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At least 19 recordsLinked to original sources
PubMed1979

Diabetes: the genetic connections.

Insulin dependent (IDD) and non-insulin dependent diabetes (NIDD) are separate disorders. Twin studies show that IDD cannot be entirely due to genetic causes as concordance is no more than about 50%, but there is some inherited predisposition to it as shown by HLA patterns. NIDD, on the other hand, is predominantly due to genetic causes since identical twins are nearly always concordant. Many cases of NIDD show chlorpropamide alcohol flushing (CPAF), a dominantly inherited feature which may precede the appearance of diabetes and thus act as a genetic marker for this type of diabetes. Diabetics who show chlorpropamide acohol flushing are less likely to develop retinopathy than those who do not. Genetic factors must therefore affect the incidence and severity of diabetic retinopathy. Chlorpropamide alcohol flushing is due to sensitivity to enkephalin. Enkephalin and other opioids affect carbohydrate metabolism and insulin release. It is possible therefore that they act as neurotransmitters and cause NIDD by a sympathetically mediated effect on the liver and pancreas--in other words, that as far as NIDD is concerned Claude Bernard's views on the cause of diabetes may have been right.

Chlorpropamide↗
PubMed2026

Panmixia in a Widespread Butterfly: High Dispersal and Ecological Generalism Buffer Against Landscape Fragmentation.

Habitat fragmentation is widely expected to reduce population connectivity and increase genetic differentiation, although the strength of these effects depends on species-specific traits such as dispersal ability. Here, we investigated the population genetic structure of the cosmopolitan butterfly, Pieris rapae L. (Lepidoptera: Pieridae), across western Germany using genome-wide single-nucleotide polymorphism (SNP) data. To analyze the effects of landscape structure on genetic connectivity, we applied a paired study design comprising four landscape pairs, each consisting of a highly intensified, modern agricultural landscape and a more heterogeneous, traditional landscape. Our results revealed no evidence of genetic differentiation. Pairwise FST values were close to zero; we detected no isolation by distance, and clustering analyses supported a single genetic population. No meaningful associations between genetic variation and environmental variables were detected, with landscape effects explaining less than 0.4% of genomic variation. Consequently, we found no evidence for stronger genetic structuring in modern compared to more connected traditional landscapes. Our results suggest that extensive habitat fragmentation does not necessarily translate into reduced genetic connectivity in highly mobile, generalist species. In P. rapae , high dispersal ability and ecological generalism appear to buffer against the genetic consequences of landscape modification, resulting in panmictic population structure even across strongly contrasting agricultural landscapes.

Pieris rapae↗
PubMed2026

Shared genetic architecture of obesity and gastroesophageal reflux disease.

Obesity is identified as a risk factor of gastroesophageal reflux disease (GERD). This study aims to elucidate the shared genetic architecture of obesity-related phenotypes and GERD. Based on the publicly available genome-wide association studies' datasets, this genome-wide pleiotropic association study was conducted with various genetic approaches (including linkage disequilibrium score regression, high-definition likelihood inference for genetic correlations, pleiotropic analysis under composite null hypothesis, Functional Mapping and Annotation, Bayesian colocalization, summary-based Mendelian randomization, and multi-marker analysis of genomic annotation analysis) sequentially to unravel the genetic associations from single-nucleotide polymorphism to gene levels, and to reveal the underlying shared genetic architecture between obesity-related phenotypes and GERD. This study discovered shared genetic mechanisms between GERD and several obesity-related phenotypes, including arm fat percentage (left), arm fat percentage (right), leg fat percentage (left), leg fat percentage (right), trunk fat percentage, waist-to-hip ratio, and body mass index. Significant genetic correlations were observed by linkage disequilibrium score regression and high-definition likelihood inference for genetic correlations, with multiple associated pleiotropic loci and their mapped genes identified by pleiotropic analysis under composite null hypothesis, Functional Mapping and Annotation, Bayesian colocalization, summary-based Mendelian randomization, and multi-marker analysis of genomic annotation analysis. Additionally, several brain tissues were identified to be linked to both obesity and GERD by multi-marker analysis of genomic annotation. This research provided strong evidence of genetic correlations and brought novel insights into the underlying genetic connections and shared genetic architectures of obesity and GERD.

