Northern European Populations Research Articles

Distribution of Solid Lung Nodules Presence and Size by Age and Sex in a Northern European Nonsmoking Population.

Background Most of the data regarding prevalence and size distribution of solid lung nodules originates from lung cancer screening studies that target high-risk populations or from Asian general cohorts. In recent years, the identification of lung nodules in non-high-risk populations, scanned for clinical indications, has increased. However, little is known about the presence of solid lung nodules in the Northern European nonsmoking population. Purpose To study the prevalence and size distribution of solid lung nodules by age and sex in a nonsmoking population. Materials and Methods Participants included nonsmokers (never or former smokers) from the population-based Imaging in Lifelines study conducted in the Northern Netherlands. Participants (age ≥ 45 years) with completed lung function tests underwent chest low-dose CT scans. Seven trained readers registered the presence and size of solid lung nodules measuring 30 mm3 or greater using semiautomated software. The prevalence and size of lung nodules (≥30 mm3), clinically relevant lung nodules (≥100 mm3), and actionable nodules (≥300 mm3) are presented by 5-year categories and by sex. Results A total of 10 431 participants (median age, 60.4 years [IQR, 53.8-70.8 years]; 56.6% [n = 5908] female participants; 46.1% [n = 4812] never smokers and 53.9% [n = 5619] former smokers) were included. Of these, 42.0% (n = 4377) had at least one lung nodule (male participants, 47.5% [2149 of 4523]; female participants, 37.7% [2228 of 5908]). The prevalence of lung nodules increased from age 45-49.9 years (male participants, 39.4% [219 of 556]; female participants, 27.7% [236 of 851]) to age 80 years or older (male participants, 60.7% [246 of 405]; female participants, 50.9% [163 of 320]). Clinically relevant lung nodules were present in 11.1% (1155 of 10 431) of participants, with prevalence increasing with age (male participants, 8.5%-24.4%; female participants, 3.7%-15.6%), whereas actionable nodules were present in 1.1%-6.4% of male participants and 0.6%-4.9% of female participants. Conclusion Lung nodules were present in a substantial proportion of all age groups in the Northern European nonsmoking population, with slightly higher prevalence for male participants than female participants. © RSNA, 2024 Supplemental material is available for this article.

Integrating Genetics in Glaucoma Screening.

As additional glaucoma genes are identified and classified, polygenic risk scores will be refined, facilitating early diagnosis and treatment. Ensuring genetic research is equitable to prevent glaucoma blindness worldwide is crucial. To review the progress in glaucoma genetics over the past 25 years, including the identification of genes with varying contributions to the disease and the development of polygenic risk scores. Over the last 2 and a half decades, glaucoma genetics has evolved from identifying genes with Mendelian inheritance patterns, such as myocilin and CYP1B1, to the discovery of hundreds of genes associated with the disease. Polygenic risk scores have been developed, primarily based on research in Northern European populations, and efforts to refine these scores are ongoing. However, there is a question regarding their applicability to other ethnic groups, especially those at higher risk of primary open angle glaucoma, like individuals of African ancestry. Glaucoma is highly heritable and family history can be used for cascade clinical screening programs, but these will not be feasible in all populations. Thus, cascade genetic testing using well-established genes such as myocilin may help improve glaucoma diagnosis. In addition, ongoing investigations seek to identify pathogenic genetic variants within genes like myocilin. The expanding availability of genetic testing for various diseases and early access to genetic risk information necessitates further research to determine when and how to act on specific genetic results. Polygenic risk scores involving multiple genes with subtle effects will require continuous refinement to improve clinical utility. This is crucial for effectively interpreting an individual's risk of developing glaucoma and preventing blindness.

Ethical aspects in the prevention of insulin-dependent diabetes mellitus

Insulin-dependent diabetes mellitus (IDDM) seems to be on the rise today, especially in northern European populations. IDDM is a disease that leads to numerous complications (e.g., metabolic decompensation, macroangiopathy, microangiopathy, retinopathy, nephropathy etc.) and requires the individual to be on daily insulin administration, for life.

Converging forms: an examination of sub-Arctic, circumarctic, and Central Asian Ranunculus auricomus agg. populations.

