Highland Populations Research Articles

Whole mitochondrial genome analysis in highland Tibetans: further matrilineal genetic structure exploration.

Introduction: The Qinghai-Tibet Plateau is one of the last terrestrial environments conquered by modern humans. Tibetans are among the few high-altitude settlers in the world, and understanding the genetic profile of Tibetans plays a pivotal role in studies of anthropology, genetics, and archaeology. Methods: In this study, we investigated the maternal genetic landscape of Tibetans based on the whole mitochondrial genome collected from 145 unrelated native Lhasa Tibetans. Molecular diversity indices, haplotype diversity (HD), Tajima's D and Fu's Fs were calculated and the Bayesian Skyline Plot was obtained to determining the genetic profile and population fluctuation of Lhasa Tibetans. To further explore the genetic structure of Lhasa Tibetans, we collected 107 East Asian reference populations to perform principal component analysis (PCA), multidimensional scaling (MDS), calculated Fst values and constructed phylogenetic tree. Results: The maternal genetic landscape of Tibetans showed obvious East Asian characteristics, M9a (28.28%), R (11.03%), F1 (12.41%), D4 (9.66%), N (6.21%), and M62 (4.14%) were the dominant haplogroups. The results of PCA, MDS, Fst and phylogenetic tree were consistent: Lhasa Tibetans clustered with other highland Tibeto-Burman speakers, there was obvious genetic homogeneity of Tibetans in Xizang, and genetic similarity between Tibetans and northern Han people and geographically adjacent populations was found. In addition, specific maternal lineages of Tibetans also be determined in this study. Discussion: In general, this study further shed light on long-time matrilineal continuity on the Tibetan Plateau and the genetic connection between Tibetans and millet famers in the Yellow River Basin, and further revealed that multiple waves of population interaction and admixture during different historical periods between lowland and highland populations shaped the maternal genetic profile of Tibetans.

Characterization of the Spectrum of Mitochondrial DNA Nucleotide Substitutions in Human Populations in High Altitude Environments

Using phylogenetic analysis of the nucleotide sequences of whole mitochondrial genomes (mtDNA), the spectra of germinal nucleotide substitutions (on the L-chain of mtDNA) were reconstructed in highland populations of the Pamirs and Tibet in comparison with regional indigenous groups of West Asia, Northeast Siberia, and South Siberia. No differences were found in the distribution of nucleotide substitution frequencies in the mtDNA spectra depending on the population distribution by altitude. Pyrimidine transitions dominate in all mtDNA spectra, and T → C substitutions are the most frequent among them. Next in frequency in most regional groups are A → G substitutions, but in the Pamir and northeast Asian groups G → A substitutions are prevalent. Of the transversions in all populations studied C → A replacements were found to be predominant, except for the Tibetan one, where A → C substitutions are more frequent. The lack of differences in the distribution of mtDNA mutations in high-altitude and non-highland populations indicates that the structure of mtDNA spectra in human populations is independent of the oxidative stress intensity in mitochondria.

Coping with extremes: Alternations in diet, gut microbiota, and hepatic metabolic functions in a highland passerine

In wild animals, diet and gut microbiota interactions are critical moderators of metabolic functions and are highly contingent on habitat conditions. Challenged by the extreme conditions of high-altitude environments, the strategies implemented by highland animals to adjust their diet and gut microbial composition and modulate their metabolic substrates remain largely unexplored. By employing a typical human commensal species, the Eurasian tree sparrow (Passer montanus, ETS), as a model species, we studied the differences in diet, digestive tract morphology and enzyme activity, gut microbiota, and metabolic energy profiling between highland (the Qinghai-Tibet Plateau, QTP; 3230 m) and lowland (Shijiazhuang, Hebei; 80 m) populations. Our results showed that highland ETSs had enlarged digestive organs and longer small intestinal villi, while no differences in key digestive enzyme activities were observed between the two populations. The 18S rRNA sequencing results revealed that the dietary composition of highland ETSs were more animal-based and less plant-based than those of the lowland ones. Furthermore, 16S rRNA sequencing results suggested that the intestinal microbial communities were structurally segregated between populations. PICRUSt metagenome predictions further indicated that the expression patterns of microbial genes involved in material and energy metabolism, immune system and infection, and xenobiotic biodegradation were strikingly different between the two populations. Analysis of liver metabolomics revealed significant metabolic differences between highland and lowland ETSs in terms of substrate utilization, as well as distinct sex-specific alterations in glycerophospholipids. Furthermore, the interplay between diet, liver metabolism, and gut microbiota suggests a dietary shift resulting in corresponding changes in gut microbiota and metabolic functions. Our findings indicate that highland ETSs have evolved to optimize digestion and absorption, rely on more protein-rich foods, and possess gut microbiota tailored to their dietary composition, likely adaptive physiological and ecological strategies adopted to cope with extreme highland environments.

