Human CCDC51 and yeast Mdm33 are functionally conserved mitochondrial inner membrane proteins that demarcate a subset of organelle fission events.

Mitochondria are highly dynamic double membrane-bound organelles that exist in a semi-continuous network. Mitochondrial morphology arises from the complex interplay of numerous processes, including opposing fission and fusion dynamics and the formation of highly organized cristae invaginations of the inner membrane. While extensive work has examined the mechanisms of mitochondrial fission, it remains unclear how fission is coordinated across two membrane bilayers and how mitochondrial inner membrane organization is coupled with mitochondrial fission dynamics. Previously, the yeast protein Mdm33 was implicated in facilitating fission by coordinating with inner membrane homeostasis pathways. However, Mdm33 is not conserved outside fungal species and its precise mechanistic role remains unclear. Here, we use a bioinformatic approach to identify a putative structural ortholog of Mdm33 in humans, CCDC51 (also called MITOK). We find that the mitochondrial phenotypes associated with altered CCDC51 levels implicate the protein in mitochondrial fission dynamics. Further, using timelapse microscopy, we spatially and temporally resolve Mdm33 and CCDC51 to a subset of mitochondrial fission events. Finally, we show that CCDC51 can partially rescue yeast Δmdm33 cells, indicating the proteins are functionally analogous. Our data reveal that Mdm33/CCDC51 are conserved mediators of mitochondrial morphology and suggest the proteins play a crucial role in maintaining normal mitochondrial dynamics and organelle homeostasis.

Effect of durian peel fiber on thermal, mechanical, and biodegradation characteristics of thermoplastic cassava starch composites.

This study is focused on developing and enhancing the properties of durian peel fiber (DPF) reinforced thermoplastic cassava starch (TPCS) composites. The proposed DPF was extracted from agro-waste and incorporated into TPCS with various contents of DPF (10, 20, 30, 40, and 50 wt%) via compression molding. The mechanical and thermal characteristics of the fabricated composites were studied. The thermal properties of the biocomposite were improved with the addition of DPF, as evidenced by an increase in the material's thermal stability and indicated by a higher onset decomposition temperature. The integration of DPF into TPCS improved the biodegradation rate process of the composites. Besides, the results indicated that incorporating DPF in TPCS composites enhanced tensile and flexural properties, with a 40 wt% DPF content exhibited the highest modulus and strength. The tensile and flexural strengths of TPCS/DPF composites were raised significantly from 2.96 to 21.89 MPa and 2.5 to 35.0 MPa, respectively, compared to the control TPCS sample, as DPF increased from 0 to 40 wt%. This finding was consistent with Fourier-Transform Infrared (FT-IR) spectroscopy and scanning electron micrograph (SEM), which showed good interaction between DPF and TPCS matrix. The analysis revealed that DPF at a 40 wt% ratio was the best composition compared to the other ratio. Finally, based on improved results, DPF was identified as a potential resource of green reinforcement for the biodegradable TPCS matrix.

Development of an intravenous low-dose buprenorphine initiation protocol.

BACKGROUND: Buprenorphine is a life-saving treatment for opioid use disorder (OUD). Low-dose initiation (LDI) is an emerging buprenorphine initiation strategy that circumvents barriers associated with standard initiation. This study aims to describe tolerability and completion of LDI using intravenous (IV) buprenorphine and to define dosing protocols in a cohort of patients hospitalized in an urban academic hospital. METHODS: Data was collected via retrospective chart review for IV buprenorphine LDI cases initiated between September 1, 2020 and February 28, 2021. Cases were excluded if diagnostic criteria for OUD was not met, Clinical Opiate Withdrawal Scale (COWS) scores were not recorded, or sublingual (SL) buprenorphine was given within 24 h before IV buprenorphine. Completion of LDI and COWS data were assessed for all cases. Cases were categorized based on adherence to a dosing strategy and LDI indication, including OUD and acute pain, non-prescribed fentanyl exposure, and transition from methadone. RESULTS: Seventy-two cases were identified, and thirteen cases were excluded, leaving 59 cases in the population. Of these cases, 72.9% (43/59) tolerated LDI, and 91.5% (54/59) completed buprenorphine initiation. Forty-four (44/59, 75%) cases were adherent. Median duration of LDI within the adherent group was 23.7 h (IQR 22.8-27.0), 37.1 h (IQR 36.2-40.9), and 48.8 h (IQR 47.0-52.4) for the "rapid," "moderate," and "slow" dosing strategies, respectively. CONCLUSIONS: IV buprenorphine LDI was tolerated and completed in a majority of patients. Dosing protocols allowed for rapid transition to sublingual buprenorphine. Acute pain or recent methadone or fentanyl exposure may inform IV LDI dosing strategy selection.

