Discordant Patterns Research Articles

Impact of Guideline-Discordant Treatment on Cost and Health Care Utilization in Older Adults with Early-Stage Breast Cancer.

National Comprehensive Cancer Network (NCCN) guideline-based treatment is a marker of high-quality care. The impact of guideline discordance on cost and health care utilization is unclear. This retrospective cohort study of Medicare claims data from 2012 to 2015 included women age ≥65 with stage I-III breast cancer receiving care within the University of Alabama at Birmingham Cancer Community Network. Concordance with NCCN guidelines was assessed for treatment regimens. Costs to Medicare and health care utilization were identified from start of cancer treatment until death or available follow-up. Adjusted monthly cost and utilization rates were estimated using linear mixed effect and generalized linear models. Of 1,177 patients, 16% received guideline-discordant treatment, which was associated with nonwhite race, estrogen receptor/progesterone receptor negative, human epidermal growth receptor 2 (HER2) positive, and later-stage cancer. Discordant therapy was primarily related to reduced-intensity treatments (single-agent chemotherapy, HER2-targeted therapy without chemotherapy, bevacizumab without chemotherapy, platinum combinations without anthracyclines). In adjusted models, average monthly costs for guideline-discordant patients were $936 higher compared with concordant (95% confidence limits $611, $1,260). For guideline-discordant patients, adjusted rates of emergency department visits and hospitalizations per thousand observations were 25% higher (49.9 vs. 39.9) and 19% higher (24.0 vs. 20.1) per month than concordant patients, respectively. One in six patients with early-stage breast cancer received guideline-discordant care, predominantly related to undertreatment, which was associated with higher costs and rates of health care utilization. Additional randomized trials are needed to test lower-toxicity regimens and guide clinicians in treatment for older breast cancer patients. Previous studies lack details about types of deviations from chemotherapy guidelines that occur in older early-stage breast cancer patients. Understanding the patterns of guideline discordance and its impact on patient outcomes will be particularly important for these patients. This study found 16% received guideline-discordant care, predominantly related to reduced intensity treatment and associated with higher costs and rates of health care utilization. Increasing older adult participation in clinical trials should be a priority in order to fill the knowledge gap about how to treat older, less fit patients with breast cancer.

Influence of Wolbachia infection on mitochondrial DNA variation in the genus Polytremis (Lepidoptera: Hesperiidae)

The maternally inherited obligate bacteria Wolbachia is known for infecting the reproductive tissues of a wide range of arthropods and can contribute to phylogenetically discordant patterns between mtDNA and nDNA. In this study, we tested for an association between mito-nuclear discordance in Polytremis and Wolbachia infection. Six of the 17 species of Polytremis were found to be infected with Wolbachia. Overall, 34% (70/204) of Polytremis specimens were Wolbachia positive and three strains of Wolbachia identified using a wsp marker were further characterized as six strains based on MLST markers. Wolbachia acquisition in Polytremis appears to occur mainly through horizontal transmission rather than codivergence based on comparison of the divergence times of Wolbachia and Polytremis species. At the intraspecific level, one of the Wolbachia infections (wNas1) is associated with reduced mtDNA polymorphism in the infected Polytremis population. At the interspecific level, there is one case of mito-nuclear discordance likely caused by introgression of P. fukia mtDNA into P. nascens driven by another Wolbachia strain (wNas3). Based on an absence of infected males, we suspect that one Wolbachia strain (wNas2) affects sex ratio, but the phenotypic effects of the other strains are unclear. These data reveal a dynamic interaction between Polytremis and Wolbachia endosymbionts affecting patterns of mtDNA variation.

Ancestral polymorphisms explain the role of chromosomal inversions in speciation.

