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Cancer statistics for Asian American, Native Hawaiian, and Pacific Islander people, 2026.

BACKGROUND: Cancer statistics for Asian American and Native Hawaiian and Pacific Islander (NHPI) people are usually aggregated, masking substantial variation within this heterogeneous population. Herein, the American Cancer Society reports cancer incidence and survival for 8 Asian American and 3 NHPI ethnic groups. METHODS: The authors used population-based cancer registry data from the National Cancer Institute's Surveillance, Epidemiology, and End Results program, for Asian American and NHPI ethnic groups from 2000 through 2022. RESULTS: During 2018-2022, overall cancer incidence ranged from 218.3 per 100,000 Kampuchean people to 474.5 per 100,000 Native Hawaiian people, which was 1.5 times higher than the rate for the aggregated Asian American and NHPI population (307.3 per 100,000). High incidence among Native Hawaiian people is largely driven by the highest rates of female breast, colorectal, and prostate cancers, whereas infection-related cancers were highest among Asian American ethnic groups. For example, liver and stomach cancer incidence is highest among Vietnamese (22.2 per 100,000) and Korean people (17.8 per 100,000), respectively, both of which were nearly twice that in Native Hawaiian people (12.9 and 9.6 per 100,000, respectively). Native Hawaiian and Samoan women are twice and 3 times as likely, respectively, to be diagnosed with uterine corpus cancer as aggregated Asian American and NHPI women or White women. Five-year relative survival ranges from 42% in Laotians to 74% in Asian Indians/Pakistanis, with largest differences for colorectal (43% in Laotians to 72% in Asian Indians/Pakistanis) and prostate (63% in Kampucheans to 97% in Japanese) cancers. CONCLUSIONS: Wide variation in cancer risk within the Asian American and NHPI population highlights the critical need for disaggregated data to effectively target cancer prevention and control interventions.

Adolescent

Variability in β-human chorionic gonadotropin concentrations following evacuation of a hydatidiform mole pregnancy: A retrospective cohort study from Vietnam.

BackgroundGestational trophoblastic disease refers to a group of tumors defined by abnormal trophoblastic proliferation. This disease produces a distinct tumor marker, beta-human chorionic gonadotropin, which can be useful for diagnosis and follow-up. The objective of this study was to investigate the variations in serum beta-human chorionic gonadotropin levels after uterine evacuation as well and the progression of gestational trophoblastic neoplasia.Materials and methodsThis retrospective cohort study was conducted at Tu Du Hospital, Vietnam, between January 2019 and December 2020. All patients diagnosed with molar pregnancy were analyzed retrospectively based on serial serum beta-human chorionic gonadotropin levels following uterine evacuation. Post-evacuation outcomes, including relapsed molar pregnancy and gestational trophoblastic neoplasia, were also monitored.ResultsWe enrolled 560 patients with molar pregnancy, including 298 with complete hydatidiform mole and 262 with partial hydatidiform mole. Severe symptoms were more common in those with complete hydatidiform mole. Over the follow-up period, 97 cases of gestational trophoblastic neoplasia were noted. The data show that the median time to gestational trophoblastic neoplasia diagnosis was 8.75&#x2009;&#xb1;&#x2009;4.41 (4-26) weeks. In terms of variations in the serum beta-human chorionic gonadotropin levels, the generalized estimating equation model showed a faster decline in the complete hydatidiform mole group than in the partial hydatidiform mole group. Similarly, regression in serum beta-human chorionic gonadotropin levels was significantly more rapid in patients who progressed to gestational trophoblastic neoplasia than in those with relapsed molar pregnancy (-11,593 vs. -20,651.22 and -12,946.26 vs. -46,329.23 mUI/mL, p&#x2009;<&#x2009;0.001).ConclusionsSurveillance of serum beta-human chorionic gonadotropin levels remains essential for gestational trophoblastic neoplasia monitoring in patients with molar pregnancy following surgical evacuation. The post-evacuation serum beta-human chorionic gonadotropin level regression curve helps distinguish gestational trophoblastic neoplasia from hydatidiform moles. Further evidence is required to strengthen these findings.