Inpatient Early Intervention for Serious Mental Illnesses Is Associated With Fewer Rehospitalizations Compared With Treatment as Usual in a High-volume Public Psychiatric Hospital Setting.

OBJECTIVE: High-acuity publicly funded inpatient psychiatric settings usually feature short lengths of stay and high readmission rates. This study examined the influence of an early intervention program for serious mental illnesses (SMI) on readmissions at 6 and 12 months postdischarge at a high-volume, urban public inpatient psychiatric hospital. METHODS: The Early Onset Treatment Program (EOTP) is a cost-free, 90-day inpatient multidisciplinary service intervention program for uninsured patients who are within 5 years of SMI onset, funded as a pilot program by the Texas state legislature. Rehospitalization rates at 6 and 12 months were extracted from electronic medical records for EOTP participants (n=165) and comparison patients matched on demographics and diagnosis (n=155). The comparison group received treatment as usual at the same psychiatric hospital. Group re-admission rates were compared using logistic and Poisson regression analyses. RESULTS: Group membership was a significant predictor of rehospitalization (P<0.0001) at both 6 and 12 months. Expressed as 1/odds ratio (OR), the EOTP group was less likely to readmit once and more than once at 6 months postdischarge (1/OR=3.82 and 4.74, respectively) compared with the non-EOTP group. The EOTP group was also less likely to readmit once and more than once at 12 months postdischarge (1/OR=2.96 and 3.51, respectively). CONCLUSIONS: The results suggest that participation in the EOTP service in this high-acuity setting was significantly related to reduced likelihood of rehospitalization at 6 and 12 months. Several variables may account for this observation, including length of stay, longer medication adherence, environmental stability, and more individualized and extensive psychotherapy treatment.

Customizing Early Intervention Treatment for Psychosis in the UTHealth - Harris County Psychiatric Center.

High-need, high-cost patients include those with diagnosed serious mental illnesses (e.g., schizophrenia; SMI). They often delay or fail to seek treatment. If they receive treatment, care is often sought from generalist settings (e.g., primary care or emergency medicine) or is suboptimal due to the provision of limited, non-evidence-based intervention and lack of communication, integration, and coordination among providers. This results in high aggregate costs and poor outcomes. Value-based health care requires care coordination to address the medical and social needs of this population. We describe a unique early intervention program for SMI that emanates from an inpatient setting: The Early Onset Treatment Program (EOTP) at the University of Texas Health Science Center at Houston-Harris County Psychiatric Center. The EOTP offers free, phase-specific, multidisciplinary treatment to young adults without health insurance with the aim of improving their long-term outcomes and reducing the rate of rehospitalization. An evaluation of the EOTP indicates program participants were significantly less likely to be rehospitalized at six months (4.73 times less likely) and at 12 months (3.5 times less likely) than a comparison group (p <.001), and participants' scores of symptomatology and disability significantly decreased following treatment.

Inpatient early intervention for serious mental illnesses and post-discharge criminal involvement in a high-volume psychiatric hospital setting.

Individuals with serious mental illness (SMI) are at increased risk for arrest and incarceration relative to the same-community population without SMI. Publicly-funded inpatient psychiatric hospitals usually feature short lengths of stay and limited opportunities for extended services that might impact criminal justice involvement after discharge. This study examined the influence of an early intervention program for SMI at a high-volume public psychiatric hospital on involvement in the criminal justice system post-discharge. The Early Onset Treatment Program (EOTP) is an extended service intervention program for uninsured patients who are within 5 years of SMI onset. Criminal justice records (number of arrests with conviction, days of incarceration) were obtained for EOTP participants (n = 164) and comparison patients (n = 164) matched on demographics, diagnosis, and discharge date via propensity score matching. Data were zero-inflated and analyzed using hurdle models, controlling for prior arrests. The EOTP group was less likely to be convicted of at least one crime post-discharge (0 arrests vs. > 0, p < .001), and spent fewer days incarcerated (if incarcerated ≥1 day, p < .03). Participation in the EOTP service was linked to reduced likelihood of post-discharge arrest and days incarcerated. Several alternative variables may contribute to this preliminary observation, including length of stay, medication adherence, longer environmental stability, and individual patient characteristics.