Understanding the role of chromosomal inversions in speciation is a fundamental problem in evolutionary genetics. Here, we perform a comprehensive reconstruction of the evolutionary histories of the chromosomal inversions in Drosophila persimilis and D. pseudoobscura. We provide a solution to the puzzling origins of the selfish Sex-Ratio arrangement in D. persimilis and uncover surprising patterns of phylogenetic discordance on this chromosome. These patterns show that, contrary to widely held views, all fixed chromosomal inversions between D. persimilis and D. pseudoobscura were already present in their ancestral population long before the species split. Our results suggest that patterns of higher genomic divergence and an association of reproductive isolation genes with chromosomal inversions may be a direct consequence of incomplete lineage sorting of ancestral polymorphisms. These findings force a reconsideration of the role of chromosomal inversions in speciation, not as protectors of existing hybrid incompatibilities, but as fertile grounds for their formation.

Intraspecific mitogenomics of three marine species-at-risk: Atlantic, spotted, and northern wolffish (Anarhichasspp.)

High-resolution mitogenomics of within-species relationships can answer such phylogeographic questions as how species survived the most recent glaciation, as well as identify contemporary factors such as physical barriers, isolation, and gene flow. We examined the mitogenomic population structure of three at-risk species of wolffish: Atlantic (Anarhichas lupus), spotted (A. minor), and northern (A. denticulatus). These species are extensively sympatric across the North Atlantic but exhibit very different life history strategies, a combination that results in concordant and discordant patterns of genetic variation and structure. Wolffish haplogroups were not structured geographically: Atlantic and spotted wolffish each comprised three shallow clades, whereas northern wolffish comprised two deeper but unstructured lineages. We suggest that wolffish species survived in isolation in multiple glacial refugia, either refugia within refugia (Atlantic and spotted wolffish) or more distant refugia (northern wolffish), followed by secondary admixture upon post-glacial recolonisation of the North Atlantic.

A High Quality Genome for Mus spicilegus, a Close Relative of House Mice with Unique Social and Ecological Adaptations.

Genomic data for the closest relatives of house mice (Mus musculus species complex) are surprisingly limited. Here, we present the first complete genome for a behaviorally and ecologically unique member of the sister clade to house mice, the mound-building mouse, Mus spicilegus. Using read cloud sequencing and de novo assembly we produced a 2.50 Gbp genome with a scaffold N50 of 2.27 Mbp. We constructed >25 000 gene models, of which the majority had high homology to other Mus species. To evaluate the utility of the M. spicilegus genome for behavioral and ecological genomics, we extracted 196 vomeronasal receptor (VR) sequences from our genome and analyzed phylogenetic relationships between M. spicilegus VRs and orthologs from M. musculus and the Algerian mouse, M. spretus. While most M. spicilegus VRs clustered with orthologs in M. musculus and M. spretus, 10 VRs with evidence of rapid divergence in M. spicilegus are strong candidate modulators of species-specific chemical communication. A high quality assembly and genome for M. spicilegus will help to resolve discordant ancestry patterns in house mouse genomes, and will provide an essential foundation for genetic dissection of phenotypes that distinguish commensal from non-commensal species, and the social and ecological characteristics that make M. spicilegus unique.

Is Age Trumping Genetic Profiling in Clinical Practice? Relationship of Chemotherapy Recommendation and Oncotype DX Recurrence Score in Patients Aged < 50 Years versus ≥ 50Years, and Trends Over Time.