Humans

Adolescent health across Asia Pacific, 2000-23: a systematic analysis for the Global Burden of Disease Study 2023.

BACKGROUND: The Asia Pacific region is home to more than half of the world's 1&#xb7;93 billion adolescents (aged 10-24 years). Addressing adolescent health in this region is of global importance, but to date a systematic analysis of key contributors to disease in adolescents has not been done, which is a barrier to responsive action. This systematic analysis of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2023 aims to provide a comprehensive assessment of adolescent health across the Asia Pacific region, at both the subregional and national levels, encompassing burden of disease, mortality, and prevalence of adolescent risk factors. METHODS: As part of GBD 2023, we obtained estimates for cause-specific mortality, disability-adjusted life-years (DALYs), and risk factor prevalence by sex for adolescents aged 10-24 years and 5-year age groups (10-14 years, 15-19 years, and 20-24 years) across 44 countries and territories (hereafter referred to collectively as Asia Pacific), grouped by seven UN subregions, from 2000 to 2023. We extracted GBD 2023 population counts and estimates of number and rate (per 100&#x2008;000 population) for mortality and disease burden (DALYs). Risk prevalence estimates were obtained directly from the Institute for Health Metrics and Evaluation, and binge drinking estimates were sourced from WHO. Estimates are reported with 95% uncertainty intervals (UIs) where possible. UIs were estimated by running 250 draws of the posterior distribution, ordering the draws, and selecting the 2&#xb7;5th and 97&#xb7;5th percentiles for each metric. FINDINGS: In 2023, in adolescents across Asia Pacific, there were 637&#x2008;496 deaths and a total disease burden of 115&#xb7;8 million DALYs, representing 34&#xb7;1% of global adolescent deaths and 40&#xb7;6% of the global adolescent burden of disease. Non-communicable diseases (NCDs; particularly mental disorders) were the leading causes of disease burden and mortality (64&#xb7;8% of DALYs and 43&#xb7;9% of deaths). Unintentional and transport injuries were also leading causes of death (14&#xb7;7% of deaths due to transport injury and 13&#xb7;3% of deaths due to unintentional injury) and leading causes of disease burden particularly among males in south-eastern Asia. In Melanesia, Micronesia, and some parts of south-eastern Asia (Cambodia, Indonesia, Laos, the Philippines, and Timor-Leste), respiratory infections and tuberculosis remained important contributors. Southern Asia had the largest reduction (1&#xb7;5% per year) in all-cause DALYs over the study period, and Australia and New Zealand (0&#xb7;2% per year) had the smallest, with females in Australia and New Zealand showing a slight increase contrary to regional trends. Eastern Asia had the largest reduction (2&#xb7;8% per year) in all-cause mortality rate and Melanesia (0&#xb7;8% per year) the smallest. Risk factors generally had between-subregion and within-subregion variation; however, some regional trends stood out, with overweight and obesity increasing in all countries across the region, and binge drinking increasing in more countries than not. In 2023, prevalence of smoking in males exceeded that in females in every country, from 40% difference in Timor-Leste to less than 1% difference in Australia. Anaemia prevalence is decreasing in all countries, but female prevalence was higher and reducing at a slower rate than in males. Bullying prevalence was slightly higher in Polynesia, Micronesia, and Melanesia combined, Australia and New Zealand, and eastern Asia compared with southern and south-eastern Asian subregions. INTERPRETATION: Several patterns were consistent across the region: the dominance of mental disorders and NCDs, the universal rise in overweight and obesity (particularly high in Oceanic countries but increasing rapidly in south and south-eastern Asia), and persistent sex-specific challenges across subregions: unintentional injuries and smoking in males, and anaemia in females. Actions to tackle shared risk factors (while accounting for context-specific local health profiles, workforce deficits, cultural factors, and health system capacity) should not be forgone due to local variation. Future research could focus on subnational variation, intersecting inequalities, and multi-sectoral interventions targeting shared risk factors. Priority actions should include regional investment in adolescent mental health services and obesity prevention, targeted injury reduction strategies for high-risk populations, and sex-specific approaches to smoking cessation and anaemia reduction, delivered through local health systems with the capacity and cultural responsiveness to meet local needs. FUNDING: Gates Foundation and Australian Government.