Phenotypic complexity in species complexes and recently radiated lineages has resulted in a diversity of forms that have historically been classified into separate taxa. Increasingly, with the proliferation of high-throughput sequencing methods, additional layers of complexity have been recognized, such as frequent hybridization and reticulation, which may call into question the previous morphological groupings of closely related organisms. We investigated Northern European, Asian, and Beringian populations of Ranunculus auricomus agg. with phylogenomic analysis of 736 genes and 27,586 SNPs in order to deduce the interrelatedness and hybrid origin of this phenotypically and taxonomically complicated group from Europe characterized by a history of hybridization, polyploidy, apomixis, and recent radiation. The ploidy levels and the reproductive mode of the Northern European populations were assessed via flow cytometric seed screening. In addition, in order to examine the phenotypic plasticity of the dwarf forms previously described as species and summarized as the Ranunculus monophyllus group, we conductedclimate chamber experiments under cold (northern) and warm (temperate) conditions. The Northern European populations are tetra- to hexaploid and propagate primarily through apomixis. The complex is characterized by highly reticulate relationships. Genetic differentiation of the main clusters has occurred between the above-mentioned geographical regions. We find evidence for the hybrid origin of the taxa in these areas with differing genomic contributions from the geographically nearest European sexual progenitor species. Furthermore, polyphyly in the taxa of the R. monophyllus group is supported. Experiments show low lability in the traits associated with the R. monophyllus group. We conclude that multiple adaptations of hybrids to colder climates and shorter vegetation periods have shaped the phenotypes of the R. monophyllus group, and we suggest a formal classification as nothotaxa within the R. auricomus group.

Images of Fish in the Rock Art of the Ancient Population of Northern Europe

The article presents the results of the analysis of the study of the image of fish in the rock art of ancient hunters and fishermen of Northern Europe (final VI – III BC). During the study, 134 fish figures were studied on 6 rock paintings and in 17 clusters of petroglyphs of Fennoscandia. The small proportion of fish figures in relation to the total number of images on the rocks of the region, with a high proportion of fishing in the primitive economy, established by bone remains at Neo-Eneolithic sites, suggests a mythological basis for the images under consideration. Spatial differences in the appearance of fish figures in Northern Europe make it possible to distinguish two areas (western and eastern), radically different in the style of the ichthyomorph image. The rock art mainly reflects representatives of the largest fish species that lived in the region: catfish, sturgeon, halibut, pike, salmon, whitefish. In the bone remains at the sites located near the clusters of rock carvings, other types of fish are usually dominant: zander, cod. In the compositions of fishing, as in other hunting scenes carved on the petroglyphs of Fennoscandia, only active methods of its extraction are presented, although there is numerous archaeological evidence of the use by the inhabitants of the region for catching fish and other animals of various types of traps.

Simulating a hybridization event of a range-expanding sexual cannibal (Argiope bruennichi)

Abstract Hybridization plays an important role in animal speciation. Mediterranean populations of the Palaearctic wasp spider Argiope bruennichi have recently undergone a range expansion northwards. Adaptation to colder winters was facilitated by introgressed alleles derived from Asian populations, hence the resulting hybrids were able to expand geographically. Argiope bruennichi exhibits a highly complex mating system that includes strong sexual conflict and predisposes the species to behaviours that could facilitate directed hybridization and hybrid stabilization. To test this, we simulated a hybridization event with European and Asian spiders and a backcrossing event with southern and northern European spiders by conducting mate choice experiments and mating trials. We found pronounced differences in the cannibalism and monopolization successes between the populations. Asian male spiders were more successful in monopolizing European females than their European conspecifics and more successful than European males with Asian females. This would have led to an increased proportion of these specific offspring in the hybrid population. Our results suggest the mating system as a driving factor in the directional hybridization of Asian males and European females and the establishment of new northern European populations of A. bruennichi. We found no influences of the mating system on the stabilization of the resulting hybrid populations, probably owing to cold survival adaptations being a more important factor.

Giant cell arteritis: insights from a monocentric retrospective cohort study.