OncotypeDX (oDX) is used to predict recurrence and indicate response to chemotherapy in patients with early-stage breast cancer (BC). We evaluated the relationship between age (< 50 vs. ≥ 50years), recurrence score (RS), chemotherapy use, and trends of oDX testing over time. Using the National Cancer Database, we identified women with T1/T2, N0, estrogen receptor-positive BC from 2009 to 2014. We stratified patients by age (< 50 and ≥ 50years) and RS (low: < 18; intermediate: 18-30; and high: > 30), and compared demographics, tumor characteristics, and chemotherapy recommendations. Management trends were also assessed. From 2009 to 2014, a total of 377,725 cases met the eligibility criteria for oDX testing; 115,052 (30.5%) patients had oDX, and 60,804 (16.1%) were < 50years of age. The majority had low RS and T1N0 disease. Patients < 50years of age were more likely to be recommended chemotherapy than those ≥ 50years of age, regardless of RS (p ≤ 0.001), and were more likely to ultimately undergo chemotherapy (p < 0.001). When stratified by year, oDX utilization increased. There was a decreasing trend in chemotherapy recommendations in both the low- and intermediate-RS groups for both age groups (all p = 0.001), with no change in the high-RS group (< 50years: p = 0.52; ≥ 50years: p = 0.67). Univariate and multivariate analyses demonstrated that patients < 50years of age and those with a higher RS were more likely to be recommended chemotherapy (p < 0.001). The testing of oDX in BC has significantly increased since first implemented. Results from additional studies such as TAILORx will clarify the current discordant practice patterns between low oDX RSs and adjuvant chemotherapy recommendations.

Improved identification of concordant and discordant gene expression signatures using an updated rank-rank hypergeometric overlap approach

Recent advances in large-scale gene expression profiling necessitate concurrent development of biostatistical approaches to reveal meaningful biological relationships. Most analyses rely on significance thresholds for identifying differentially expressed genes. We use an approach to compare gene expression datasets using ‘threshold-free’ comparisons. Significance cut-offs to identify genes shared between datasets may be too stringent and may miss concordant patterns of gene expression with potential biological relevance. A threshold-free approach gaining popularity in several research areas, including neuroscience, is Rank–Rank Hypergeometric Overlap (RRHO). Genes are ranked by their p-value and effect size direction, and ranked lists are compared to identify significantly overlapping genes across a continuous significance gradient rather than at a single arbitrary cut-off. We have updated the previous RRHO analysis by accurately detecting overlap of genes changed in the same and opposite directions between two datasets. Here, we use simulated and real data to show the drawbacks of the previous algorithm as well as the utility of our new algorithm. For example, we show the power of detecting discordant transcriptional patterns in the postmortem brain of subjects with psychiatric disorders. The new R package, RRHO2, offers a new, more intuitive visualization of concordant and discordant gene overlap.

Inhibitory control in typically developing preschoolers: Relations among temperament, respiratory sinus arrhythmia, and behavior at age 4.

Although inhibitory control (IC) is associated with children's positive adjustment, we know relatively little about factors underlying its development. We examined whether baseline and on-task respiratory sinus arrhythmia [(RSA); a physiological measure of self-regulation] and private speech (a behavioral measure of self-regulation) interacted to confer differences on directly observed IC in 52 typically developing 4-year olds. We found that baseline RSA moderated the association between private speech and IC, such that private speech positively predicted IC in children with relatively higher baseline RSA, but was unrelated to IC in children with relatively lower RSA. We also found that children with a concordant physiological-behavioral pattern (i.e., high RSA and high private speech; low RSA and low private speech) had higher IC, higher effortful control, and lower negative emotionality than those with a discordant physiological-behavioral pattern (i.e., high RSA and low private speech; low RSA and high private speech). Individual differences in physiological and behavioral self-regulation indices may represent distinct regulation pathways that interact to confer differences in IC during the preschool years.

What is Difficult about Grammatical Gender? Evidence from Heritage Russian

The paper examines the role of lexical, morphological, and discourse-referential factors in gender assignment with animate nouns in heritage Russian in order to explore the extent to which these different interfaces are challenging in heritage language acquisition. The analysis of concordant and discordant agreement patterns with nouns representing each type of gender categorization mechanism points to unequal difficulty associated with different types of gender allocation strategies. In particular, heritage speakers converge with baseline speakers in rating possible and impossible agreement combinations in the presence of fixed and transparent lexical and morphological gender categorization cues; however, they display non-target-like judgments of unmarked and underspecified forms characterized by variable agreement behavior (i.e., hybrid nouns and common gender nouns). Problems with forms whose gender reference is disambiguated at the level of discourse point to the syntax-discourse interface as a locus of systematic difficulty for heritage language speakers.

