Search Results (603)

Renal oncocytoma (RO) is a benign renal neoplasm characterized by dense accumulation of dysfunctional mitochondria possibly resulting from increased mitochondrial biogenesis and decreased mitophagy; however, the mechanisms controlling these mitochondrial changes are unclear. ROs harbor recurrent inactivating mutations in mitochondrial genes encoding the Electron Transport Chain (ETC) Complex I, and we hypothesize that Complex I loss in ROs directly impairs mitophagy. Our analysis of ROs and normal kidney (NK) tissues shows that a significant portion (8 out of 17) of ROs have mtDNA Complex I loss-of-function mutations with high variant allele frequency (>50%). ROs indeed exhibit reduced Complex I expression and activity. Analysis of the various steps of mitophagy pathway demonstrates that AMPK activation in ROs leads to induction of mitochondrial biogenesis, autophagy, and formation of autophagosomes. However, the subsequent steps involving lysosome biogenesis and function are defective, resulting in an overall inhibition of mitophagy. Inhibiting Complex I in a normal kidney cell line recapitulated the observed lysosomal and mitophagy defects. Our data suggest Complex I loss in RO results in defective mitophagy due to lysosomal loss and dysfunction. Full article

Recurrent pregnancy loss (RPL) is defined as the occurrence of two or more pregnancy losses before 20 weeks of gestation. RPL is a common medical condition among reproductive-age women, with approximately 23 million cases reported annually worldwide. Up to 5% of pregnant women may experience two or more consecutive pregnancy losses. Previous studies have investigated risk factors for RPL, including maternal age, uterine pathology, genetic anomalies, infectious agents, endocrine disorders, thrombophilia, and immune dysfunction. However, RPL is a disease caused by a complex interaction of genetic factors, environmental factors (e.g., diet, lifestyle, and stress), epigenetic factors, and the immune system. In addition, due to the lack of research on genetics research related to RPL, the etiology remains unclear in up to 50% of cases. Platelets play a critical role in pregnancy maintenance. This study examined the associations of platelet receptor and ligand gene variants, including integrin subunit beta 3 (ITGB3) rs2317676 A > G, rs3809865 A > T; fibrinogen gamma chain (FGG) rs1049636 T > C, rs2066865 T > C; glycoprotein 1b subunit alpha (GP1BA) rs2243093 T > C, rs6065 C > T; platelet endothelial cell adhesion molecule 1 (PECAM1) rs2812 C > T; and platelet endothelial aggregation receptor 1 (PEAR1) rs822442 C > A, rs12137505 G > A, with RPL prevalence. In total, 389 RPL patients and 375 healthy controls (all Korean women) were enrolled. Genotyping of each single nucleotide polymorphism was performed using polymerase chain reaction–restriction fragment length polymorphism and the TaqMan genotyping assay. All samples were collected with approval from the Institutional Review Board at Bundang CHA Medical Center. The ITGB3 rs3809865 A > T genotype was strongly associated with RPL prevalence (pregnancy loss [PL] ≥ 2: adjusted odds ratio [AOR] = 2.505, 95% confidence interval [CI] = 1.262–4.969, p = 0.009; PL ≥ 3: AOR = 3.255, 95% CI = 1.551–6.830, p = 0.002; PL ≥ 4: AOR = 3.613, 95% CI = 1.403–9.307, p = 0.008). The FGG rs1049636 T > C polymorphism was associated with a decreased risk in women who had three or more pregnancy losses (PL ≥ 3: AOR = 0.673, 95% CI = 0.460–0.987, p = 0.043; PL ≥ 4: AOR = 0.556, 95% CI = 0.310–0.997, p = 0.049). These findings indicate significant associations of the ITGB3 rs3809865 A > T and FGG rs1049636 T > C polymorphisms with RPL, suggesting that platelet function influences RPL in Korean women. Full article

Recurrent pregnancy loss (RPL) is defined as the occurrence of two or more consecutive pregnancy losses before 20 weeks of gestation, encompassing both embryonic and fetal losses. Although previous studies have provided substantial insights into RPL, the causes in many cases remain unexplained. This lack of information has prompted continued investigation into various risk factors, including those identified through next-generation sequencing (NGS). In the present study, whole-exome sequencing (WES) was used to identify genes potentially associated with RPL and infertility, which may serve as novel biomarkers. Confirmation of the association between these genetic variants and RPL may help to develop functional biomarkers for early diagnosis. The findings revealed that the PCSK5 rs1110222 G > A polymorphism was significantly associated with a reduced risk of RPL. In contrast, the MUC2 rs10902088 C > T polymorphism was associated with an increased risk of RPL among women with more than four pregnancy losses. Notably, the A-T allele combination of PCSK5 rs1110222 G > A and MUC2 rs10902088 C > T showed a significant association with a decreased risk of RPL relative to the G-C combination. In conclusion, this study confirms that the PCSK5 rs1110222 G > A and MUC2 rs10902088 C > T polymorphisms are genetically associated with the prevalence of RPL in Korean women. Full article