Giant cell arteritis (GCA), more common in Northern European populations, has limited data in Arabcountries. Our study reports GCA's clinical manifestations in Jordan and reviews published research on GCA across Arab nations. In this retrospective analysis, GCA patients diagnosed from January 2007 to March 2019 at a Jordanian academic medical center were included through referrals for temporal artery biopsy (TAB). A comprehensive search in PubMed, Scopus, and the DOAJ (Directory of Open Access Journals) databases was conducted to identify all relevant English-language manuscripts from Arab countries on GCA without time limitations. Among 59 diagnosed GCA patients, 41 (69.5%) were clinically diagnosed with a negative TAB, and 19 (30.5%) had a positive result. Females comprised 74.6% (n = 44) with 1:3 male-female ratio. The mean age at diagnosis was 67.3 (± 9.5) years, with most presenting within two weeks (n = 40, 67.8%). Headache was reported by 54 patients (91.5%). Elevated ESR occurred in 51 patients (78%), with a mean of 81 ± 32.2 mm/hr. All received glucocorticoids for 13.1 ± 10 months. Azathioprine, Methotrexate, and Tocilizumab usage was 15.3% (n = 9), 8.5% (n = 5), and 3.4% (n = 2), respectively. Remission was observed in 57.6% (n=34), and 40.7% (n = 24) had a chronic clinical course on treatment. Males had higher biopsy-based diagnoses (p = .008), and biopsy-diagnosed patients were older (p = .043). The literature search yielded only 20 manuscripts originating in the Arab world. The predominant study types included case reports and retrospective analyses, with only one case series and onecase-control study.

Clinical and prognostic differences in oropharyngeal squamous cell carcinoma in USA and Denmark, two HPV high-prevalence areas

BackgroundUncertainty persists regarding clinical and treatment variations crucial to consider when comparing high human papillomavirus (HPV)-prevalence oropharyngeal squamous cell carcinoma (OPSCC) cohorts for accurate patient stratification and replicability of clinical trials across different geographical areas. MethodsOPSCC patients were included from The University of Texas MD Anderson Cancer Center (UTMDACC), USA and from The University Hospital of Copenhagen, Denmark from 2015–2020, (n = 2484). Outcomes were 3-year overall survival (OS) and recurrence-free interval (RFI). Subgroup analyses were made for low-risk OPSCC patients (T1–2N0M0) and high-risk patients (UICC8 III-IV). ResultsThere were significantly more HPV-positive (88.2 % vs. 63.1 %), males (89.4 % vs. 74.1 %), never-smokers (52.1 % vs. 23.7 %), lower UICC8-stage (I/II: 79.3 % vs. 68 %), and fewer patients treated with radiotherapy (RT) alone (14.8 % vs. 30.3 %) in the UTMDACC cohort. No difference in the adjusted OS was observed (hazard ratio [HR] 1.21, p = 0.23), but a significantly increased RFI HR was observed for the Copenhagen cohort (HR: 1.74, p = 0.003). Subgroup analyses of low- and high-risk patients revealed significant clinical and treatment differences. No difference in prognosis was observed for low-risk patients, but the prognosis for high-risk patients in the Copenhagen cohort was worse (OS HR 2.20, p = 0.004, RFI HR 2.80, p = 0.002). ConclusionsWe identified significant differences in clinical characteristics, treatment modalities, and prognosis between a Northern European and Northern American OPSCC population. These differences are important to consider when comparing outcomes and for patient stratification in clinical trials, as reproducibility might be challenging.

Unraveling the Mysteries of Cystic Fibrosis: Causes, Symptoms, and Treatment Strategies

In this work we present the most relevant and important data, so that the reader will be able to identify the disease "Cystic Fibrosis", regardless of the fact that in Mexico this disease is not common, thanks to the fact that in Mexico and in the world newborns are screened. In this way the rate of this disease in Mexico and the world was reduced. In Mexico, there are 350 new cases every year, said the General Director of the National Center for Gender Equity and Reproductive Health, Dr. Ricardo García Cavazos. Thanks to this data, the purpose of this work is to guide readers in the identification of this disease and in this way generate a positive and active influence in the identification of this disease. This disease is a disease that has its historical antecedents since the year 1595, when with the thought of a spell on a girl during her autopsy, the first clinical data that are characteristic of this disease were given. Being in the 70's where with the passage of time and as new knowledge came to what we know today. Cystic fibrosis is an inherited multisystem disorder of children and adults, it is the leading cause of severe chronic lung disease in children. Cystic fibrosis occurs most often in white populations in Northern Europe, North America and Australia/New Zealand and is inherited in an autosomal recessive manner.