Treatment target re-classification of subjects comparing estimation of low-density lipoprotein cholesterol by the Friedewald equation and direct measurement of LDL-cholesterol

Aims: To compare low-density lipoprotein cholesterol (LDL-C) values calculated by the Friedewald equation with direct LDL-C in patient samples and assess the possible impact on re-classification of LDL-C target values for primary prevention or high cardiovascular disease (CVD) risk (<2.5 mmol/L) and secondary prevention or very high CVD risk (<1.8 mmol/L). LDL-C is an important CVD risk factor. Over the last decade, there has been a change in laboratory methodology from indirectly calculated LDL-C with the Friedewald equation to direct LDL-C measurements (dLDL-C).Methods: Reported results for plasma triglycerides, total cholesterol, high-density lipoprotein-cholesterol, and dLDL-C from 34,981 samples analyzed in year 2014 were extracted from the laboratory information system, Uppsala University Hospital, Uppsala, Sweden.Results: dLDL-C was approximately 10% lower than the corresponding LDL-C results calculated by the Friedewald equation in both men and women. In subjects with triglyceride concentrations above 4 mmol/L (n = 1250) the same discordant pattern was seen as for the entire study population. Altogether 5469 out of 18,051 men (30.3%) and 4604 out of 16,928 women (27.2%) were down-classified at least one CVD risk category. A very small number of subject was up-classified, in total 37 out of 18,051 men (0.2%) and 28 out of 16,928 women (0.2%).Conclusions: The two LDL-C methods had a high concordance, but the direct LDL-C measurement consistently gave approx. 10% lower values, and this caused one-third of subjects to be re-classified as having a lower cardiovascular disease risk in relation to recommended LDL-C target values and decision limits.

Highlights From the Circulation Family of Journals

Highlights From the <i>Circulation</i> Family of Journals

Phylogeny and Evolution of the Neotropical Radiation of Lachemilla (Rosaceae): Uncovering a History of Reticulate Evolution and Implications for Infrageneric Classification

Reticulate evolution often leads to incongruence between nuclear and plastid phylogenies, and comparisons between them have been used as a first approximation to disentangle patterns of hybridization. Because other processes like incomplete lineage sorting and phylogenetic error also produce similar incongruence patterns, additional sources of evidence must be incorporated. Here we focus on reconstructing the phylogeny of Lachemilla (Rosaceae) using nuclear ribosomal ITS and plastid trnL-FDNAsequences, and explore widespread patterns of cytonuclear discordance in this group. Lachemilla is a highly morphologically variable group of perennial herbs and shrubs, and a nearly ubiquitous member of the diverse Neotropical high-altitude grasslands. Our analyses identified four major clades within Lachemilla that are in part congruent with previous morphological classifications of the group. Furthermore, using multiple sources of evidence, including a procrustean approach to cophylogeny estimation, coalescent-based simulations, phylogenetic networks, chromosome counts, and genome size estimations, we also revealed a large-scale pattern of incongruence between the plastid and nuclear phylogenies in Lachemilla, which is mainly the result of widespread hybridization and polyploidy.We also estimated that the origin of Lachemilla in South America (;14.5 MYA) predates the “rapid-uplift” diversification model that has been suggested for other high species-richness Andean plant clades, but following the formation of the high-elevation Andean grasslands during the last 5 MYA, a rapid accumulation of particular nested lineages has contributed to the ubiquitous presence of Lachemilla in these biomes.

UNHEALTHY WEIGHT IN INDIAN FAMILIES: THE ROLE OF THE FAMILY ENVIRONMENT IN THE CONTEXT OF THE NUTRITION TRANSITION.