Sexual dimorphism and ontogenetic variation in the head shape of two neighbouring populations of the common lancehead Bothrops jararaca (Serpentes: Viperidae)

Abstract The head is the most important element in trophic ecology among snakes. Head shape is affected by several factors, both intrinsic, such as size and sex, and extrinsic, such as geographical variation. Often, different populations are subject to different environmental conditions that are reflected in different phenotypes adapted to local conditions. Here, we investigate sexual dimorphism, ontogenetic allometry and environmental effects on head shape in two populations of Bothrops jararaca. We have found a significant effect of sex and population, with females from the highland population having a large braincase region and a more arrow-shaped head. Size increase accounted for a considerable amount of variation in shape, but the coefficient of correlation diverged between populations. Sexual dimorphism in head shape was not found in juveniles, but the ontogenetic trajectory was non-parallel between populations. Rainfall was most associated with a larger snout and reduced braincase. In the genus Bothrops, except in early stages, females often grow faster and attain larger sizes than males, which might affect head shape. Also, possible differences in diet, behaviour and ontogenetic variations between populations might be a reasonable cause of specific allometric trajectories.

The Genomic Basis of Adaptation to High Elevations in Africanized Honey Bees.

A range of different genetic architectures underpin local adaptation in nature. Honey bees (Apis mellifera) in the Eastern African Mountains harbor high frequencies of two chromosomal inversions that likely govern adaptation to this high-elevation habitat. In the Americas, honey bees are hybrids of European and African ancestries and adaptation to latitudinal variation in climate correlates with the proportion of these ancestries across the genome. It is unknown which, if either, of these forms of genetic variation governs adaptation in honey bees living at high elevations in the Americas. Here, we performed whole-genome sequencing of 29 honey bees from both high- and low-elevation populations in Colombia. Analysis of genetic ancestry indicated that both populations were predominantly of African ancestry, but the East African inversions were not detected. However, individuals in the higher elevation population had significantly higher proportions of European ancestry, likely reflecting local adaptation. Several genomic regions exhibited particularly high differentiation between highland and lowland bees, containing candidate loci for local adaptation. Genes that were highly differentiated between highland and lowland populations were enriched for functions related to reproduction and sperm competition. Furthermore, variation in levels of European ancestry across the genome was correlated between populations of honey bees in the highland population and populations at higher latitudes in South America. The results are consistent with the hypothesis that adaptation to both latitude and elevation in these hybrid honey bees are mediated by variation in ancestry at many loci across the genome.

The Differences in Adaptation Between Lowland and Highland Populations

The Differences in Adaptation Between Lowland and Highland Populations

Feeding ecology of a highland population of hamadryas baboons (Papio hamadryas) at Borena-Sayint National Park, northern Ethiopia.