A compilation of common crossbill Loxia curvirostraL., 1758 ring-recovery data from the Iberian Peninsula and other European regions

In November 2021, a female common crossbill ringed in Switzerland was found in the Sistema Central mountain range, within the administrative border of the Community of Madrid (Spain). This is an unusal record due to the lack of data on irruptions of this species from central or northern Europe in the centre of the Iberian Peninsula. In this study, we have compiled all the existing common crossbill ring-recovery data from Iberia and other European regions. Our results show that common crossbill populations in the Iberian Peninsula are mainly sedentary, with limited movements across the different pine forest masses in search of food. In contrast, northern European common crossbill populations develop long distance migratory movements that may involve a large number of individuals following a NE-SW axis that, in an irregular manner and depending on the year, can arrive in the Iberian Peninsula in mid-August or September, where they may remain for several years before returning to their places of origin. In the Iberian Peninsula, these crossbills seem to use the pine species available as a trophic resource according to their ecological speciation, including species not present in their regions of origin.

A multi-population approach supports common patterns in marine growth and maturation decision in Atlantic salmon (Salmo salar L.) from southern Europe.

This study provides a regional picture of long-term changes in Atlantic salmon growth at the southern edge of their distribution, using a multi-population approach spanning 49 years and five populations. We provide empirical evidence of salmon life history being influenced by a combination of common signals in the marine environment and population-specific signals. We identified an abrupt decline in growth from 1976 and a more recent decline after 2005. As these declines have also been recorded in northern European populations, our study significantly expands a pattern of declining marine growth to include southern European populations, thereby revealing a large-scale synchrony in marine growth patterns for almost five decades. Growth increments during their sea sojourn were characterized by distinct temporal dynamics. At a coarse temporal resolution, growth during the first winter at sea seemed to gradually improve over the study period. However, the analysis of finer seasonal growth patterns revealed ecological bottlenecks of salmon life histories at sea in time and space. Our study reinforces existing evidence of an impact of early marine growth on maturation decision, with small-sized individuals at the end of the first summer at sea being more likely to delay maturation. However, each population was characterized by a specific probabilistic maturation reaction norm, and a local component of growth at sea in which some populations have better growth in some years might further amplify differences in maturation rate. Differences between populations were smaller than those between sexes, suggesting that the sex-specific growth threshold for maturation is a well-conserved evolutionary phenomenon in salmon. Finally, our results illustrate that although most of the gain in length occurs during the first summer at sea, the temporal variability in body length at return is buffered against the decrease in post-smolt growth conditions. The intricate combination of growth over successive seasons, and its interplay with the maturation decision, could be regulating body length by maintaining diversity in early growth trajectories, life histories, and the composition of salmon populations.

Climate Niche Modeling Reveals the Fate of Pioneering Late Pleistocene Populations in Northern Europe

Climate Niche Modeling Reveals the Fate of Pioneering Late Pleistocene Populations in Northern Europe

Increasing winter temperatures explain body size decrease in wintering bird populations of Northern Europe—But response patterns vary along the spatioclimatic gradient

AbstractAimRecent evidence has shown changes in body size and shape of individuals, which are suggested to be a result of global warming caused by climate change. Here, we explored the spatiotemporal changes in wing length and body mass of 24 wintering bird species in Northern Europe and how these relate to temperature anomaly.LocationFinland and Sweden, Europe.Time Period50 years, 1970 to 2020.Major Taxa StudiedBirds, 24 species.MethodsWe used site‐specific, long‐term winter ringing data containing wing length and body mass measurements from across Sweden and Finland for 24 bird species. We modelled wing length and body mass change over time, in relation to the spatioclimatic gradient and as response to temperature anomalies (of [i] the same winter as the ringing took place, [ii] the previous winter and [iii] the previous spring) by accounting for phylogenetic relatedness between species and their species‐specific responses to each predictor of interest.ResultsWe show that across all species, body size has decreased since the 1970s, with a negative relationship between wing length and temperature anomalies of previous winters, suggesting carry‐over effects likely linked to body size‐related survival or dispersal. Body mass was negatively related to the temperature anomaly of the same winter, indicating more immediate effects related to reduced fat reserves during mild winters.Main ConclusionsOur results highlight a climate‐driven decrease in body size across several species and its association with positive anomalies in winter temperature in the high latitudes. However, the responses are not spatially uniform and there is considerable species‐specific variation, emphasizing the importance of conducting multispecies studies when investigating responses to climate change. The mechanisms of decreasing wing length and body mass seem to differ and underline the immediate and carry‐over effects of temperature warming during the nonbreeding season.