Humans↗
PubMed2026

Diversity and population connectivity of members of the family Eunicidae inhabiting deep-water corals in the North Atlantic.

Eunicid polychaetes are often found in association with Cold Water Corals (CWCs), even establishing symbiotic relationships, such as those described between Desmophyllum pertusum and Eunice norvegica. While genetic connectivity of CWCs across the North Atlantic has been widely studied, little is known about their associated fauna in this regard. Here, we present a study combining a focused analysis of the genetic and genomic connectivity of E. norvegica with a regional assessment of the distribution and evolutionary relationships of three CWC-associated eunicid species from the Cantabrian Sea and the North of the United Kingdom (190-1,230 m depth). An integrative approach using genetic (16S, COI and 18S), morphological and ecological data allowed the identification of the eunicids studied, with new records of Eunice cf. nicidioformis and Leodice cf. antarctica in the Cantabrian Sea, as well as previously undocumented associations with CWC species. In addition, RADseq data contributed to the delimitation of the closely related species E. norvegica and Eunice philocorallia. Moreover, the genetic connectivity of E. norvegica was studied trough a RADseq (1,067 neutral SNPs) approach. Our results indicate a single panmictic population across approximately 2,000 km, suggesting that oceanographic currents facilitate passive dispersal of E. norvegica lecithotrophic larvae, aided by coral host stepping-stones. The connectivity patterns observed for E. norvegica mirror those of D. pertusum, on which the worm is ecologically dependent. Our study highlights the importance of using integrated genetic, morphological and ecological data to characterise and delineate understudied CWC-associated species and improve our understanding of their dispersal capabilities and genetic connectivity to inform future conservation recommendations.

Animals↗
PubMed2026

Fine-Scale Landscape Genomics Show Asymmetric Patterns of Gene Flow for the Invasive Mosquito Aedes albopictus.

Mosquito-borne viruses like dengue, Zika, and chikungunya pose increasing health risks in the United States due to the expanding range of Aedes albopictus, a highly invasive mosquito species that now has a global distribution. Aedes albopictus thrive in artificial containers associated with anthropogenic land use, allowing populations to reach high numbers in urban and suburban environments. While the global spread of Ae. albopictus has been well characterized, the effects of heterogeneous urban landscapes on dispersal and gene flow at fine spatial scales remain unclear. This study analyzed the genetic connectivity of Aedes albopictus populations collected in Wake County, North Carolina in 2018. We used single nucleotide polymorphisms (SNP) data from double-digest restriction-enzyme associated DNA sequencing (ddRADseq) and examined genetic connectivity through principal component analysis (PCA) and genetic network analysis. We then evaluated migration and source-sink dynamics using a Bayesian approach for SNP data (BA3-SNP). We found little evidence of genetic clustering or isolated populations of Ae. albopictus in Wake County, suggesting high gene flow between sites. Migration analysis demonstrated asymmetric gene flow from rural to urban regions within Wake County, with greater gene flow occurring between and within urban regions. These findings suggest that the pattern of gene flow of Ae. albopictus populations within local metropolitan areas may involve urban city centers serving as genetic sinks and surrounding suburban and rural regions serving as sources. This study highlights how heterogeneous landscapes shape mosquito population connectivity and migration at fine spatial scales, which is critical for informing vector control and public health intervention strategies.

Aedes albopictus↗
PubMed2026

High connectivity and genetic diversity in the Endangered endemic white-spotted sand bass 'camotillo' (Paralabrax albomaculatus) within the Galápagos Marine Reserve.