GATA3 is a transcription factor involved in urothelial differentiation and is widely used as a diagnostic marker for urothelial carcinoma (UC). Although loss of GATA3 expression has been linked to more aggressive disease, its prognostic significance remains uncertain. Genetic variation within the GATA3 locus, particularly rs1244159, may influence protein expression and clinical outcomes. We conducted a case control study in Taiwan including 461 UC cases and 586 controls genotyped for four GATA3 SNPs. GATA3 expression was assessed via immunohistochemistry (IHC) in 98 tumor tissues. Logistic regression and Kaplan–Meier analyses were used to evaluate SNP associations and survival outcomes. An XGBoost-based machine learning model with SHAP (SHapley Additive exPlanations) was applied to rank survival predictors. The rs1244159 G allele was associated with a significantly reduced UC risk (adjusted OR = 0.48, p = 0.0231) and higher GATA3 expression (p = 0.0173). High GATA3 expression predicted improved overall survival (p = 0.0092), particularly among G allele carriers (p = 0.0071). SHAP analysis identified age, chemotherapy, and GATA3 expression as the top predictors of survival, consistent with Cox regression results. In conclusion, our integrative analysis suggests that the rs1244159 G allele modulates GATA3 expression and influences UC prognosis. Combining genomics, pathology, and machine learning, GATA3 may serve as a clinically useful biomarker for risk stratification and outcome prediction in UC. Full article

The domestication process not only reduced the allelic diversity of tomato genotypes but also affected the genetic traits associated to microbial recruitment, their composition, and their diversity in different compartments of the plant host. Additionally, this process included the transition from natural to agricultural soils, which differ in nutrient availability, physicochemical properties, and agricultural practices. Therefore, modern cultivars may fail to recruit microbial taxa beneficial to their wild relatives, potentially losing important ecological functions. In this study, we analyzed the phylogenetic relationship and the rhizosphere microbiota of four tomato genotypes, Solanum chilense (wild species), S. lycopersicum var. cerasiforme (Cherry tomato), and the S. lycopersicum landrace ‘Poncho Negro’ and the modern cultivar ‘Cal Ace’, grown in both natural and agricultural soils. Microbial communities were identified using 16S rRNA (bacteria) and ITS2 (fungi) amplicon sequencing, allowing cross-domain taxonomic characterization. While the soil type was the main driver of overall microbial diversity, the host genotype influenced the recruitment of specific microbial taxa, which exhibited different recruitment patterns according to the genetic diversification of Solanum genotypes and soil types. Additionally, co-occurrence network analysis identified two main clusters: first, taxa did not show any preferential associations to particular genotypes or soil types, while the second cluster revealed specific microbial patterns associated to fungal taxa in natural soil and bacterial taxa in agricultural soil. Finally, the functional analysis suggested the loss of specific functions through tomato domestication independently of soil type. These findings highlight the role of the plant genotype as a fine-tuning factor in microbiome assembly, with implications for breeding strategies aimed at restoring beneficial plant–microbe interactions. Full article