Microtubules are necessary for proper Reticulon localization during mitosis.

During mitosis, the structure of the Endoplasmic Reticulum (ER) displays a dramatic reorganization and remodeling, however, the mechanism driving these changes is poorly understood. Hairpin-containing ER transmembrane proteins that stabilize ER tubules have been identified as possible factors to promote these drastic changes in ER morphology. Recently, the Reticulon and REEP family of ER shaping proteins have been shown to heavily influence ER morphology by driving the formation of ER tubules, which are known for their close proximity with microtubules. Here, we examine the role of microtubules and other cytoskeletal factors in the dynamics of a Drosophila Reticulon, Reticulon-like 1 (Rtnl1), localization to spindle poles during mitosis in the early embryo. At prometaphase, Rtnl1 is enriched to spindle poles just prior to the ER retention motif KDEL, suggesting a possible recruitment role for Rtnl1 in the bulk localization of ER to spindle poles. Using image analysis-based methods and precise temporal injections of cytoskeletal inhibitors in the early syncytial Drosophila embryo, we show that microtubules are necessary for proper Rtnl1 localization to spindles during mitosis. Lastly, we show that astral microtubules, not microfilaments, are necessary for proper Rtnl1 localization to spindle poles, and is largely independent of the minus-end directed motor protein dynein. This work highlights the role of the microtubule cytoskeleton in Rtnl1 localization to spindles during mitosis and sheds light on a pathway towards inheritance of this major organelle.

Hospital-to-Home Interventions, Use, and Satisfaction: A Meta-analysis.

CONTEXT: Hospital-to-home transitions are critical opportunities to promote patient safety and high-quality care. However, such transitions are often fraught with difficulties associated with increased health care use and poor patient satisfaction. OBJECTIVE: In this review, we determine which pediatric hospital discharge interventions affect subsequent health care use or parental satisfaction compared with usual care. DATA SOURCES: We searched 7 bibliographic databases and 5 pediatric journals. STUDY SELECTION: Inclusion criteria were: (1) available in English, (2) focused on children <18 years of age, (3) pediatric data reported separately from adult data, (4) not focused on normal newborns or pregnancy, (5) discharge intervention implemented in the inpatient setting, and (6) outcomes of health care use or caregiver satisfaction. Reviews, case studies, and commentaries were excluded. DATA EXTRACTION: Two reviewers independently abstracted data using modified Cochrane data collection forms and assessed quality using modified Downs and Black checklists. RESULTS: Seventy one articles met inclusion criteria. Although most interventions improved satisfaction, interventions variably reduced use. Interventions focused on follow-up care, discharge planning, teach back-based parental education, and contingency planning were associated with reduced use across patient groups. Bundled care coordination and family engagement interventions were associated with lower use in patients with chronic illnesses and neonates. LIMITATIONS: Variability limited findings and reduced generalizability. CONCLUSIONS: In this review, we highlight the utility of a pediatric discharge bundle in reducing health care use. Coordinating follow-up, discharge planning, teach back-based parental education, and contingency planning are potential foci for future efforts to improve hospital-to-home transitions.

Trial of labor and vaginal delivery rates in women with a prior cesarean.

OBJECTIVE: To evaluate evidence on trial of labor (TOL) and vaginal delivery rates in women with a prior cesarean and to understand the characteristics of women offered a trial of labor. DATA SOURCES: MEDLINE, DARE, and Cochrane databases were searched for articles evaluating mode of delivery for women with a prior cesarean delivery published between 1980 and September 2009. STUDY SELECTION: Studies were included if they involved human participants, were in English, conducted in the United States or in developed countries, and if they were rated fair or good base on U.S. Preventive Services Task Force (USPSTF) criteria. DATA EXTRACTION AND SYNTHESIS: The search yielded 3,134 abstracts: 69 full-text papers on TOL and vaginal birth after cesarean (VBAC) rates and 10 on predictors of TOL. The TOL rate in U.S. studies was 58% (95% CI [52, 65]) compared with 64% (95% CI [59, 70]) in non U.S. STUDIES: The TOL rate in the U.S. was 62% (95% CI [57, 66]) for studies completed prior to 1996 and dropped to 44% (95% CI [34, 53]) in studies launched after 1996, p = .016. In U.S. studies, 74% (95% CI [72, 76]) of women who had a TOL delivered vaginally. Women who had a prior vaginal birth or delivered at a large teaching hospital were more likely to be offered a TOL. CONCLUSIONS: Although the TOL rate has dropped since 1996, the rate of vaginal delivery after a TOL has remained constant. Efforts to increase rates of TOL will depend on patients understanding the risks and benefits of both options. Maternity providers are well positioned to provide key education and counseling when patients are not informed of their options.