BACKGROUND: Paralabrax albomaculatus, known as the camotillo or white-spotted sand bass, is a finfish endemic to the Galápagos Islands. An important species in the artisanal fishery, P. albomaculatus has undergone heavy population declines in recent decades, and is categorised as Endangered by the IUCN. Despite its socio-economic importance and endemic status, nothing is currently known about the population structure of the species, impeding evidence-based fisheries management. In this study, we use microsatellite markers to investigate its population structure and genetic diversity over the east, south and west of the Galápagos archipelago. RESULTS: We found evidence of high connectivity across the archipelago, with the species constituting a single population. We also found that genetic diversity was high, despite fishing pressure and recorded ongoing population declines. CONCLUSIONS: Our results suggest that P. albomaculatus should be managed as a single fishery stock across the Galápagos. As a single-population species and fishery, managers should also be aware that P. albomaculatus is inherently vulnerable to perturbation as recruitment from other populations is not possible in the event of population decline. However, high genetic diversity gives cause for cautious optimism regarding the genetic capacity for resilience of the population to novel environmental stressors. These results should aid in the implementation of a species-specific management plan for this Galápagos endemic.

Animals↗
PubMed1977

Primary and secondary disturbances in trace element metabolism connected with genetic metabolic disorders.

Several primarily inherited disturbances of minerals and trace elements have been discovered within the last 20 years. Secondary disturbances of selenium and zinc induced by dietetic treatment of inborn errors of metabolism and by parenteral nutrition also came to our knowledge recently. Two main types of chronic or primary hypomagnesaemia are known which are caused either by impaired intestinal absorption or by false magnesium handling by the kidneys. In acrodermatitis enteropathica, an autosomal-recessive inherited disease leading to characteristic skin lesions, alopecia and dystrophy, low zinc concentrations of serum, urine and hair are measured. The intestinal absorption of zinc is reduced. In copper metabolism two inherited diseases are known with low serum and usually caerulosplasmin concentrations. In Menkes' steely hair syndrome (trichlpoliodystrophy) an intestinal net malabsorption of copper exists, whereas in Wilson's disease the copper contents of several organs are increased.

Adult↗
PubMed2026

Larval Genomics as a Viable, Fisheries-Independent Tool for Investigating Population Structure in Tropical Pacific Tunas.

Understanding how dispersal, life history, and environmental variability shape genetic connectivity in the open ocean remains a central challenge in evolutionary biology. Highly migratory marine predators like tunas have traditionally been considered genetically homogeneous across ocean basins, yet emerging genomic evidence suggests that cryptic population structure can persist even in species with high gene flow and large effective population sizes. We used 2bRAD sequencing of 348 larval and subadult skipjack (Katsuwonus pelamis), yellowfin (Thunnus albacares), and bigeye tuna (T. obesus) collected from the central Pacific across 7 years of sampling to examine species boundaries, population genetic information, genetic structure, and connectivity. Larval sampling revealed consistent spawning by all three species and enabled unbiased detection of genetic patterns prior to recruitment bottlenecks. We found strong divergence amongst species, no evidence of structuring within skipjack or bigeye, and a divergent yellowfin population detected in 2 consecutive sampling years north of American Samoa. Comparisons between larvae and subadults suggest that sampling early life history stages can be a valuable tool for assessing population genetic information before recruitment bottlenecks, selective harvest by fisheries, adult dispersal, and selective pressures acting on adult populations, thereby contributing novel insights to the research and effective management of these species. These results highlight how larval genomics can complement traditional population genomic studies of adult tunas and reveal fine-scale structure in highly vagile species, providing new perspectives on connectivity in the open ocean.

Animals↗
PubMed2025

What Should a Clinical Cardiologist Know About Cardiogenetics?

Inherited cardiovascular diseases are becoming increasingly prominent in clinical practice, significantly impacting diagnosis, risk assessment, and family screening strategies. Progress in genetic testing has broadened access to cardiogenetic evaluations, while also presenting new challenges in interpreting variants and incorporating findings into clinical care. This narrative review explores 20 essential questions that clinical cardiologists may face when dealing with suspected or confirmed inherited cardiac conditions. Organized as a practical, question-driven guide, it outlines when to consider a genetic cause, how to choose and interpret genetic tests, and how to manage patients regardless of their genetic test results. The review emphasizes variant classification based on American College of Medical Genetics and Genomics criteria, the importance of clinical context in interpreting uncertain results, and the principles behind family cascade screening. Particular attention is given to the management of relatives who carry a genetic variant but show no symptoms, and to the current limitations of genetic testing technologies (eg, performance). Ethical considerations, including the appropriate timing of testing in children minors, are also discussed. By connecting genetic insights with clinical cardiology, this review aims to support practical, informed decision making and promote effective collaboration with cardiogenetic specialists.