Rice is a staple food for over half of the world’s population, and it is grown in over 100 countries. Rice blast disease can cause 10% to 30% crop loss, enough to feed 60 million people. Breeding for resistance can help farmers avoid costly fungicides. This study assessed the relationship between rice blast disease and zinc or anthocyanin content in biofortified rice. Susceptibility to foliar and panicle blast was assessed in a rice panel which differed on grain zinc content and pigmentation. A rice panel (n = 23) was challenged with inoculum of two isolates of Magnaporthe oryzae in a screenhouse-based assay. The zinc content with foliar blast severity was analyzed in the leaves and grain of a subset of non-inoculated rice plants. The effect of foliar zinc supplementation on seedlings was assessed by varying levels of zinc fertilizer solution on four blast susceptible cultivars at 14 days after planting (DAP), followed by inoculation with the blast pathogen at 21 DAP. Foliar blast severity was scored on a 0–9 scale at 7 days after inoculation. The rice panel was scored for anthocyanin content, and the data were correlated with foliar blast severity. The panel was grown in the field, and panicle blast, grain yield and yield-related agronomic traits were measured. Significant differences were observed in foliar blast severity among the rice genotypes, with IRBLK-KA and IR96248-16-2-3-3-B having mean scores greater than 4, as well as BASMATI 370 (a popular aromatic variety), while the rest of the genotypes were resistant. Supplementation with foliar zinc led to a significant decrease in susceptibility. A positive correlation was observed between foliar and panicle blast. The Zn in the leaves was negatively correlated with foliar blast severity, and had a marginally positive correlation with panicle blast. There was no relationship between foliar blast severity and anthocyanin content. Grain yield had a negative correlation with panicle blast, but no correlation was observed between Zn in the grain and grain yield. This study shows that Zn biofortification in the grain may not enhance resistance to foliar and panicle blast. Furthermore, the zinc-biofortified genotypes were not agronomically superior to the contemporary rice varieties. There is a need to apply genomic selection to combine promising alleles into adapted rice genetic backgrounds. Full article

Background/Objectives: Standardbreds, a breed of horses used in harness racing at either the trot or the pace, established a closed studbook in 1973. Concerns about genetic diversity within the breed led the United States Trotting Association (USTA) to establish a limit of mares bred per stallion (i.e., a studbook cap) in 2009. Here, we aimed to evaluate the impact of the breeding restrictions on genetic diversity between and among subpopulations. Methods: Sixteen short tandem repeats (STRs) were analyzed across a dataset of 176,424 Standardbreds foaled in the United States between 1998 and 2021. We examined allelic richness (Na), number of effective alleles (Ne), expected heterozygosity (H_E), observed heterozygosity (H_O), inbreeding coefficient (F_IS), and fixation index (F_ST) across 24 years, differentiating by gate type, and comparing pre-(1998–2009) and post-(2010–2021) studbook cap periods using regression analysis. Results: Our results support decreased genetic diversity for both trotters and pacers over time. However, pacing Standardbreds exhibited significantly slower rates of decrease in genetic diversity after the 2009 studbook cap, as evidenced by Ne, H_E, and F_IS (P_Bonferroni < 0.01). Additionally, moderate levels of genetic differentiation were found between trotters and pacers (0.05 < F_ST < 0.09), which increased over time. Conclusions: Given that the rate of loss of diversity does not appear to differ pre and post studbook cap in trotters and that there is an increase in genetic differentiation between the groups over time, developing additional breeding tools and strategies is necessary to help the subpopulation mitigate further decline. Full article

The AP2/ERF transcription factor ABSCISIC ACID INSENSITIVE 4 (ABI4) plays diverse roles in plant development and responses to abiotic stress. However, its potential involvement in regulating anthocyanin biosynthesis is not fully understood. In this study, three different loss-of-function abi4 alleles (abi4-1, abi4-2, and abi4-101) were employed to investigate the role of ABI4 in the regulation of anthocyanin accumulation in Arabidopsis seedlings. These abi4 mutants exhibited significantly increased anthocyanin accumulation, which was associated with elevated expression of genes involved in anthocyanin biosynthesis. HY5 (LONG HYPOCOTYL 5), a central component of photomorphogenesis, acts as a key light-regulated molecular switch. Further analysis revealed that ABI4 requires HY5 to function as a negative regulator of anthocyanin biosynthesis. Additionally, loss of ABI4 resulted in heightened light sensitivity, leading to increased light-induced chlorophyll accumulation and chloroplast development, along with upregulation of photosynthesis-related genes. Interestingly, the light-hypersensitive phenotype of abi4 mutants was partially rescued by the loss of HY5 function. Taken together, these findings demonstrate that ABI4 negatively regulates anthocyanin accumulation in Arabidopsis seedlings through a HY5-dependent light signaling pathway. Full article