The Atlantic-Mediterranean watershed, river basins and glacial history shape the genetic structure of Iberian poplars.

Recent phylogeographic studies have elucidated the effects of Pleistocene glaciations and of Pre-Pleistocene events on populations from glacial refuge areas. This study investigates those effects in riparian trees (Populus spp.), whose particular features may convey enhanced resistance to climate fluctuations. We analysed the phylogeographic structure of 44 white (Populus alba), 13 black (Populus nigra) and two grey (Populus x canescens) poplar populations in the Iberian Peninsula using plastid DNA microsatellites and sequences. We also assessed fine-scale spatial genetic structure and the extent of clonality in four white and one grey poplar populations using nuclear microsatellites and we determined quantitative genetic differentiation (Q(ST) ) for growth traits in white poplar. Black poplar displayed higher regional diversity and lower differentiation than white poplar, reflecting its higher cold-tolerance. The dependence of white poplar on phreatic water was evidenced by strong differentiation between the Atlantic and Mediterranean drainage basins and among river basins, and by weaker isolation by distance within than among river basins. Our results suggest confinement to the lower river courses during glacial periods and moderate interglacial gene exchange along coastlines. In northern Iberian river basins, white poplar had lower diversity, fewer private haplotypes and larger clonal assemblies than in southern basins, indicating a stronger effect of glaciations in the north. Despite strong genetic structure and frequent asexual propagation in white poplar, some growth traits displayed adaptive divergence between drainage and river basins (Q(ST) >F(ST)), highlighting the remarkable capacity of riparian tree populations to adapt to regional environmental conditions.

Pediatric educational needs assessment for urban and rural emergency medical technicians.

OBJECTIVE: The objective of the study was to identify past experiences, present needs, barriers, and desired methods of training for urban and rural emergency medical technicians. METHODS: This 62-question pilot-tested written survey was administered at the 2008 Oregon EMS and 2009 EMS for Children conferences. Respondents were compared with registration lists and the state emergency medical services (EMS) database to assess for nonresponder bias. Agencies more than 10 miles from a population of 40,000 were defined as rural. RESULTS: Two hundred nineteen (70%) of 313 EMS personnel returned the surveys. Respondents were 3% first responders, 27% emergency medical technician basics, 20% intermediates, and 47% paramedics. Sixty-eight percent were rural, and 32% were urban. Sixty-eight percent reported fewer than 10% pediatric transports. Overall, respondents rated their comfort caring for pediatric patients as 3.1 on a 5-point Likert scale (95% confidence interval, 3.1-3.2). Seventy-two percent reported a mean rating of less than "comfortable" (4 on the scale) across 17 topics in pediatric care, which did not differ by certification level. Seven percent reported no pediatric training in the last 2 years, and 76% desired more. The "quality of available trainings" was ranked as the most important barrier to training; 26% of rural versus 7% of urban EMS personnel ranked distance as the most significant barrier (P < 0.01). Fifty-one percent identified highly realistic simulations as the method that helped them learn best. In the past 2 years, 19% had trained on a highly realistic pediatric simulator. One to 3 hours was the preferred duration for trainings. CONCLUSIONS: Except for distance as a barrier, there were no significant differences between urban and rural responses. Both urban and rural providers desire resources, in particular, highly realistic simulation, to address the infrequency of pediatric transports and limited training.

Climatic niche and neutral genetic diversity of the six Iberian pine species: a retrospective and prospective view.