Humans↗
PubMed2026

Assessment of Genetic Diversity and Population Structure on Azadirachta indica A. Juss. in an Urban Metropolitan: Ahmedabad, India.

Azadirachta indica (A. indica) A. Juss., commonly known as Neem, is a valuable multipurpose tree with profound medicinal properties and socioeconomic importance, widely recognized since ancient Ayurvedic times. Despite its prominence, knowledge about its genetic diversity within the metropolitan area of Ahmedabad is limited. This study marks the first in-depth exploration of the genetic diversity and population structure of A. indica in Ahmedabad. The authenticity of the species was validated through DNA barcoding, and a Geographical Information System (GIS) was used to collect the samples. A total of 35 A. indica accessions were analyzed using five Inter Simple Sequence Repeat (ISSR) primers. Genetic diversity and population structure were evaluated using Inter Simple Sequence Repeat (ISSR) markers through polymorphism assessment, clustering, ordination, and Bayesian population structure analyses. ISSRs revealed a high level of polymorphism (75.66%), indicating substantial genetic variability among accessions. An analysis of genetic diversity indices revealed low to moderate diversity (Hs = 0.14, Ht = 0.217, I = 0.217). Analysis of Molecular Variance (AMOVA) analysis depicted 81% variation within the population and 19% among the population. Low to moderate genetic differentiation (Gst = 0.319) and moderate gene flow (Nm = 1.06) indicated that urban development has not hindered gene flow among populations. Mantel's test revealed a weak but significant correlation between genetic and geographic distances, suggesting limited isolation by distance. The estimated ΔK using STRUCTURE exhibited two subpopulations, representing two gene pools for A. indica accessions (K = 2). Collectively, these patterns indicate that urbanization has not severely disrupted genetic connectivity in A. indica, reflecting its resilience and adaptive potential in a metropolitan environment. These findings provide pivotal knowledge for further understanding the genetic diversity and population structure of A. indica in one of the fastest-growing cities in India, which can be utilized for new breeding programmes, sustainable development and future conservation strategies around the globe.

India↗
PubMed2026

Dissecting pleiotropy between major depressive disorder and physical disease comorbidities.

Major depressive disorder (MDD) is characterized by substantial comorbidity with medical conditions. To achieve better outcomes for patients with MDD, an improved understanding of the mechanisms underlying pervasive comorbidities is required. Here, to this end, we mapped patterns of pleiotropy by defining four clusters of physical diseases (cardiovascular, metabolic, gastrointestinal and immune) and analyzed their genetic relationships with MDD using genomic structural equation modeling. Three disease clusters exhibited independent associations with MDD and accounted for 47% of MDD h2SNP, with the gastrointestinal disease cluster having the strongest association (β = 0.63, s.e. = 0.05, P = 3.04 × 10-30). In addition, we identified independent loci associated with the shared genetic liability between each disease cluster and MDD, revealing different pleiotropic components. Characterization of these loci revealed previously unidentified associations with MDD and physical disease traits, along with unique biological pathways, drug groups, cell types and genes associated with each disease-MDD cluster. Our findings reveal genetic connections implicating the gut-brain axis as a key mechanism underlying the comorbidity of physical diseases in MDD. This work advances our understanding of MDD by highlighting unique and shared genetic components across different disease systems.

Major Depressive Disorder↗
PubMed1976

[A short observation on the cause of myopia (author's transl)].

The increased excretion of acid mucopolysaccharides in the urine of patients with advanced myopia is indeed relevant for understanding the chemical processes in the sclera during this period, but it does not say anything concerning the genesis of myopia as such. This is due more to an infiltrative malformation of the eyeball and the optic nerve. The behaviour of the connective tissue can also be due to infiltration, or contrariwise induced from parenchyma at the appropriate time. Hence therapeutic possibilities can hardly be deduced from the chemistry of the sclera. Abnormally small corneas in people with high myopia point to a genetic connection between such eyes and "true" microphthalmos with orbital cyst.

Humans↗
PubMed2026

Characterizing the impact of plasma protein levels on human brain structure and disorders leveraging integrative multi-omics analysis.