The sterol demethylation inhibitors (DMIs) are among the most widely used fungicides for controlling black Sigatoka (Mycosphaerella fijiensis) and yellow Sigatoka (Mycosphaerella musicola) in banana plantations in Brazil. Black Sigatoka is considered more important due to causing yield losses of up to 100% in commercial banana crops under predisposing conditions. In contrast, yellow Sigatoka is important due to its widespread occurrence in the country. This study aimed to determine the current sensitivity levels of Mf and Mm populations to DMI fungicides belonging to the chemical group of triazoles. Populations of both species were sampled from commercial banana plantations in Registro, Vale do Ribeira, São Paulo (SP), Ilha Solteira, Northwestern SP, and Janaúba, Northern Minas Gerais, and were further characterized phenotypically. Additionally, allelic variation in the CYP51 gene was analyzed in populations of these pathogens to identify and characterize major mutations and/or mechanisms potentially associated with resistance. Sensitivity to the triazoles propiconazole and tebuconazole was determined by calculating the 50% inhibitory concentration of mycelial growth (EC₅₀) based on dose–response curves ranging from 0 to 5 µg mL⁻¹. Variation in sensitivity to fungicides was evident with all nine Mf isolates showing moderate resistance levels to both propiconazole or tebuconazole, while 11 out of 42 Mm strains tested showed low to moderate levels of resistance to these triazoles. Mutations leading to CYP51 substitutions Y136F, Y461N/H, and Y463D in Mm and Y461D, G462D, and Y463D in Mf were associated with low or moderate levels of resistance to the triazoles. Interestingly, Y461H have not been reported before in Mm or Mf populations, and this alteration was found in combination with V106D and A446S. More complex CYP51 variants and CYP51 promoter inserts associated with upregulation of the target protein were not detected and can explain the absence of highly DMI-resistant strains in Brazil. Disease management programs that minimize reliance on fungicide sprays containing triazoles will be needed to slow down the further evolution and spread of novel CYP51 variants in Mf and Mm populations in Brazil. Full article

Epilepsy is one of the most common neurological disorders. Disease etiology and pathogenesis are still not well understood. Genetic mutations are associated with 70% of epilepsies, while 30% are still enigmatic. Attempting to close the knowledge gap, we performed genetic analysis of a cohort of patients from the Middle East and North Africa, both understudied and highly consanguineous populations. Whole exome sequencing (WES) was carried out on 81 patients and their family members at a tertiary center in Qatar. We found damaging mutations in half of the patients: 15 in known epilepsy genes, and 19 in contested or unknown genes. The mutations include single nucleotide polymorphisms (SNVs), frameshifts, copy number variations (CNVs), and loss of homozygosity (LOH). Fifteen of the SNVs are novel, and seventeen are homozygous, reflective of the characteristics of the cohort. In addition, we used the WES data to type HLA alleles for 13 class I and II genes. We show that DRB3*01:01:02G is negatively associated with epilepsy, in contrast to DRB4*01:01:01G, which may be a risk allele. In addition to expanding the knowledge base of genes involved in epilepsy, our findings show that genetic predisposition, inclusive of immune genes, suggests a complex etiology. Full article

The Lutjanidae family includes multiple species highly important to the global fishing industry. In Brazil, approximately 40% of the fishing landings come from a species of this family, the dog snapper, Lutjanus jocu, among the most abundant in the northeast-region fisheries. This study aimed to analyze the genetic diversity and population structure of this species in the states of Bahia and Espírito Santo through the use of microsatellite markers. The dog snapper presented a high genetic variability in the studied populations, with the presence of a distinct population stock in northern Bahia probably driven by habitat suitability, larvae retention, and fishing pressure. The L. jocu sampling sites exhibited an excess of heterozygosity, a low allelic richness, and M-ratio values close to critical levels, probably indicating a recent population decline. Additionally, the low inbreeding indices and high genetic diversity values suggest a significant connectivity and considerably effective population sizes. Although these characteristics may reflect population stability, anthropogenic factors such as habitat loss, fragmentation, and overfishing may pose threats to the sustainability of the species, particularly along the northeastern coast of Brazil. Full article