428. PHARYNGEAL SQUAMOUS CELL CARCINOMA AND RISK OF LATER ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract Introduction Pharyngeal squamous cell carcinoma is a known risk factor for later squamous cell carcinoma of the esophagus. We investigated whether the risk of esophageal carcinoma is high enough to justify routine gastroscopy surveillance in a northern European population. If the risk among patients with pharyngeal carcinoma corresponds to the risk among patients with Barretts esophagus of developing adenocarcinoma, it could justify surveillance. Method Histopathology data from pharyngeal and esophageal biopsies obtained 1980–2016 in Sweden’s 28 pathology departments were linked to national population-based healthcare registers. We calculated a subdistribution hazard ratio (HR) comparing the risk of esophageal cancer and death in patients with pharyngeal carcinoma to a matched general population. Result In total 1399 patients with pharyngeal cancer were identified. 344 were excluded due to age under 18 years, previous esophageal cancer, death or cancer within 6 months of diagnosis. Thus, 1055 patients remained. Median follow up time was 5,1 years. 78% were men and median age at diagnosis of pharyngeal cancer was 64 years. Four (0.38%) patients developed esophageal squamous cell carcinoma during follow-up, equal to 1 in 263 patients (HR = 14,32; 95%CI = 1,55-132,30). 855 of the patients (81%) died during follow-up (HR = 7,65; 95% = 6,82-8,59). Discussion The yearly risk of developing esophageal squamous cell carcinoma was 0,07%, which is lower than the risk among patients with Barretts esophagus. Therefore, we find no support for long-term endoscopic surveillance among patients with pharyngeal cancer.

Bronze Diabetes: A Common Genetic Disorder Due to Systemic Iron Overload

In medical science, hemochromatosis is a genetic disorder that is commonly known as bronze diabetes, which is due to continuously over-absorbed of excess iron from the gastrointestinal tract for hepcidin deficiency, and deposited in the liver, pancreas, heart, skin, gonads, pituitary gland, and other organs. Hepcidin regulates the activity of ferroportin, the only identified cellular iron exporter. Hemochromatosis is a relatively new term to common people, and it is named bronze diabetes because of the brown color of the skin due to the accumulation of huge iron in the body. Symptoms and expressions of this disease are hepatic fibrosis, fatigue, arthralgia, cirrhosis, diabetes mellitus, arthropathy, pigmentation, cardiomyopathy, and hepatomegaly. Hemochromatosis is more prevalence among Northern European populations, and five to ten times more common among males than females. Phlebotomy is the popular treatment of this disease to remove iron, and ensures normal survival if applied early, and has been shown recently to reverse hepatic fibrosis but not cirrhosis.

Genetic history of East-Central Europe in the first millennium CE

BackgroundThe appearance of Slavs in East-Central Europe has been the subject of an over 200-year debate driven by two conflicting hypotheses. The first assumes that Slavs came to the territory of contemporary Poland no earlier than the sixth century CE; the second postulates that they already inhabited this region in the Iron Age (IA). Testing either hypothesis is not trivial given that cremation of the dead was the prevailing custom in Central Europe from the late Bronze Age until the Middle Ages (MA).ResultsTo address this problem, we determined the genetic makeup of representatives of the IA Wielbark- and MA Slav-associated cultures from the territory of present-day Poland. The study involved 474 individuals buried in 27 cemeteries. For 197 of them, genome-wide data were obtained. We found close genetic affinities between the IA Wielbark culture-associated individuals and contemporary to them and older northern European populations. Further, we observed that the IA individuals had genetic components which were indispensable to model the MA population.ConclusionsThe collected data suggest that the Wielbark culture-associated IA population was formed by immigrants from the north who entered the region of contemporary Poland most likely at the beginning of the first millennium CE and mixed with autochthons. The presented results are in line with the hypothesis that assumes the genetic continuation between IA and MA periods in East-Central Europe.