Quaternary climatic fluctuations have left contrasting historical footprints on the neutral genetic diversity patterns of existing populations of different tree species. We should expect the demography, and consequently the neutral genetic structure, of taxa less tolerant to particular climatic extremes to be more sensitive to long-term climate fluctuations. We explore this hypothesis here by sampling all six pine species found in the Iberian Peninsula (2464 individuals, 105 populations), using a common set of chloroplast microsatellite markers, and by looking at the association between neutral genetic diversity and species-specific climatic requirements. We found large variation in neutral genetic diversity and structure among Iberian pines, with cold-enduring mountain species (Pinus uncinata, P. sylvestris and P. nigra) showing substantially greater diversity than thermophilous taxa (P. pinea and P. halepensis). Within species, we observed a significant positive correlation between population genetic diversity and summer precipitation for some of the mountain pines. The observed pattern is consistent with the hypotheses that: (i) more thermophilous species have been subjected to stronger demographic fluctuations in the past, as a consequence of their maladaptation to recurrent glacial cold stages; and (ii) altitudinal migrations have allowed the maintenance of large effective population sizes and genetic variation in cold-tolerant species, especially in more humid regions. In the light of these results and hypotheses, we discuss some potential genetic consequences of impending climate change.

Low temperature during winter elicits differential responses among populations of the Mediterranean evergreen cork oak (Quercus suber).

Populations of cork oak (Quercus suber L.) were assessed for seasonal and inter-population variability in, and temperature responses of, the ratio between light-induced variable and maximum fluorescence of chlorophyll, Fv/Fm, considered a surrogate for the maximum photochemical efficiency of photosystem II (PSII). Seedlings from 10 populations throughout the distribution range of Q. suber in the Mediterranean basin were grown in a common garden in central Spain. The Fv/Fm ratio of dark-adapted leaves was measured at dawn every month for 2 years. Air temperature was recorded at a nearby climatic station. During the summer, when maximum air temperatures reached 40 degrees C, there were no significant differences in Fv/Fm among populations, but significant differences were seen during the winter. In colder months, Fv/Fm ranged in all populations between 0.5-0.6 and 0.2-0.3 in 2001 and 2002, respectively. The variance explained by the population effect was greatest during winter months, especially in 2002, reaching a peak value of 10% when minimum air temperature was below -10 degrees C. Populations originating from warmer sites showed the largest decline in Fv/Fm between the end of 2001 and the beginning of 2002. Thus, a negative linear relationship was established between mean annual temperature at the population source and population mean Fv/Fm recorded in the coldest month in 2002 and normalized by the Fv/Fm spring measurement.

Increased selfing and correlated paternity in a small population of a predominantly outcrossing conifer, Pinus sylvestris.

Outcrossing rate, the rates of ovule and seed abortion, and levels of correlated paternity were estimated in a small population of Pinus sylvestris, a predominantly outcrossing conifer, and were compared with estimates from two widely dispersed woodlands of the same species, showing a range of densities. On average, seed trees of the small population showed an eight-fold higher selfing rate (25 vs. 3%) and a 100-fold greater incidence of correlated paternity (19.6 vs. 0.2%) than did trees from the large populations. No evidence was found of pollen limitation within the remnant stand, as suggested by ovule abortion rates. Investigation of the mating patterns in the small population, based on the unambiguous genealogy of 778 open-pollinated seeds, showed a large departure from random mating. Only 8% of the possible mating pairs within the stand were observed. Correlated paternity rate within a maternal sibship was negatively associated (rs = -0.398, P < 0.050) with the distance to the nearest neighbour, and shared paternity among maternal sibships was negatively correlated (rs = -0.704, P < 0.001) with the distance between seed trees. Numerical simulations, based on the estimated individual pollen dispersal kernel, suggest that restricted dispersal might have been the key factor affecting mating patterns in the small population and, together with low population density, may account for the observed mating system variation between the small and the large populations. The results of this study show that a severe size reduction may substantially affect the mating system of a wind-pollinated, typically outcrossed plant species.

Cross-amplification and sequence variation of microsatellite loci in Eurasian hard pines.

Microsatellite transfer across coniferous species is a valued methodology because de novo development for each species is costly and there are many species with only a limited commodity value. Cross-species amplification of orthologous microsatellite regions provides valuable information on mutational and evolutionary processes affecting these loci. We tested 19 nuclear microsatellite markers from Pinus taeda L. (subsection Australes) and three from P. sylvestris L. (subsection Pinus) on seven Eurasian hard pine species ( P. uncinata Ram., P. sylvestris L., P. nigra Arn., P. pinaster Ait., P. halepensis Mill., P. pinea L. and P. canariensis Sm.). Transfer rates to species in subsection Pinus (36-59%) were slightly higher than those to subsections Pineae and Pinaster (32-45%). Half of the trans-specific microsatellites were found to be polymorphic over evolutionary times of approximately 100 million years (ten million generations). Sequencing of three trans-specific microsatellites showed conserved repeat and flanking regions. Both a decrease in the number of perfect repeats in the non-focal species and a polarity for mutation, the latter defined as a higher substitution rate in the flanking sequence regions close to the repeat motifs, were observed in the trans-specific microsatellites. The transfer of microsatellites among hard pine species proved to be useful for obtaining highly polymorphic markers in a wide range of species, thereby providing new tools for population and quantitative genetic studies.

