Stiphodon is a genus of gobioid fishes found primarily in freshwater streams on islands throughout the Indo-Pacific region. It is the most speciose genus of Sicydiinae, with more than three dozen named species. Complete mitochondrial genome (mtDNA) sequences were determined for three species, namely Stapledon atropurpureus, Stapledon elegans, and Stapledon semoni. Maximum likelihood and Bayes inference inferences from 13 protein-coding genes (11,433 bp) or the COXI gene (1,551 bp) alone were made on these three together with four mitogenomes previously available. S. percnopterygionus and S. tuivi formed an outgroup to the other five Stiphodon species, meanwhile Stapledon atropurpureus and S. semoni were recovered as sister species. The ratios of the non-synonymous to the synonymous substitution rates for all PCGs were in the range 0 < (Ka/Ks) < 1, which suggests they have been subject to purifying selection.
Nonalcoholic fatty liver disease (NAFLD) is a complex condition influenced by metabolic and genetic factors, yet the shared genetic architecture underlying its progression remains poorly understood. The aim of this study was to employ genomic structural equation modeling (GSEM) to elucidate the genetic architecture linking NAFLD with key metabolic traits-including insulin resistance, body mass index (BMI), hemoglobin A1c (HbA1c), and liver fibrosis using summary statistics from large-scale genome-wide association studies. By harmonizing 2.18 million variants across five genome-wide association studies (GWAS) datasets, we identified 134 genome-wide significant loci that mapped to 24 genes. GSEM revealed a latent genetic structure composed of two distinct dimensions: a metabolic regulation factor primarily driven by insulin resistance, BMI, and HbA1c; and a structural pathology factor specifically associated with liver fibrosis. These factors explained 65.5% and 78.1% of the genetic variance in BMI and fibrosis, respectively, with minimal correlation (rg = 0:07), indicating their genetic distinctness. Additionally, integrating Mendelian randomization with liver transcriptome profiling, we characterized how the 24 genes contribute to disease and identified mitochondrial glycerol-3-phosphate acyltransferase (GPAM) as the key gene that causally links lipid metabolism to fibrogenesis. In conclusion, we present the first genetically grounded mechanism for the progression of NAFLD to fibrosis. This mechanism encompasssses genetic variants, dysregulated gene expression, metabolic disturbances, and the processes involved in fibrotic remodeling. This research establishes a genetic framework for understanding the pathogenesis of NAFLD and highlights novel therapeutic targets for intervention.
The EDAR gene is a classic target of positive selection in humans, mainly through the nonsynonymous variant rs3827760 (EDARV370A) associated with ectodermal traits. Using high-resolution data from the 1000 Genomes Project, we combined sliding-window F_ST, BayeScan, and extended haplotype homozygosity (EHH) analyses to examine global and Latin American patterns of differentiation. Globally, a strong signal of positive selection was confirmed at EDAR, dominated by the rs3827760 haplotype background and its extended linkage disequilibrium structure. In contrast, within Latin America, differentiation reflected admixture-driven haplotype persistence rather than contemporary selection. A genome-wide FST scan comparing individuals from the upper and lower quartiles of Native American ancestry showed that EDAR lies among the most highly differentiated regions in this contrast, consistent with ancestry-driven haplotype structure rather than post-admixture adaptive evolution. These results indicate that EDAR retains its evolutionary signature globally but not within recently admixed populations, where demographic history rather than selection shapes its genetic landscape.
This article has been retracted by the Editor-in-Chief following concerns raised after publication. Specifically, duplication of two lanes within the same blot was identified in Figure 1b, where different samples were represented using the same data. The authors were unable to provide a satisfactory explanation or a suitable replacement figure. As a result, the editor has lost confidence in the data and conclusions presented in the study. One author (Swarup Roy Choudhury) disagreed with the retraction. The remaining authors did not respond to correspondence from the publisher regarding this issue.
We present a COI-based assessment of freshwater leeches in Azerbaijan's Lankaran-Astara region. Between 2019 and 2021, we sampled 136 individuals from 33 wetlands across six districts and generated 15 new COI sequences, which were combined with curated GenBank records. Four species were confirmed in three families: Dina lineata (Erpobdellidae), Helobdella stagnalis (Glossiphoniidae), Hirudo orientalis (Hirudinidae), and Trocheta sp. (Erpobdellidae). Azerbaijani D. lineata populations occur as two distinct clades, one that includes an individual from Iraq (Lineage A) and one that includes an individual from Iran (Lineage B). These Asian lineages are separated from European D. lineata. An Azerbaijani Trocheta sp. specimen (FSM20) clusters with one from Iran on a distinct branch that is > 8% divergent from its closest congeners. We suggest this is likely a new species. Our results validate COI barcoding for resolving species boundaries in Caucasian leeches, and highlight the South Caucasus as a promising region for Trocheta diversity and discovery.
