Recombination in Eukaryotic Single Stranded DNA Viruses

Although single stranded (ss) DNA viruses that infect humans and their domesticated animals do not generally cause major diseases, the arthropod borne ssDNA viruses of plants do, and as a result seriously constrain food production in most temperate regions of the world. Besides the well known plant and animal-infecting ssDNA viruses, it has recently become apparent through metagenomic surveys of ssDNA molecules that there also exist large numbers of other diverse ssDNA viruses within almost all terrestrial and aquatic environments. The host ranges of these viruses probably span the tree of life and they are likely to be important components of global ecosystems. Various lines of evidence suggest that a pivotal evolutionary process during the generation of this global ssDNA virus diversity has probably been genetic recombination. High rates of homologous recombination, non-homologous recombination and genome component reassortment are known to occur within and between various different ssDNA virus species and we look here at the various roles that these different types of recombination may play, both in the day-to-day biology, and in the longer term evolution, of these viruses. We specifically focus on the ecological, biochemical and selective factors underlying patterns of genetic exchange detectable amongst the ssDNA viruses and discuss how these should all be considered when assessing the adaptive value of recombination during ssDNA virus evolution

D’os et d’ADN : interactions et complémentarités méthodologiques pour l’étude des infections chroniques dans les populations du passé

Depuis plusieurs décennies, paléopathologie et paléomicrobiologie œuvrent de concert afin d’éclairer notre connaissance des phénomènes infectieux chroniques dans les populations anciennes. Du point de vue moléculaire, les méthodologies aujourd’hui employées sont très variables, de même que les intentions qui président à leurs utilisations : confirmations diagnostiques, caractérisations des agents pathogènes et de leurs histoires évolutives, ou encore paléo- épidémiologie des séries ostéoarché..

Parvovirus 4 in French in-patients: a study of haemodialysis and lung transplant cohorts

International audienceThe epidemiology and the clinical implication of human parvovirus 4 (PARV4) in human populations is still under evaluation. The distribution of PARV4 DNA was determined in cohorts of French haemodialysis and lung transplant patients. Plasma samples (n=289) were tested for PARV4 by real-time PCR assay (ORF2), and amplification products selected at random were sequenced. Analysis of available serological and biological markers was also undertaken. Fifty-seven samples out of 185 (30.8%) were positive for PARV4 DNA in the cohort of haemodialysis patients. A higher prevalence of the virus was identified in individuals with markers of HBV infection. PARV4 was also identified in 14 out of 104 samples (13.5%) from lung transplant recipients, with no clear-cut association with available clinical markers. Point mutations located on the zone of real-time detection were identified for some amplification products. This study describes the detection of PARV4 in the blood of haemodialysis and lung transplanted patients with significant difference in prevalence in these two cohorts. Further studies will be needed in order to understand better both the potential implication in host health and the natural history of this virus

Variola virus in a 300-year-old Siberian mummy.

International audienceNo abstract available

Clinical Profile of Cardiac Involvement in Danon Disease: A Multicenter European Registry.

Background: The X-linked Danon disease manifests by severe cardiomyopathy, myopathy, and neuropsychiatric problems. We designed this registry to generate a comprehensive picture of clinical presentations and outcome of patients with Danon disease in cardiomyopathy centers throughout Europe. Methods: Clinical and genetic data were collected in 16 cardiology centers from 8 European countries. Results: The cohort comprised 30 male and 27 female patients. The age at diagnosis was birth to 42 years in men and 2 to 65 in women. Cardiac involvement was observed in 96%. Extracardiac manifestations were prominent in men but not in women. Left ventricular (LV) hypertrophy was reported in 73% of male and 74% of female patients. LV systolic dysfunction was reported in 40% of men (who had LV ejection fraction, 34±11%) and 59% of women (LV ejection fraction, 28±13%). The risk of arrhythmia and heart failure was comparable among sexes. The age of first heart failure hospitalization was lower in men (18±6 versus 28±17 years; P<0.003). Heart failure was the leading cause of death (10 of 17; 59%), and LV systolic dysfunction predicted an adverse outcome. Eight men and 8 women (28%) underwent heart transplantation or received an LV assist device. Our cohort suggests better prognosis of female compared with male heart transplant recipients. Conclusions: Danon disease presents earlier in men than in women and runs a malignant course in both sexes, due to cardiac complications. Cardiomyopathy features, heart failure and arrhythmia, are similar among the sexes. Clinical diagnosis and management is extremely challenging in women due to phenotypic diversity and the absence of extracardiac manifestations.pre-print507 K