Studying the diet and feeding behavior of primates is essential to understanding their ecology and designing effective conservation plans. Despite decades of study on the hamadryas baboon (Papio hamadryas) in lowland habitats, little is known about the feeding ecology of this species in highland ecosystems. To address this empirical gap, we tracked temporal changes in vegetation abundance and their relation to the dietary choices of hamadryas baboons in highland habitat at Borena-Sayint National Park (BSNP) in northern Ethiopia. We performed behavioral scan sampling on a focal study band of 21-37 hamadryas baboons over a 12-month period. We found that mature and young leaves were the most abundant plant parts throughout the year, while fruits and flowers were the least abundant, with significant seasonal variation that followed the bimodal pattern of rainfall characteristic of the Ethiopian highlands ecosystem. The annual diet of hamadryas baboons at BSNP consisted mostly of fruits (32.0%) and graminoid blades (21.2%), and included 52 food species across 22 families of plants and three families of animals. Food raided from nearby farms accounted for 8.8% of their diet. The availability of fruits and flowers was positively correlated with their consumption, suggesting that these are preferred foods, whereas graminoid blades, and other leaves, appeared to be less preferred foods. The feeding ecology of hamadryas baboons at BSNP differs considerably from that of lowland populations. The well-studied lowland hamadryas baboons in Awash National Park obtain much of their diet from Acacia species and palm fruit, whereas those at BSNP, where Acacia trees are rare and palms are absent, relied on Olinia rochetiana and Rosa abyssinica for a combined 27% of their annual diet. The reliance of hamadryas baboons at BSNP on cultivated crops for nearly one-tenth of their diet leads to conflict with humans and warrants more detailed study so that this issue can be addressed in conservation plans for the area.

Climate change intensified violence in the south-central Andean highlands from 1.5 to 0.5 ka

AbstractThe archaeology of the pre-contact Andes provides an ideal study of human responses to climate change given the region's extreme climatic variability, excellent archaeological preservation, and robust paleoclimate records. We evaluate the effects of climate change on the frequency of interpersonal violence in the south-central Andes from ca. 1.5–0.5 ka (AD 470–1540) by comparing incidents of skeletal trauma observed among 2753 crania from 58 sites to rates of ice accumulation at the Quelccaya Glacier. We find that, in the highlands, the odds of identifying inter-personal violence increase on average by a multiplicative factor of 2.4 (1.8–3.2; 95% C.I.) for every 10-centimeter decrease in annual ice accumulation. Our statistical analysis does not detect a relationship between ice accumulation and interpersonal violence rates among coastal or mid-elevation populations. This disparity likely resulted from variable economic and sociopolitical strategies at different elevations. The failure of rain-fed agriculture during periods of drought and concomitant dissolution of organizing polities likely predisposed highland populations to socioeconomic stress and violent competition for limited resources. Conversely, diversity among lowland and midland economies may have buffered against the effect of drought.

Genetic Adaptation of Siberian Larch (Larix sibirica Ledeb.) to High Altitudes

Forest trees growing in high altitude conditions offer a convenient model for studying adaptation processes. They are subject to a whole range of adverse factors that are likely to cause local adaptation and related genetic changes. Siberian larch (Larix sibirica Ledeb.), whose distribution covers different altitudes, makes it possible to directly compare lowland with highland populations. This paper presents for the first time the results of studying the genetic differentiation of Siberian larch populations, presumably associated with adaptation to the altitudinal gradient of climatic conditions, based on a joint analysis of altitude and six other bioclimatic variables, together with a large number of genetic markers, single nucleotide polymorphisms (SNPs), obtained from double digest restriction-site-associated DNA sequencing (ddRADseq). In total, 25,143 SNPs were genotyped in 231 trees. In addition, a dataset of 761 supposedly selectively neutral SNPs was assembled by selecting SNPs located outside coding regions in the Siberian larch genome and mapped to different contigs. The analysis using four different methods (PCAdapt, LFMM, BayeScEnv and RDA) revealed 550 outlier SNPs, including 207 SNPs whose variation was significantly correlated with the variation of some of environmental factors and presumably associated with local adaptation, including 67 SNPs that correlated with altitude based on either LFMM or BayeScEnv and 23 SNPs based on both of them. Twenty SNPs were found in the coding regions of genes, and 16 of them represented non-synonymous nucleotide substitutions. They are located in genes involved in the processes of macromolecular cell metabolism and organic biosynthesis associated with reproduction and development, as well as organismal response to stress. Among these 20 SNPs, nine were possibly associated with altitude, but only one of them was identified as associated with altitude by all four methods used in the study, a nonsynonymous SNP in scaffold_31130 in position 28092, a gene encoding a cell membrane protein with uncertain function. Among the studied populations, at least two main groups (clusters), the Altai populations and all others, were significantly genetically different according to the admixture analysis based on any of the three SNP datasets as follows: 761 supposedly selectively neutral SNPs, all 25,143 SNPs and 550 adaptive SNPs. In general, according to the AMOVA results, genetic differentiation between transects or regions or between population samples was relatively low, although statistically significant, based on 761 neutral SNPs (FST = 0.036) and all 25,143 SNPs (FST = 0.017). Meanwhile, the differentiation based on 550 adaptive SNPs was much higher (FST = 0.218). The data showed a relatively weak but highly significant linear correlation between genetic and geographic distances (r = 0.206, p = 0.001).