Humans

MicroRNAs in Oral Bio-Fluids as Predictive Biomarkers of Orthodontic Tooth Movement: A Systematic Review.

This systematic review was designed to assess scientific evidence of the association of microRNA expression during orthodontic tooth movement through various time points. A systematic review was performed in accordance with the PRISMA checklist. A search strategy was developed in electronic databases including Med Line, Scopus, EBSCO Host and ProQuest Dissertations & Theses Global until June 2025. Eligibility criteria included studies that investigated microRNA expression in saliva/GCF during orthodontic treatment. The risk of bias of the included studies was analysed using the QUADAS-2 and RoB-2 tools. The search retrieved 2800 records, of which nine studies were selected. Minor variations in GCF collection were noted, while stimulated saliva was collected in one study. RT-PCR and the Fluro meter accounted for the majority of miRNA estimation. Thirteen miRNAs were identified as target biomarkers for OTM regulation. Despite the high risk of bias, the evidence from the current systematic review indicates that microRNAs can be considered as potential biomarkers of orthodontic tooth movement in oral biofluids. Trial Registration: Prospero ID-CRD420251153064.

Humans

SGLF-Net:Staged Global-to-Local Cross-Scale Fusion Network for Colonoscopic Polyp Segmentation.

Polyp segmentation in colonoscopy images plays a pivotal role in computer-aided medical diagnosis and the early prevention of colorectal cancer. However, existing methods often suffer from performance degradation when confronted with extreme polyp scale variation and polyp boundary ambiguity. To address these challenges, we propose the Staged Global-to-Local Cross-Scale Fusion Network (SGLF-Net), which adopts a novel staged global-to-local learning paradigm to progressively refine segmentation from coarse global semantics to fine-grained local details. Specifically, the Global Semantic Perception Stage integrates a Swin Transformer Encoder and a Dynamic Attentive Decoder (DAD) to construct comprehensive multi-scale contextual representations. The Local Detail Refinement Stage employs an Edge-aware Dynamic Attentive Decoder (E-DAD) to enhance structural fidelity and boundary precision through explicit edge-guided supervision. Furthermore, we introduce the Cross Spatial-Scale Feature Aggregation and Reconstitution (CSSAR) module, equipped with hybrid attention mechanisms, to facilitate efficient semantic structural interaction between the two cascaded stages. Extensive experiments on five public benchmark datasets demonstrate that SGLF-Net consistently outperforms state-of-the-art methods in both segmentation accuracy and boundary preservation.

Journal Article

Long-Term Weight Trajectories in Infants Receiving Prolonged Breastfeeding: Impact of Formula Supplementation.

OBJECTIVE: This study compared weight trajectories in infants breastfed for at least 1 year, with or without formula supplementation. STUDY DESIGN: A retrospective cohort of 252 infants followed in well-baby clinics. All infants were breastfed &#x2265;12 months and received complementary foods at 4-6 months. Of these, 174 received no formula, and 78 received daily formula supplementation. Anthropometric data were collected from birth to 5 years of age. RESULTS: Among males, those breastfed without formula had significantly lower body weight between 13 and 18 months compared with those receiving formula (10.20 kg vs. 10.97 kg, p < 0.001). From 19 months onward, no significant weight differences were observed and trajectories converged through 5 years. CONCLUSION: Prolonged breastfeeding in male infants is associated with lower weight in early toddlerhood; however, differences resolve by age two. These findings suggest early variations may represent physiological patterns. Further controlled studies are needed.