India faces a dual burden of increasing obesity and persistent underweight as it experiences the nutrition transition-the dietary and lifestyle changes that accompany globalization, economic development, and technological change. Yet, the nutrition transition is not solely a top-down process; rather, global forces converge with local practices at multiple levels of the social ecology. The family environment, a key site for the transmission of local customs and norms, remains largely unexplored in India. We examined the extent to which opposite-gender siblings and mother-child pairs were concordant or discordant in body weight, and whether domains of the family environment, specifically, food practices, food-related gender norms, and household resources, were associated with patterns of unhealthy weight within and between families. Multilevel dyadic analysis and logistic regression were conducted using survey data from a representative sample of 400 families in a Southern Indian city. We identified substantial clustering of weight among opposite-gender sibling pairs (ICC=0.43) and mother-child pairs, as well as important patterns of discordance, including 11% of families experiencing a dual burden of underweight and overweight. Household resources, including mother's education and income, were salient in explaining the distribution of body weight within and between families. Importantly, less examined domains of the family environment were also relevant, including food practices (e.g. grocery shopping frequency), and food-related gender norms (e.g. mother's control of food served at home). Continued exploration of how global and local practices converge in households will be necessary to develop programming that effectively addresses India's dual burden of unhealthy weight.

Interspecies introgressive hybridization in spiny frogs Quasipaa (Family Dicroglossidae) revealed by analyses on multiple mitochondrial and nuclear genes.

Introgression may lead to discordant patterns of variation among loci and traits. For example, previous phylogeographic studies on the genus Quasipaa detected signs of genetic introgression from genetically and morphologically divergent Quasipaa shini or Quasipaa spinosa. In this study, we used mitochondrial and nuclear DNA sequence data to verify the widespread introgressive hybridization in the closely related species of the genus Quasipaa, evaluate the level of genetic diversity, and reveal the formation mechanism of introgressive hybridization. In Longsheng, Guangxi Province, signs of asymmetrical nuclear introgression were detected between Quasipaa boulengeri and Q. shini. Unidirectional mitochondrial introgression was revealed from Q. spinosa to Q. shini. By contrast, bidirectional mitochondrial gene introgression was detected between Q. spinosa and Q. shini in Lushan, Jiangxi Province. Our study also detected ancient hybridizations between a female Q. spinosa and a male Q. jiulongensis in Zhejiang Province. Analyses on mitochondrial and nuclear genes verified three candidate cryptic species in Q. spinosa, and a cryptic species may also exist in Q. boulengeri. However, no evidence of introgressive hybridization was found between Q. spinosa and Q. boulengeri. Quasipaa exilispinosa from all the sampling localities appeared to be deeply divergent from other communities. Our results suggest widespread introgressive hybridization in closely related species of Quasipaa and provide a fundamental basis for illumination of the forming mechanism of introgressive hybridization, classification of species, and biodiversity assessment in Quasipaa.

Discordances in ER, PR, and HER2 between primary breast cancer and brain metastasis

When distant metastases are discovered, it is important to determine receptor profiles of these lesions through histologic examination. However, brain metastasis sites are difficult to reach to be routinely biopsied. The purpose of this study was to determine expression profiles of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) in breast cancer brain metastasis (BCBM) and the existence of discordance between primary breast cancer and brain metastasis. A total of 37 patients who underwent craniotomies for metastatic brain tumors arising from breast cancer at National Cancer Center (NCC) of Korea between 2002 and 2014 were retrospectively reviewed. Clinicopathologic data were collected from electronic medical records. Receptor profiles of primary breast cancer and brain metastasis in each patient were identified. Data of ER, PR, and HER2 expression in brain metastasis were available in electronic medical records for 21 (56.8%) of 37 cases. Results of ER, PR, and HER2 expression were positive in 47.6, 42.9, and 38.1% of patients with brain metastasis, respectively. Receptor conversion occurred in 11 (52.4%) of 21 patients (for ER, 9.5%; for PR, 38.1%; for HER2, 23.8%). Overall survival was longer in patients with concordant receptor expression patterns between primary breast cancer and brain lesion compared to that in patients with discordant patterns. However, such difference was not statistically significant (discordant vs. concordant median survival: 19.2 versus 31.1 months, p = 0.181). Receptor conversion in BCBMs was observed in over 50% of Korean patients used in this study. HER2 conversion was observed in 23.8% of patients in this study. Therefore, if resistance to anti-HER2 treatment is suspected in patients with BCBM, biopsy is needed to determine receptor profiles of brain lesion.