Population genetic structure in a Mediterranean pine (Pinus pinaster Ait.): a comparison of allozyme markers and quantitative traits.

F-statistics were employed to analyse quantitative and allozyme variation among 19 native populations of maritime pine (Pinus pinaster Ait.). Fourteen polymorphic allozyme loci were used to provide an empirical basis for constructing a null hypothesis to test natural selection as a determinant of quantitative evolution in stem form, total height growth and survival at 30 years old. Hidden biases, that may result in a difference between quantitative (Q(ST)) and allozyme (F(ST)) differentiation which are not because of the action of natural selection, were avoided by comparing pairs of populations using linear models. All quantitative traits showed higher differentiation than allozymes. The highest divergence was found in stem form, whereas divergences in total height and survival were significantly lower. Differential adaptation to regional and local patterns of precipitation, temperature and soil type seem to be the best explanation of the different structure found in quantitative traits and allozyme loci. Possible bias in the estimation of Q(ST) due to the level of quantitative within-population diversity and the role of adaptation of maritime pine after the last glaciation to highly diverse ecological conditions are discussed with special reference to the actual geographical structure of gene diversity in the species' native range.

Seed gene flow and fine-scale structure in a Mediterranean pine ( Pinus pinaster Ait.) using nuclear microsatellite markers.

The Mediterranean populations of maritime pine ( Pinus pinaster Ait.) are typically small and have a scattered distribution, being threatened by human activities and forest fires. In the framework of the genetic-resources conservation program of this species, a native multi-age stand located in a Mediterranean area (central Spain) was studied using three highly polymorphic nuclear microsatellites (SSRs). Spatial autocorrelation analysis was conducted using Moran's index in order to detect fine-scale structure in both natural regeneration and mature trees. The spatial pattern of seed flow based on dispersed progeny was studied using a highly reliable subset of parent-offspring matches obtained by means of parentage analysis and simulation-based calculation of statistical confidence. Maritime pine showed a fine-scale structure at the seedling stage. In natural regeneration, the autocorrelograms indicated a patch size of approximately 10 m. The fine-scale structure seems to be produced by a restricted seed gene flow. In fact, there was an excess of parent-offspring matches in a radius of 15 m from the parent trees. Pines with a heavy seed, such as P. pinaster, are expected to have a short dispersal distance, thus producing a fine-scale structure. However, the fine-scale structure did not persist in the mature trees. Within-population genetic structure in Mediterranean pines may be affected by a number of post-dispersal events (e.g. mortality due to the severity of the Mediterranean climate and animal-mediated secondary dispersal during the summer period). Thus, great alteration in the pattern produced by the initial seed rain and differences in genetic structure between tree cohorts are expected.

Patterns of variation at a mitochondrial sequence-tagged-site locus provides new insights into the postglacial history of European Pinus sylvestris populations.

Due to their maternal mode of inheritance, mitochondrial markers can be regarded as almost 'ideal' tools in evolutionary studies of conifer populations. In the present study, polymorphism was analysed at one mitochondrial intron (nad 1, exon B/C) in 23 native European Pinus sylvestris populations. In a preliminary screening for variation using a polymerase chain reaction-restriction fragment length polymorphism approach, two length variants were identified. By fully sequencing the 2.5 kb region, the observed length polymorphism was found to result from the insertion of a 31 bp sequence, with no other mutations observed within the intron. A set of primers was designed flanking the observed mutation, which identified a novel sequence-tagged-site mitochondrial marker for P. sylvestris. Analysis of 747 trees from the 23 populations using these primers revealed the occurrence of two distinct haplotypes in Europe. Within the Iberian Peninsula, the two haplotypes exhibited extensive population differentiation (PhiST = 0.59; P < or = 0.001) and a marked geographical structuring. In the populations of central and northern Europe, one haplotype largely predominated, with the second being found in only one individual of one population.