Disparities in COVID-19 incidence and fatality rates at high-altitude.

SARS-CoV-2 has affected every demography disproportionately, including even the native highland populations. Hypobaric-hypoxic settings at high-altitude (HA, >2,500 masl) present an extreme environment that impacts the survival of permanent residents, possibly including SARS-CoV-2. Conflicting hypotheses have been presented for COVID-19 incidence and fatality at HA. To evaluate protection or risk against COVID-19 incidence and fatality in humans under hypobaric-hypoxic environment of high-altitude (>2,501 masl). Global COVID-19 data of March 2020-21, employed from official websites of the Indian Government, John Hopkins University, and Worldometer were clustered into 6 altitude categories. Clinical cofactors and comorbidities data were evaluated with COVID-19 incidence and fatality. Extensive comparisons and correlations using several statistical tools estimated the risk and protection. Of relevance, data analyses revealed four distinct responses, namely, partial risk, total risk, partial protection, and total protection from COVID-19 at high-altitude indicating a mixed baggage and complexity of the infection. Surprisingly, it included the countries within the same geographic region. Moreover, body mass index, hypertension, and diabetes correlated significantly with COVID-19 incidence and fatality rate (P≤0.05). Varied patterns of protection and risk against COVID-19 incidence and fatality were observed among the high-altitude populations. It is though premature to generalize COVID-19 effects on any particular demography without further extensive studies.

Barriers to COVID-19 vaccine acceptance to improve messages for vaccine uptake in indigenous populations in the central highlands of Guatemala: a participatory qualitative study

IntroductionAs of July 2022, a little over one-third of Guatemalans were fully vaccinated. While COVID-19 vaccination rates are not officially reported nationally by racial/ethnic groups, non-governmental organisations and reporters have...

Beyond morphs: Inter-individual colour variation despite strong genetic determinism of colour morphs in a wild bird.

Categorizing individuals into discrete forms in colour polymorphic species can overlook more subtle patterns in coloration that can be of functional significance. Thus, quantifying inter-individual variation in these species at both within- and between-morph levels is critical to understand the evolution of colour polymorphisms. Here we present analyses of inter-individual colour variation in the Reunion grey white-eye (Zosterops borbonicus), a colour polymorphic wild bird endemic to the island of Reunion in which all highland populations contain two sympatric colour morphs, with birds showing predominantly grey or brown plumage, respectively. We first quantified colour variation across multiple body areas by using a continuous plumage colour score to assess variation in brown-grey coloration as well as smaller scale variation in light patches. To examine the possible causes of among-individual variation, we tested if colour variation in plumage component elements could be explained by genotypes at two markers near a major-effect locus previously related to back coloration in this species, and by other factors such as age, sex and body condition. Overall, grey-brown coloration was largely determined by genetic factors and was best described by three distinct clusters that were associated to genotypic classes (homozygotes and heterozygote), with no effect of age or sex, whereas variation in smaller light patches was primarily related to age and sex. Our results highlight the importance of characterizing subtle plumage variation beyond morph categories that are readily observable since multiple patterns of colour variation may be driven by different mechanisms, have different functions and will likely respond in different ways to selection.

Genomic profiling of climate adaptation in Aedes aegypti along an altitudinal gradient in Nepal indicates nongradual expansion of the disease vector.