Early Attachment Network with Mother and Father: An Unsettled Issue

AbstractInfants’ patterns of attachment to their mothers and fathers influence important developmental outcomes. Studies suggest that infants form discordant attachment patterns to mothers and fathers, and stress the importance of assessing infants’ parental attachment relationships to evaluate their integrative effects on how they function later in life. However, such studies are few, based on small samples, and not well‐designed longitudinally. Moreover, mixed results on how infants’ attachment patterns to mothers and fathers affect important developmental outcomes have resulted in theoretical inconsistencies regarding the model that best describes the organization of multiple attachment relationships and their effect on later development. In this article, we review research on the unsettled issue of infants’ network of attachment to mothers and fathers, and propose explanatory models that can be tested empirically; the methods we suggest are more robust and innovative than those that have been used traditionally.

HER2 expression patterns in paired primary and metastatic endometrial cancer lesions

Background:Despite successful implementation of drugs targeting the human epidermal growth factor receptor 2 (HER2) receptor in breast and gastric cancers, the potential of HER2 as a therapeutic target in other cancers has been less studied, including endometrial cancer. We investigated expression levels of HER2 (ERBB2) in a large cohort of endometrial cancer lesions, also including complex atypical hyperplasia and metastatic lesions.Methods:67 precursor lesions, 790 primary endometrial cancers and 383 metastatic lesions were investigated for HER2 expression in relation to clinicopathologic features and outcome. Protein levels were assessed by immunohistochemistry (using the HercepTest and staining index (SI) criteria), mRNA levels by microarrays and amplification status by chromogenic in situ hybridisation.Results:High HER2 protein levels were significantly associated with features of aggressive disease and increased mRNA ERBB2 levels. HER2 expression defined by the SI proved to be a better predictor of survival compared with the HercepTest. A discordant HER2 expression pattern between paired primary and metastatic lesions was detected, revealing substantial reduction in HER2 expression from primary to metastatic disease.Conclusions:Loss of HER2 expression is common in metastatic endometrial cancer lesions and assessment of HER2 levels in the metastatic lesions may be important to define the potential benefit of anti-HER2 treatments in endometrial cancer patients.

Divergent clades or cryptic species? Mito-nuclear discordance in a Daphnia species complex

BackgroundGenetically divergent cryptic species are frequently detected by molecular methods. These discoveries are often a byproduct of molecular barcoding studies in which fragments of a selected marker are used for species identification. Highly divergent mitochondrial lineages and putative cryptic species are even detected in intensively studied animal taxa, such as the crustacean genus Daphnia. Recently, eleven such lineages, exhibiting genetic distances comparable to levels observed among well-defined species, were recorded in the D. longispina species complex, a group that contains several key taxa of freshwater ecosystems. We tested if three of those lineages represent indeed distinct species, by analyzing patterns of variation of ten nuclear microsatellite markers in six populations.ResultsWe observed a discordant pattern between mitochondrial and nuclear DNA, as all individuals carrying one of the divergent mitochondrial lineages grouped at the nuclear level with widespread, well-recognized species coexisting at the same localities (Daphnia galeata, D. longispina, and D. cucullata).ConclusionsA likely explanation for this pattern is the introgression of the mitochondrial genome of undescribed taxa into the common species, either in the distant past or after long-distance dispersal. The occurrence of highly divergent but rare mtDNA lineages in the gene pool of widespread species would suggest that hybridization and introgression in the D. longispina species complex is frequent even across large phylogenetic distances, and that discoveries of such distinct clades must be interpreted with caution. However, maintenance of ancient polymorphisms through selection is another plausible alternative that may cause the observed discordance and cannot be entirely excluded.