Emery-Dreifuss muscular dystrophy Type 1 is associated with a high risk of malignant ventricular arrhythmias and end-stage heart failure

BACKGROUND AND AIMS: Emery-Dreifuss muscular dystrophy (EDMD) is caused by variants in EMD (EDMD1) and LMNA (EDMD2). Cardiac conduction defects and atrial arrhythmia are common to both, but LMNA variants also cause end-stage heart failure (ESHF) and malignant ventricular arrhythmia (MVA). This study aimed to better characterise the cardiac complications of EMD variants. METHODS: Consecutively referred EMD variant-carriers were retrospectively recruited from 12 international cardiomyopathy units. MVA and ESHF incidence in male and female variant-carriers was determined. Male EMD variant-carriers with a cardiac phenotype at baseline (EMDCARDIAC) were compared to consecutively recruited male LMNA variant-carriers with a cardiac phenotype at baseline (LMNACARDIAC). RESULTS: Longitudinal follow-up data were available for 38 male and 21 female EMD variant-carriers (mean [SD] ages 33.4 [13.3] and 43.3 [16.8] years, respectively). Nine (23.6%) males developed MVA and five (13.2%) developed ESHF during a median [IQR] follow-up of 65.0 [24.3, 109.5] months. No female EMD variant-carrier had MVA or ESHF, but nine (42.8%) developed a cardiac phenotype at a median [IQR] age of 58.6 [53.2, 60.4] years. Incidence rates for MVA were similar for EMDCARDIAC and LMNACARDIAC (4.8 and 6.6 per 100 person-years, respectively; log-rank p = 0.49). Incidence rates for ESHF were 2.4 and 5.9 per 100 person-years for EMDCARDIAC and LMNACARDIAC, respectively (log-rank p = 0.09). CONCLUSIONS: Male EMD variant-carriers have a risk of progressive heart failure and ventricular arrhythmias similar to that of male LMNA variant-carriers. Early implantable cardioverter defibrillator implantation and heart failure drug therapy should be considered in male EMD variant-carriers with cardiac disease

Emery-Dreifuss Muscular Dystrophy 1 is associated with high risk of malignant ventricular arrhythmias and end-stage heart failure.

BACKGROUND AND AIMS Emery-Dreifuss muscular dystrophy (EDMD) is caused by variants in EMD (EDMD1) and LMNA (EDMD2). Cardiac conduction defects and atrial arrhythmia are common to both, but LMNA variants also cause end-stage heart failure (ESHF) and malignant ventricular arrhythmia (MVA). This study aimed to better characterise the cardiac complications of EMD variants. METHODS Consecutively referred EMD variant-carriers were retrospectively recruited from 12 international cardiomyopathy units. MVA and ESHF incidence in male and female variant-carriers was determined. Male EMD variant-carriers with a cardiac phenotype at baseline (EMDCARDIAC) were compared to consecutively recruited male LMNA variant-carriers with a cardiac phenotype at baseline (LMNACARDIAC). RESULTS Longitudinal follow-up data were available for 38 male and 21 female EMD variant-carriers (mean [SD] ages 33.4 [13.3] and 43.3 [16.8] years, respectively). Nine (23.6%) males developed MVA and five (13.2%) developed ESHF during a median [IQR] follow-up of 65.0 [24.3, 109.5] months. No female EMD variant-carrier had MVA or ESHF, but nine (42.8%) developed a cardiac phenotype at a median [IQR] age of 58.6 [53.2, 60.4] years. Incidence rates for MVA were similar for EMDCARDIAC and LMNACARDIAC (4.8 and 6.6 per 100 person-years, respectively; log-rank p = 0.49). Incidence rates for ESHF were 2.4 and 5.9 per 100 person-years for EMDCARDIAC and LMNACARDIAC, respectively (log-rank p = 0.09). CONCLUSIONS Male EMD variant-carriers have a risk of progressive heart failure and ventricular arrhythmias similar to that of male LMNA variant-carriers. Early implantable cardioverter defibrillator implantation and heart failure drug therapy should be considered in male EMD variant-carriers with cardiac disease.The work reported in this publication was funded by: a British Heart Foundation Clinical Research Training Fellowship to D.E.C. (FS/CRTF/ 20/24022); a British Heart Foundation Clinical Research Training fellowship to A.P. (FS/18/82/34024); The Ministry of Health, Italy, project RC-2022-2773270 to E.B.; the National Institutes of Health (NIH) (R01HL69071, R01HL116906, R01HL147064, NIH/NCATS UL1 TR002535, and UL1 TR001082) to L.M.; and support from the Rose Foundation for K.M.S