With recent advances in high-throughput proteomic technologies, population-scale plasma proteomics datasets, often linked to extensive genetic and phenotypic information, have become increasingly accessible. Yet the relationships between circulating protein levels, brain imaging phenotypes, and risk for neurological and psychiatric disorders remain largely unexplored. Proteome-wide association studies offer a promising approach for elucidating biological mechanisms that connect genetic variation to complex brain-related traits and diseases. In this study, we integrated protein quantitative trait loci (pQTLs) from the two largest plasma proteomic resources (the UK Biobank Pharma Proteomics Project [UKB-PPP] and Ferkingstad et al. [deCODE]) with genome-wide association studies of brain imaging-derived phenotypes in UK Biobank using Mendelian randomization and colocalization analyses. We identified 120 cis and 20 trans associations between plasma proteins and imaging phenotypes and validated these findings using brain tissue-derived proteomic and transcriptomic datasets. Multivariable Mendelian randomization revealed eleven plasma proteins (coding genes APOE, ARL3, MICB, NSF, RHOC, RSPO3, ENPP2, BTN2A1, EIF2AK3, MRVI1, and OPLAH) with significant direct effects on the risk of Alzheimer's disease, Parkinson's disease, multiple sclerosis, bipolar disorder, and schizophrenia. Single-cell expression and pathway enrichment analyses further revealed cell-type-specific effects and distinct biological processes underlying these protein-disease associations. Together, these findings demonstrate robust links between plasma protein variation and brain structure, delineate protein-disease pathways, and highlight the cellular and molecular mechanisms that contribute to neurobiological diversity and pathology.

Journal Article↗
PubMed2026

From genotype to phenotype: understanding the genetic basis of autism.

PURPOSE OF REVIEW: This paper covers some of the key findings on the topic of genetic influences in autism over the last 12-18 months, which consist of significant conceptual shifts and new insights from recent technological advances. RECENT FINDINGS: Autism is a highly heritable condition, with significant heterogeneity of the genes that influence the development of this condition. The heterogeneity of autism, and multiple pathways contributing to the development of an autistic phenotype, create challenges in our understanding, diagnosis, and management of this condition.Recent studies of common genetic variation and polygenic risk scores have focussed on resolving phenotypic heterogeneity and identifying meaningful autism subtypes. Rare-variant discovery has expanded across ancestries, the X chromosome, noncoding loci, structural variants, and tandem repeats, aided by long-read and pangenome-informed sequencing. Single-cell multiomics, spatial perturbation methods and human organoid models have connected genetic variation to cell-type-specific and developmental phenotypes, while also revealing substantial mutation-specific effects and methodological sensitivity. Genetic testing increasingly provides aetiological diagnoses and informs medical surveillance. Recent developments also illustrate the therapeutic potential of gene-first approaches for selected monogenic neurodevelopmental disorders. SUMMARY: Recent developments have expanded our understanding of the way the genetic basis of autism manifests phenotypically.

autism↗
PubMed2026

Multilevel Exploration of Shared Genetic Architecture Between Primary Biliary Cholangitis and Four Autoimmune Diseases.