Driven by globalization, urbanization and climate change, the distribution range of invasive vector species has expanded to previously colder ecoregions. To reduce health-threatening impacts on humans, insect vectors are extensively studied. Population genomics can reveal the genomic basis of adaptation and help to identify emerging trends of vector expansion. By applying whole genome analyses and genotype-environment associations to populations of the main dengue vector Aedes aegypti, sampled along an altitudinal gradient in Nepal (200-1300 m), we identify putatively adaptive traits and describe the species' genomic footprint of climate adaptation to colder ecoregions. We found two differentiated clusters with significantly different allele frequencies in genes associated to climate adaptation between the highland population (1300 m) and all other lowland populations (≤800 m). We revealed nonsynonymous mutations in 13 of the candidate genes associated to either altitude, precipitation or cold tolerance and identified an isolation-by-environment differentiation pattern. Other than the expected gradual differentiation along the altitudinal gradient, our results reveal a distinct genomic differentiation of the highland population. Local high-altitude adaptation could be one explanation of the population's phenotypic cold tolerance. Carrying alleles relevant for survival under colder climate increases the likelihood of this highland population to a worldwide expansion into other colder ecoregions.

Effects of Microplastic on Human Gut Microbiome: Detection of Plastic-Degrading Genes in Human Gut Exposed to Microplastics—Preliminary Study

Microplastics are major pollutants in the environment, and it is currently established that microplastics have already entered human food chains and been incorporated into the human body through ingestion and inhalation. Several works in animal models have already reported the adverse effect of microplastic exposure on biological systems; however, the effect of microplastic contamination on human health is still far from understood. In previous work, we reported microplastic contamination in the digestive tract of the Indonesian coastal and highland population. Using the same stool samples, we extended our previous work by investigating gut microbial composition in samples with and without microplastic contamination using next-generation sequencing. We found that microplastic contamination does not affect overall gut microbial composition and the abundance of gut-health-related genes. However, we found a negative and positive correlation between specific types of microplastics with certain bacterial taxa, especially from the genera Roseburia, Clostridium, and Prevotella. Despite the lack of a profound effect on the gut microbiome, we detected for the first time the presence of genes encoding plastic-degrading enzymes in the human gut microbiome, suggesting an adaptation of gut microbiome to microplastic contamination.

Allele-specific Expression Reveals Multiple Paths to Highland Adaptation in Maize.

Maize is a staple food of smallholder farmers living in highland regions up to 4,000 m above sea level worldwide. Mexican and South American highlands are two major highland maize growing regions, and population genetic data suggest the maize's adaptation to these regions occurred largely independently, providing a case study for convergent evolution. To better understand the mechanistic basis of highland adaptation, we crossed maize landraces from 108 highland and lowland sites of Mexico and South America with the inbred line B73 to produce F1 hybrids and grew them in both highland and lowland sites in Mexico. We identified thousands of genes with divergent expression between highland and lowland populations. Hundreds of these genes show patterns of convergent evolution between Mexico and South America. To dissect the genetic architecture of the divergent gene expression, we developed a novel allele-specific expression analysis pipeline to detect genes with divergent functional cis-regulatory variation between highland and lowland populations. We identified hundreds of genes with divergent cis-regulation between highland and lowland landrace alleles, with 20 in common between regions, further suggesting convergence in the genes underlying highland adaptation. Further analyses suggest multiple mechanisms contribute to this convergence in gene regulation. Although the vast majority of evolutionary changes associated with highland adaptation were region specific, our findings highlight an important role for convergence at the gene expression and gene regulation levels as well.

Hidden in the highs: Two new species of the enigmatic toadheaded pitvipers of the genus Bothrocophias

Bothrocophias microphthalmus (Cope, 1875) currently comprises most mid- to highland populations of the genus Bothrocophias in the eastern versant of the Andes. We describe two new species of Bothrocophias from the highlands of the Colombian Andes previously referred to as B. microphthalmus based on morphological and genetic evidence. Our phylogenetic analysis revealed that B. micropthalmus as currently recognized is paraphyletic with respect to B. hyoprora, and the two new taxa are sister lineages. These new toadheaded pitvipers can be morphologically distinguished from their congeners based on the presence of contact between the internasal scales, the number of prefoveal scales, the presence of a lacunolabial scale, the arrangement of supralabial scales, ventral scale counts, the color pattern of the dorsal and ventral surfaces of the body and tail, and hemipenial morphology. We discuss some possible taxonomic scenarios for the lineages found within the B. microphthalmus species complex but refrain from making additional taxonomic changes given our reduced sampling of the southern lineages.