Humans

Long-term (>7-year) parental consumption of genetically modified maize (Cry1Ab/Cry2Aj and EPSPS) induces no adverse sperm DNA methylation alterations across two generations of cynomolgus monkeys.

This study assessed the long-term safety of genetically modified (GM) maize from a male reproductive perspective, using a non-human primate model. We analyzed the sperm DNA methylation profiles in cynomolgus monkeys fed GM maize, non-GM parental maize, or a conventional diet over two generations (F0/F1). Whole-genome bisulfite sequencing (WGBS) revealed no significant differences in global methylation levels among groups. The identified differentially methylated regions (DMRs) were short, enriched in non-regulatory genomic areas, and did not cluster after treatment. Functional enrichment analysis showed that DMR-associated genes were consistently involved in the same core biological pathways (e.g., mTOR and Wnt signaling) across all dietary comparisons. These findings indicate that GM maize consumption did not induce specific adverse epigenetic alterations in sperm, with the observed changes reflecting common physiological adaptations to dietary variations rather than GM-related effects.

Animals

Stroke risk following BNT162b2 vaccination: a systematic review and meta-analysis of self-controlled case series studies.

INTRODUCTION: Whether BNT162b2 (Pfizer-BioNTech) vaccination increases stroke risk remains a public health concern. This is the first meta-analysis to synthesize self-controlled case series (SCCS)-derived stroke risk estimates specifically for BNT162b2 vaccination. METHODS: PubMed and Embase were searched from inception through 9 May 2026, following PRISMA 2020 guidelines. Eight eligible SCCS studies were pooled using a random-effects model with restricted maximum likelihood (REML) estimation and the Knapp-Hartung adjustment. RESULTS: Eight studies across six countries encompassing several million vaccinated individuals were included. The pooled incidence rate ratio (IRR) was 0.967 (95% CI 0.892-1.049; I2&#x2009;=&#x2009;69.2%), indicating no statistically significant increase in stroke risk. Subgroup analyses showed no evidence of effect modification across continent, risk-window length, dose category, SCCS variant, or age group. CONCLUSIONS: These findings provide no evidence of increased short-term stroke risk following BNT162b2 vaccination at the population level. The observed heterogeneity appeared to be partly driven by methodological differences rather than true biological variation in vaccine effect.

Humans

Meta-analysis of source identification and apportionment in soil: A systematic review of analytical procedures, receptor modeling, and environmental applications.

Soil pollution poses significant risks to ecosystems and human health, necessitating accurate source identification and apportionment to guide mitigation strategies. This systematic review evaluates the application of Positive Matrix Factorization (PMF) and other receptor models in soil pollution studies, focusing on analytical procedures, tracer indicators, and environmental applications. This review aims to provide a comprehensive framework for conducting soil source apportionment studies, aiding policymakers in designing effective, region-specific environmental management strategies by compiling global trends and methodological insights. The study addresses sampling protocols, emphasizing representativeness and quality control. Data from 500 peer-reviewed publications highlight the dominance of research in China, Eastern Europe, and South Asia, with agricultural soils being the most frequently studied. Key findings reveal that traffic emissions (20.8 %) and industrial activities (19.4 %) are the primary global contributors to soil contamination, with regional variations such as coal combustion in cold climates and agricultural inputs in developing regions. Policy recommendations include stricter industrial regulations, sustainable agricultural practices, and targeted remediation efforts based on source-specific risks.

Soil Pollutants

Peptide molecular lock-engineered nanobodies enable an oriented dual-modal immunoassay for reliable detection of Cronobacter sakazakii.