INTRODUCTION: Primary Biliary Cholangitis (PBC) frequently coexists with various autoimmune diseases, such as Multiple Sclerosis (MS), Psoriasis (PS), Rheumatoid Arthritis (RA), and Sjögren's Syndrome (SS). Understanding the genetic associations between these diseases is crucial for providing deeper insights into their shared pathogenic mechanisms and comorbidity patterns. METHODS: This study utilized genome-wide association study summary data of PBC and four autoimmune diseases (MS, PS, RA, and SS). A multi-stage analytical pipeline was employed to systematically investigate the genetic associations between the diseases. The analytical approach consisted of three stages: first, linkage disequilibrium score regression and high-definition likelihood methods were applied to estimate overall genetic correlations between the diseases; second, local genetic correlation analysis was conducted to pinpoint genetic signals in specific chromosomal regions; third, conditional/conjunctional false discovery rate (cond/conjFDR) algorithms were used to quantitatively assess genetic overlap and identify shared susceptibility loci. RESULTS: Genome-wide analysis revealed significant genetic associations between PBC and the four autoimmune diseases (MS, PS, RA, and SS). Regional analysis showed local genetic correlations across various chromosomal segments. cond/conjFDR analysis confirmed genetic intersections among the diseases and identified several critical genetic polymorphic loci that influence disease susceptibility. DISCUSSION: This study comprehensively delineates the shared genetic architecture underlying PBC and four autoimmune diseases through integrative analyses of multiple genome-wide approaches. The results highlight strong genetic correlations, particularly between PBC and MS, PS, RA, and SS, and identify key shared susceptibility genes, including CLEC16A, CD58, CD86, STAT4, IRF5, TYK2, and TNFAIP3, which collectively mediate immune dysregulation through autophagy, cytokine signaling, and NF-κB pathways. These findings not only extend current understanding of the molecular mechanisms driving autoimmune comorbidity but also provide potential genetic targets for future functional validation and therapeutic exploration. CONCLUSION: This study provides comprehensive genomic evidence for the genetic connections between PBC and the four autoimmune diseases (MS, PS, RA, and SS), offering valuable insights into the shared pathological mechanisms underlying their comorbidities.

Humans↗
PubMed2026

Emergence and phylogeography of the dengue vector Aedes aegypti in Southeastern Iran.

BACKGROUND: Aedes (Stegomyia) aegypti (Linnaeus) is the primary vector of dengue, chikungunya, Zika, and yellow fever viruses. Its recent detection in southeastern Iran raises public health concerns about arbovirus spread to new regions. This study provides the first genetic and phylogeographic analysis of Ae. aegypti populations from Sistan and Baluchistan Province (SBP), Iran, to infer their origin and invasion pathways. METHODS: Mitochondrial COI and ND4 genes were analysed in newly collected Ae. aegypti specimens from border areas, ports, and urban centres of SBP. Haplotype network analyses were constructed using the TCS method in PopART, and phylogenetic analyses were conducted using global reference sequences. RESULTS: Iranian specimens comprised 7 COI haplotypes (n = 18) and 10 ND4 haplotypes (n = 17). COI phylogeny placed Iranian specimens into two main clades, while ND4 analysis distributed them across several derived clades, mostly clustering with lineages from Latin America (Brazil, Mexico) or Africa. One Iranian specimen showed a close relationship with a Saudi Arabian sequence (bootstrap: 98%) near the basal region. Combined COI + ND4 analysis revealed a monophyletic clade of Iranian specimens with a Sri Lankan specimen, distinct from other global lineages. The global COI network (n = 47) showed a star-like topology with a dominant haplotype 1 shared among 10 Iranian specimens. The ND4 network (n = 31) revealed a complex topology with 18 haplotypes, where a Saudi Arabian and one Iranian specimen (~30 mutational steps) possibly represented the peripheral root. CONCLUSIONS: Detection of diverse Ae. aegypti clades confirm establishment of this vector in southeastern Iran. Results support multiple introductions and genetic connectivity with Latin America, Africa, and South Asia, pointing to an emerging invasion corridor. Continued genomic surveillance and integrated vector monitoring are urgently needed to guide prevention strategies.

Animals↗
PubMed1977

[Biological activity of extracts isolated from a virulent strain of Sh. flexneri grown in the presence of calcium ions].

The authors carried out a comparative study of the genetically connected Sh. flexneri cultures (3 virulent strains, 3 clones of an avirulent mutant selected in the flux of an oblique light from the virulent strain, and lac+ Kcp A-hybrids obtained by crossing the initial virulent cultures with the E. coli K12 Hfr strains). The absence of any correlation between the virulence of the strains under study and the lipopolysaccharide (by rhamnose) content in the extracts from them in growing the cultures in the presence of calcium ions was noted. Toxicity of the extracts from the virulent cultures was demonstrated on a model of developing chick embryos. No such property was possessed by the extracts from avirulent strains. The extracts from the virulent cultures in nontoxic doses possessed the capacity to decrease LD50 of shigella strains used for the infection. The biologically active factor determined in the extracts from the virulent cultures apparently was not lipopolysaccharide.

Animals↗