VALUE OF ECHOCARDIOGRAPHY AND CHEST CT IMAGING IN PATIENTS WITH HIGH-ALTITUDE PULMONARY HYPERTENSION

SESSION TITLE: Late Breaking Pulmonary Vascular Disease PostersSESSION TYPE: Original Investigation PostersPRESENTED ON: 10/18/2022 01:30 pm - 02:30 pmPURPOSE: This study aimed to evaluate the value of echocardiography and chest computed tomography in patients with high altitude pulmonary hypertension.METHODS:Retrospective cohort studies were performed to compare echocardiographic and chest CT-related parameters in the HAPH group, the RHC-excluded PH group and the control population, and to detect their correlation with mPAP using Pearson analysis and Spearman analysis. Binary logistic regression analysis was performed to predict the diagnostic value of dPA, rPA, TR and their combination in the HAPH population. Receiver operating characteristic (ROC) curve analysis was used to identify the optimal SUV max cutoff value.RESULTS:A total of 89 cases in the clinically suspected HAPH population were included from January 2015 to January 2022. Correlation analysis showed that mPAP was positively correlated with TR and sPAP, and mPAP was positively correlated with dPA and rPA. In the control group, age was positively correlated with dAA. In the echocardiographic test, the most suitable TR cut-off value for differentiating HAPH from RHC-excluded PH was 3.21 (sensitivity 75.5%, specificity 80.6%, AUC = 0.834) according to ROC curve analysis; in the CT test, the most suitable dPA cut-off value was 34.41 (sensitivity 75.5%, specificity 83.3%, AUC = 0.831); the AUC for TR combined with dPA was 0.889, sensitivity and specificity 84.9% and 80.6%, respectively; in the CT assay, the best dPA cut-off value to distinguish HAPH from control according to ROC curve analysis was 29.82 mm ( sensitivity of 84.9%, specificity of 94.9%, AUC = 0.956); the optimal rPA cut-off value for distinguishing HAPH from controls was 0.95 (sensitivity of 88.7%, specificity of 88.1%, AUC = 0.942).CONCLUSIONS:We established optimal TR, dPA cut-off values and TR combined with dPA diagnostic efficacy for discriminating RHC-excluded PH patients from HAPH with a high degree of accuracy.CLINICAL IMPLICATIONS:Our study found a moderate correlation between mPAP and rPA, DPA and TR in a highland population with pulmonary hypertension. Chest CT and echocardiography can be used as primary screening methods for people with pulmonary hypertension, and the combination of the two leads to improved diagnostic outcomes.DISCLOSURES:No relevant relationships by Lu GuoNo relevant relationships by Yicen HanNo relevant relationships by xing he SESSION TITLE: Late Breaking Pulmonary Vascular Disease Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: 10/18/2022 01:30 pm - 02:30 pm PURPOSE: This study aimed to evaluate the value of echocardiography and chest computed tomography in patients with high altitude pulmonary hypertension. METHODS: Retrospective cohort studies were performed to compare echocardiographic and chest CT-related parameters in the HAPH group, the RHC-excluded PH group and the control population, and to detect their correlation with mPAP using Pearson analysis and Spearman analysis. Binary logistic regression analysis was performed to predict the diagnostic value of dPA, rPA, TR and their combination in the HAPH population. Receiver operating characteristic (ROC) curve analysis was used to identify the optimal SUV max cutoff value. RESULTS: A total of 89 cases in the clinically suspected HAPH population were included from January 2015 to January 2022. Correlation analysis showed that mPAP was positively correlated with TR and sPAP, and mPAP was positively correlated with dPA and rPA. In the control group, age was positively correlated with dAA. In the echocardiographic test, the most suitable TR cut-off value for differentiating HAPH from RHC-excluded PH was 3.21 (sensitivity 75.5%, specificity 80.6%, AUC = 0.834) according to ROC curve analysis; in the CT test, the most suitable dPA cut-off value was 34.41 (sensitivity 75.5%, specificity 83.3%, AUC = 0.831); the AUC for TR combined with dPA was 0.889, sensitivity and specificity 84.9% and 80.6%, respectively; in the CT assay, the best dPA cut-off value to distinguish HAPH from control according to ROC curve analysis was 29.82 mm ( sensitivity of 84.9%, specificity of 94.9%, AUC = 0.956); the optimal rPA cut-off value for distinguishing HAPH from controls was 0.95 (sensitivity of 88.7%, specificity of 88.1%, AUC = 0.942). CONCLUSIONS: We established optimal TR, dPA cut-off values and TR combined with dPA diagnostic efficacy for discriminating RHC-excluded PH patients from HAPH with a high degree of accuracy. CLINICAL IMPLICATIONS: Our study found a moderate correlation between mPAP and rPA, DPA and TR in a highland population with pulmonary hypertension. Chest CT and echocardiography can be used as primary screening methods for people with pulmonary hypertension, and the combination of the two leads to improved diagnostic outcomes. DISCLOSURES: No relevant relationships by Lu Guo No relevant relationships by Yicen Han No relevant relationships by xing he

