterol, well as TAS2R46 polymorphism: rs2708380 influence BMI level