Conventional nanobody ELISAs for trace Cronobacter sakazakii in powdered infant formula suffer from random orientation and low signal output. We developed an oriented dual-modal immunoassay that combines site-specific biotinylation via a C-terminal AviTag and a peptide molecular lock, enabling controlled surface orientation while preserving nanobody structural integrity. This strategy was further integrated with phage-displayed nanobodies for multivalent amplification and both fluorescent and colorimetric readouts. The assay exhibited a broad linear range of 103-106&#xa0;CFU/mL, with limits of detection (LODs) of 6.70&#xa0;&#xd7;&#xa0;102&#xa0;CFU/mL for fluorescence and 1.55&#xa0;&#xd7;&#xa0;103&#xa0;CFU/mL for colorimetry, showing improved sensitivity compared with the conventional passive adsorption-based Nb-ELISA evaluated in this study. XGBoost-based multimodal fusion improved quantitative accuracy, and SHAP analysis elucidated modality contributions. In spiked powdered infant formula samples, recoveries ranged from 92.1% to 118% with coefficients of variation below 5.98%, confirming acceptable matrix tolerance and analytical reliability.

Cronobacter sakazakii

A chromosome-level, haplotype-resolved genome assembly for the barn owl, Tyto alba.

Recent advances in long-read sequencing have enabled near telomere-to-telomere (T2T) assemblies across diverse taxa. However, avian genomes remain challenging due to numerous microchromosomes, small, typically < 20Mb, DNA molecules that are gene-, GC-, and repeat-rich. As a consequence, microchromosomes are often missing from genome assemblies. Here, we present a chromosome-level, haplotype-resolved genome assembly for the Western barn owl (Tyto alba). Using a trio-binning strategy with Illumina parental reads combined with PacBio HiFi and Oxford Nanopore Technologies data, we generated two phased contig sets. These were scaffolded into 40 linkage groups using a linkage map. Comparative analyses identified unplaced HiFi scaffolds corresponding to microchromosomes, which we integrated into six additional microchromosomes using long reads information. The two assemblies present 46 chromosomes, matching the karyotype of the species. They exhibit strong synteny between parental haplotypes, except for a &#x223c;38 Mb complex region on chromosome 7 containing nested inversions. This high-quality reference provides a haplotype-resolved and chromosome-level genome for Strigiformes, enabling fine-scale studies of structural variation and avian genome evolution.

Tyto alba

A Systematic Review of Lived Experiences of Receiving a Diagnosis of ADHD in Adulthood.

OBJECTIVE: With rising numbers of adults seeking and receiving ADHD diagnoses, understanding their first-hand experiences of the diagnostic process is key for sensitive support and service design. This systematic review collates, evaluates and synthesises the existing evidence-base on lived experiences of adult ADHD diagnosis. METHOD: Keyword searches of six databases generated 10,357 citations, which were subjected to a systematic screening process that identified 21 relevant studies. Findings were analysed using thematic synthesis. RESULTS: Analysis generated three overarching themes, elaborating how diagnostic experiences are shaped by adults' Relationship with Self, Relationship with Others, and Relationship with Systems. Personally, diagnosis was widely experienced as a pivotal identity event, triggering biographical reflection that could foster greater self-compassion, but also grief, anger and identity confusion. Socially, diagnosis facilitated interpersonal understanding and communication, but also exposed adults to stigma and introduced dilemmas about diagnostic disclosure. Systemically, adults experienced the diagnostic process as beset by barriers and delays, and reported highly variable access to post-diagnosis supports or treatment. CONCLUSION: Results suggest receiving an ADHD diagnosis in adulthood is a complex relational process that can be both validating and destabilising, with variation in experiences resulting from individual biographies, interpersonal resources, stigma climates, and service structures.

Humans

Evolutionary architecture and lineage-specific diversification of Forkhead box transcription factors in Perna viridis.