Morphological variation in the common lancehead populations: Sexual dimorphism and ontogenetic patterns

AbstractThe common lancehead Bothrops jararaca is widespread in the Atlantic Forest in Brazil. The species is known to show a marked sexual dimorphism pattern, with the female being larger than the male. However, most efforts in clarifying morphological variation between the sexes are often focused on a single population. In this paper, we investigate how sexual dimorphism and ontogenetic trajectories vary among populations as well as the ontogenetic trajectories of B. jararaca. We analyzed 211 specimens from a coastal and a highland population and measured 17 morphological traits, including linear and meristic characteristics, and the analysis revealed a clear but variable effect of sex and population. Females were larger than males in all evaluated populations. Furthermore, females in the coastal population were generally smaller than in the highland population but had significantly more scales. Widespread species often experience differential environmental pressures even in terms of biotic and abiotic factors. We attribute the results found herein to specificities in prey availability and climatic conditions which affect the ontogenetic pattern between the sexes and the populations, resulting in specific sexual dimorphism patterns.

Repeated genetic adaptation to altitude in two tropical butterflies

Repeated evolution can provide insight into the mechanisms that facilitate adaptation to novel or changing environments. Here we study adaptation to altitude in two tropical butterflies, Heliconius erato and H. melpomene, which have repeatedly and independently adapted to montane habitats on either side of the Andes. We sequenced 518 whole genomes from altitudinal transects and found many regions differentiated between highland (~ 1200 m) and lowland (~ 200 m) populations. We show repeated genetic differentiation across replicate populations within species, including allopatric comparisons. In contrast, there is little molecular parallelism between the two species. By sampling five close relatives, we find that a large proportion of divergent regions identified within species have arisen from standing variation and putative adaptive introgression from high-altitude specialist species. Taken together our study supports a role for both standing genetic variation and gene flow from independently adapted species in promoting parallel local adaptation to the environment.

New Insight into Genetic Structure and Diversity of Scots Pine (Pinus sylvestris L.) Populations in Lithuania Based on Nuclear, Chloroplast and Mitochondrial DNA Markers

We studied the genetic differentiation, structure, and diversity of Scots pine populations in Lithuania based on nuclear, chloroplast microsatellite, and mitochondrial DNA markers. We focused on revealing evolutionary history, country-wide geneflow patterns, and structuring among the Scots pine populations. We genotyped 439 Scots pine individuals of mature age from 23 natural Scots pine stands in Lithuania and used the AMOVA and a set of genetic-clustering methods. The among-population differentiation was weak for nuclear microsatellite loci (nSSRs) (FST = 0.005) but much stronger for cpSSRs (PhiST = 0.240). The populations were structured into highland and lowland populations based on cpSSRs and eastern highland versus the rest for nSSRs. We detected two mtDNA mitotypes—the universal type A and northeastern type B, and the latter occurred at a markedly higher frequency in eastern Lithuania. Within-population genetic diversity was higher in large pine-dominated forest tracts in the eastern highlands than in fragmented forests in the western highlands. We concluded that phenology-based genetic networks following the temperature climate gradients have a strong effect on shaping the genetic structure of otherwise rather homogeneous gene pools of Scots pine populations in Lithuania. The possible effects of human interference with forests on genetic diversity of Scots pine populations in Lithuania are discussed.