GROWING CONDITIONS AND SEED PRODUCTIVITY OF <i>PINGUICULA VULGARIS</i> (LENTIBULARIACEAE) IN LENINGRAD REGION

The growing conditions of Pinguicula vulgaris in the vicinity of the villages Pudost’ (floodplain meadow) and Glyadino (slope meadow, lowland spring fen) in the Leningrad Region were studied in detail, and the seed productivity of its plants was evaluated in these conditions for the first time. Despite a close geographical location and a general confinedness of both populations to the Izhora Upland (to the outcrops of carbonate rocks), they differ in an occupied area and its microtopography, the degree of shading of plants during daylight, and soil moisture (though of similar acidity), and also differ in the species composition of plant communities (richer in Pudost’ than in Glyadino). At the same time, regardless of the differences in growing conditions, the level of seed-setting in P. vulgaris plants in both populations during all the years of research was close and quite high (64–80% in Pudost’, 70–72% in Glyadino), that indicates a high potential for the renewal of the species in the populations by seed propagation. It is noted that the main factors limiting the size of Pinguicula populations in the Leningrad Region are the same as in its other populations of Northern Europe: intense settlement of territories by the species forming a layer with high closeness and height, trampling of soils, unfavorable weather conditions during flowering and fruiting of the plants significantly reducing their seed productivity. However, unlike some subarctic populations of P. vulgaris, where a decrease of seed productivity occurs due to low temperatures at the end of a short growing season and irregular reproduction (especially at the species moving into mountain conditions), in populations of the Leningrad Region (with a longer growing season and regular reproduction), it decreased mainly due to a long dry periods during flowering and fruiting of the plants.

A Benchmark for Atlantic Salmon Conservation: Genetic Diversity and Structure in a Southern European Glacial Refuge before the Climate Changed

Atlantic salmon Salmo salar supports highly valuable commercial and recreational fisheries in Europe, but its stocks are currently overexploited and threatened by climate change. Its southernmost populations (in northern Spain) play a key role in conserving the species’ original genetic diversity, which is endangered due to decades-long (1970s to 1990s) massive stocking with non-native stocks. Their decline is well documented, but the effect of stock transfer and conservation efforts is unclear. Nine microsatellite loci were amplified from archival samples (scales from 1958–1959) from eight Spanish rivers to analyse the species’ natural genetic dynamics before its decline started. Allelic richness was high in the historical populations (the 1950s) and above most contemporary estimates. Private alleles were found in most rivers, indicating high local uniqueness and relative isolation among river basins. Some alleles are regional markers since they are rare or absent from contemporary northern European populations. Effective population size suggested good conservation status, with higher values than those estimated for contemporary populations. Strong population structure and genetic differentiation between rivers were found, with limited gene flow, restricted to geographically close populations. Our estimates of historical genetic diversity and structure from southernmost salmon populations are a powerful benchmark to guide conservation programs.

Increasing winter temperatures explain body size decrease in wintering bird populations of Northern Europe – but response patterns vary along the spatioclimatic gradient

Increasing winter temperatures explain body size decrease in wintering bird populations of Northern Europe – but response patterns vary along the spatioclimatic gradient

Population structure and genetic diversity of Fusarium graminearum from southwestern Russia and the Russian Far East as compared with northern Europe and North America

ABSTRACT Genetic variation at variable number tandem repeat (VNTR) markers was used to assess population structure and diversity among 296 Fusarium graminearum isolates from northern Europe (Finland, northwestern Russia, and Norway), southern Europe (southwestern and western Russia), and Asia (Siberia and the Russian Far East). We identified at least two highly differentiated and geographically structured genetic populations (E1 and E2) in Eurasia (ΦPT = 0.35). Isolates from northern Europe were almost exclusively from the E1 population (95.6%) and had the 3ADON (3-acetyldeoxynivalenol) trichothecene genotype (97.3%). In contrast, all isolates from southern Europe were from the E2 population and 94.4% had the 15ADON (15-acetyldeoxynivalenol) genotype. The E2 population also predominated in the Asian sampling locations (92.7%) where 3ADON and 15ADON genotypes occurred at nearly equal frequencies. Southern European isolates were more closely related to those from Asia (ΦPT = 0.06) than to geographically closer populations from northern Europe (ΦPT ≥ 0.31). Northern European populations also harbored substantially less genetic diversity (Ne ≤ 2.1) than populations in southern Europe or Asia (Ne ≥ 3.4), indicative of a selective sweep or recent introduction and subsequent range expansion in northern Europe. Bayesian analyses incorporating previously described genetic populations from North America (NA1 and NA2) surprisingly identified NA2 and E2 as a single genetic population, consistent with hypotheses of a recent Eurasian origin for NA2. Additionally, more than 10% of the isolates from Asia and southern Europe were assigned to the NA1 population, indicating recent introductions of NA1 into parts of Eurasia. Collectively, these results demonstrate that there are at least three genetic populations of F. graminearum in the Northern Hemisphere and indicate that population-level diversity in Eurasia and North America has been shaped by recent transcontinental introductions.