The Forkhead box (Fox) transcription factors are evolutionarily conserved regulators of development, cell cycle, and apoptosis across metazoans. This study provides the first comprehensive genome-wide analysis of the Fox gene family in the Asian green mussel (Perna viridis). We identified 28 Fox genes distributed across 10 chromosomes. Comparative analysis reveals the absence of the FoxI, FoxQ1, FoxR and FoxS subfamily, consistent with other bivalves and indicative of lineage-specific gene loss during molluscan evolution. Notably, gene duplications in the FoxAB, FoxD, FoxH, FoxN1-4, FoxQ2 and FoxQD subfamilies may reflect functional diversification associated with environmental adaptation. Exon-intron structural variability, including intron loss in several paralogues, suggests structural diversification and potential regulatory variation. Phylogenetic reconstruction confirmed the monophyly of core Fox classes while highlighting divergent expansion patterns in lophotrochozoans. Selection analyses showed strong purifying selection across duplicated Fox paralogs, supporting functional conservation after lineage-specific expansion. Gene Ontology enrichment linked Fox genes to stress response, apoptosis, and transcriptional regulation. By integrating phylogenetic, structural, and transcriptomic analyses, this study provides a genomic framework for understanding Fox gene organisation, evolution, and tissue-associated expression patterns in Perna viridis and establishes a comparative resource for future functional studies in bivalves.

Animals

Genetic diversity and recombination of&#xa0;NA-PRRSV field strains in Vietnam: Implications for vaccine efficacy.

Porcine reproductive and respiratory syndrome (PRRS) causes severe reproductive losses in pregnant sows and piglets, resulting in substantial economic impact on the swine industry worldwide. However, due to the significant genetic diversity and rapid evolutionary changes of the pathogen, continuous surveillance and detailed genetic analysis of circulating strains are essential. The current study aimed to evaluate the genetic diversity of the hypervariable (HV) region of non-structural protein 2 (nsp2) among North American PRRSV strains isolated from swine farms in Vietnam. Phylogenetic analysis and multiple sequence alignment were conducted to determine subtype classification and assess genetic variability. A total of 48 field isolates were obtained, of which 12.5% belonged to classical NA-PRRSV, 16.6% to NADC30-like and 70.9% to HP-PRRSV, primarily distributed across sublineages 1.4, 5.1, 8.7 and 8.9. Amino acid comparisons found multiple insertions, deletions and substitutions at various positions within the hypervariable region of nsp2. The study revealed substantial genetic variation in the HV region of nsp2 among NA-PRRSV field strains, largely associated with recombination and immune escape. These findings highlight epidemiological risks to vaccine efficacy and underscore the need for continuous molecular surveillance to support effective PRRSV control in Vietnam.

PRRSV

Determinants of Meal Satisfaction and Their Association With Childhood Obesity: A Systematic Review.

Meal satisfaction is considered a multidimensional concept that includes sensory enjoyment, cognitive, emotional, and physiological components and relates to contentment with the meal experience as a whole. However, its relevance to eating behavior and body weight remains unclear, especially in children. The present review investigated the potential relationship between meal satisfaction-related constructs and childhood obesity, and whether this relation is shaped by individual factors and the external environment. Seventeen eligible studies from 350 records published between 2008 and 2024 were included. No study directly assessed meal satisfaction; instead, proxy measures were used. Food enjoyment emerged as the proxy most consistently associated with BMI, often clustering with higher food responsiveness, lower satiety responsiveness, and emotional overeating. Parental feeding practices, especially pressure to eat, significantly contributed to variation in children's eating behavior and were associated with lower food enjoyment. Overall, meal satisfaction could be a key aspect to consider in childhood obesity prevention programs. However, to date, the available evidence is heterogeneous and predominantly observational. Future longitudinal and intervention studies are needed, alongside child-appropriate instruments to objectively quantify food satisfaction in children. Research that helps understand the role of contextual eating factors on children's meal satisfaction and eating behavior is also warranted.

Humans

Simultaneous Administration of Human Papillomavirus (HPV) Vaccine With Other Recommended Vaccines Among Adolescents Aged 13-17 years, National Immunization Survey-Teen (NIS-Teen), United States, 2023.