The latitudinal diversity gradient in New World swallowtail butterflies is caused by contrasting patterns of out‐of‐ and into‐the‐tropics dispersal

AbstractAimThe aim was to determine processes driving the latitudinal diversity gradient (LDG) in New World swallowtail butterfly diversity. We tested three mechanisms commonly invoked to explain the LDG: ecological opportunity, evolutionary rates and biogeographical history.LocationNew World and Eurasia.Time periodOligocene–Present.Major taxa studiedNew World swallowtail butterfly clade (Papilio: Agehana, Alexanoria, Chilasa, Heraclides and Pterourus).MethodsWe integrated data from the most complete current phylogeny of this clade with geographical distributions of each species inferred from ecological niche models (ENMs). We tested for correlation between breadth of available abiotic ecological niche space, latitude and differential rates of diversification between tropical and non‐tropical lineages. The clade's history of climatic and geographical occupancy was also reconstructed using both continuous ancestral character reconstructions and biogeographical history inferred under a dispersal–extinction–cladogenesis model. We considered both latitudinal and climatic definitions of tropicality in our reconstructions.ResultsThere was no strong support for ecological opportunity or macroevolutionary processes as latitudinal diversity gradient drivers. Instead, we recovered discordant patterns in phylogenetic reconstructions of latitudinal geographical range and suitable abiotic climate conditions. Heraclides are likely to have originated and diversified in climatically and latitudinally tropical environments before some lineages dispersed to temperate habitats. The Alexanoria + Chilasa + Pterourus clade is likely to have originated in climatically and latitudinally temperate habitat before dispersing and diversifying; some lineages are likely to have dispersed into the latitudinal tropics via highland temperate‐analogue environments.Main conclusionsThe LDG in New World swallowtails results from complex interactions between ecological niche evolution and biogeographical history; both out‐of‐the‐tropics and into‐the‐tropics processes have contributed to the LDG. Our results present an example where temperate zones appear to be a source, instead of a sink, for biodiversity. Our results emphasize the need to consider biogeographical history not only from the perspective of shifts in geographical space, but also in terms of constraints enforced by ecological niche conservatism.

Comparative phylogeography of a vulnerable bat and its ectoparasite reveals dispersal of a non-mobile parasite among distinct evolutionarily significant units of the host

Knowledge about phylogeographical structuring and genetic diversity is of key importance for the conservation of endangered species. Comparative phylogeography of a host and its parasite has the potential to reveal cryptic dispersal and behaviour in both species, and can thus be used to guide conservation management. In this study, we investigate the phylogeographic structure of the Bechstein’s bat, Myotis bechsteinii, and its ectoparasitic bat fly, Basilia nana, at 12 sites across their entire distribution. For both species, a mitochondrial sequence fragment (ND1 and COI respectively) and nuclear microsatellite genotypes (14 and 10 loci respectively) were generated and used to compare the phylogeography of host and parasite. Our findings confirm the presence of three distinct genetic subpopulations of the Bechstein’s bat in (1) Europe, (2) the Caucasus and (3) Iran, which remain isolated from one another. The genetic distinctiveness of host populations in the Caucasus region and Iran emphasize that these populations must be managed as distinct evolutionarily significant units. This phylogeographical pattern is however not reflected in its parasite, B. nana, which shows evidence for more recent dispersal between host subpopulations. The discordant genetic pattern between host and parasite suggest that despite the long-term genetic isolation of the different host subpopulations, long-range dispersal of the parasite has occurred more recently, either as the result of secondary contact in the primary host or via secondary host species. This indicates that a novel pathogenic threat to one host subpopulation may be able to disperse, and thus have important consequences for all subpopulations.