PURPOSE: To investigate the percent of adolescents who receive human papillomavirus (HPV) vaccine with one or more other vaccines recommended for adolescents in a single medical visit. METHODS: Data from the 2023 National Immunization Survey-Teen were analyzed. Timing of receipt of HPV vaccine, tetanus, diphtheria, and acellular pertussis vaccine (Tdap), quadrivalent meningococcal conjugate vaccine (MenACWY), and influenza vaccine was assessed using provider-reported vaccination histories. RESULTS: In 2023, among adolescents aged 13-17 years, 69.5% received HPV vaccine with one or more other vaccines recommended for adolescents in a single medical visit. In addition, 47.8% received specifically HPV vaccine, Tdap, and MenACWY together in a single medical visit. DISCUSSION: The HPV vaccine is commonly given with other vaccines recommended for adolescents in a single medical visit. These findings demonstrate variation in simultaneous vaccination patterns, suggesting that flexibility in the recommended adolescent vaccination schedule allows for different approaches to vaccination across clinical settings and family preferences while maintaining adherence to the recommended schedule.

Humans

Parent-of-origin effects on allelic expression bias in interspecific poplar hybrids.

In hybrid plants, phenotypic outcomes are governed by interactions between the two parental genomes. However, the mechanisms underlying the interplay of divergent regulatory networks from these genomes remain poorly understood. In this study, we compared gene-level and allele-specific expression patterns, as well as differentially enriched pathways between F&#x2081; and complex backcross (CBC) lines derived from a natural interspecific hybrid population of Populus fremontii (Pf) and P. angustifolia (Pa). Metabolic differences between Pf and Pa which exhibit low and high levels respectively of phenylpropanoid-derived condensed tannins were leveraged. Using individualized transcriptome references, differential expression and clustering analyses revealed CBC-biased and F&#x2081;-biased expression for genes involved in phenylpropanoid metabolism and photosynthesis, respectively. Biased expression of these genes at the allele level was also observed in F1. At the whole-transcriptome level, Pa-biased genes predominated in F&#x2081; hybrids, and Pa alleles displayed more conserved expression patterns than Pf alleles across examined samples. Further analyses indicated that allelic expression bias was significantly associated with parental origin, which could be driven by sequence variations in cis-regulatory elements and differences in CpG island length. Our findings demonstrate strong parent-of-origin effects on divergent regulatory networks governing gene expression in poplar hybrids and provide clues for strategic parental selection tailored to specific metabolic pathways of interest.

cis-regulation

Domestication-associated reduction of methyl salicylate in tomato root and its significance for resistance to root-knot nematode.

Methyl salicylate (MeSA) plays diverse roles in the aerial parts of plants. By contrast, its biosynthesis and function in roots remain poorly understood. Here, we investigated root MeSA biosynthesis and function in tomato. Genome-wide association studies (GWAS) were performed using root MeSA levels as the phenotype in a diversity panel of 167 accessions to identify associated loci. Candidate genes were biochemically characterized, and the role of MeSA in defense against root-knot nematode (RKN, Meloidogyne incognita) was evaluated using transgenic plants. MeSA was identified as a major root volatile in tomato and showed a domestication-associated reduction. GWAS revealed multiple loci associated with natural variation in root MeSA, including a major locus on Chromosome 9 encoding the salicylic acid methyltransferase (SlSAMT). SlSAMT-overexpressing plants showed reduced resistance to RKNs, whereas SlSAMT-knockdown plants exhibited enhanced resistance. Our results suggest complex roles of MeSA and the salicylic acid (SA) signaling pathway in belowground plant defense. The SA signaling pathway likely plays critical roles in protecting roots against diverse natural enemies, including RKNs. Nevertheless, RKNs appear to have co-opted MeSA as a host-location signal, and the domestication-associated reduction of root MeSA in tomato has likely contributed to enhanced resistance against RKNs.

Solanum lycopersicum