Background: The etiopathogenesis of atopic dermatitis is complicated, and it includes aspects such as dysfunction of the skin barrier, changes in immune responses, IgE-mediated hypersensitivity, and many characteristics of the environment. Regarding skin barrier dysfunction, a number of genetic changes have been described. This genetic predisposition could be related to the phenotypes of atopic dermatitis. Aim: In this study, several polymorphisms in five proinflammatory genes were associated with certain phenotypes of AD patients (genotype–phenotype study). Methods: In total, 89 unrelated AD Czech (Caucasian) patients were genotyped regarding five proinflammatory gene polymorphisms (angiotensinogen AGT M235T, AGT-6 G/A, TNF-α-238 G/A, TNF-β Fok1, IL-6-174 C/G and IL-6-596 G/A). Genotyping was performed using PCR and restriction analysis. For phenotypes, patients’ sex, age and personal and family history of atopy, aero- and food allergies and other complex diseases were evaluated. Results: A significant association with transepidermal water loss (TEWL) measured on the forearm was found with the AGT M235T polymorphism (p = 0.02). For the AG genotype of TNF-α-238 G/A, a six-times higher risk for a family history of diabetes mellitus compared to other examined aspects of family history was found (p = 0.02). A family history of thyreopathy was associated with the IL-6-174 G/C polymorphism when compared to a family history of other complex diseases. The GG genotype had a ten-times higher risk for a family history of thyreopathy compared to the other genotypes (p = 0.004). This result was highly specific (0.914). The GG genotype of IL-6-596 G/A was associated with a family history of thyreopathy, with the same result (p = 0.004). Moreover, the G allele of IL-6-174 G/C was associated with a family history of thyreopathy compared to AD patients without a positive family history of complex diseases (p = 0.03). In AD men, the MM genotype of the AGT M235T gene was found to be associated with food allergies (p = 0.004). This result was highly sensitive (0.833). A family history of cardiovascular disease in AD men was associated with AGT-6 G/A variability. The A allele was found to be six times more frequent in patients with a positive family history of cardiovascular disease (p = 0.02, with high sensitivity and specificity (0.700 and 0.735, respectively)). A family history of diabetes mellitus was associated with the TNF-β Fok1 polymorphism, where the B1 allele was almost six times more frequent in AD men with a positive family history of diabetes mellitus (p = 0.02), with high sensitivity (0.85). A significant association between TEWL measured on the forearm and the AGT M235T polymorphism was found when AD women were carriers of the MM genotype, with a median of 25 and range 4–61; those patients with the MT genotype had a median of 10 and range of 0.3–39; and patients with the TT genotype had a median of 5 and range of 3–40, p = 0.003. The polymorphism AGT-6 G/A was associated with different ages of eczema onset. The AG genotype was almost nine times more risky for the youngest group (0–7 years) compared to the oldest group (more than 18 years) (p = 0.02), with high specificity for this result. Conclusions: Our results in the field of cytokine signaling in the immune system in patients with atopic dermatitis are in agreement with those of GWASs. We suggest that cost-effective and simple PCR tests may be the best approach for the rapid and optimal collection of valid genetic information in clinical practice. Full article

Genomic imprinting is critical for mammalian development, but its regulation varies across species. The insulin-like growth factor 2 receptor (IGF2R), which is a maternally expressed imprinted gene critical for cell proliferation and differentiation, as well as embryonic and placental development, is classically regulated by differentially methylated regions (DMRs) and lncRNA-Airn in mice. However, studies on this in equus are scarce, especially in terms of mechanistic studies. In the present study, heart, liver, spleen, lung, kidney, brain, and muscle samples were obtained from horses, donkeys, and hybrids, and gene expression and imprinting state were tested to investigate the imprinting regulation of Igf2r in these animals. Bisulfite sequencing combined with an allele-specific expression analysis revealed a tissue-specific loss of imprinting in the mule liver and hybrid brain tissues. Strikingly, we found that the maternal-specific expression of equine Igf2r did not rely on the canonical DMRs or lncRNA-Airn. Surprisingly, DNA methylation of a specific region called CpG island 2 (CpGI2) in the Igf2r promoter showed cis-acting inheritance, meaning that the DNA methylation patterns of the parental alleles are retained in hybrid tissues. Notably, the DNA methylation of CpGI2 correlated negatively with Igf2r expression in the spleen (R² = 0.8797, p = 6.46 × 10⁻⁶), lung (R² = 0.8569, p = 1.57 × 10⁻⁵), and kidney (R² = 0.8650, p = 3.85 × 10⁻⁶). Our findings suggest that imprinting may work differently in other species. This study provides a framework for understanding imprinting diversity in hybrids and shows that equine hybrids can be used to study how epigenetic inheritance works. Full article

Background/Objectives: Pathogenic recessive GJB2 variants are the main genetic cause of non-syndromic sensorineural hearing loss. However, following GJB2 testing, a significant proportion of deaf patients are only found to be heterozygous carriers of pathogenic GJB2 alleles. Five large deletions not affecting GJB2 but encompassing a minimal common 62 kb region within the neighbouring CRYL1 gene have been described to cause loss of cis GJB2 expression and, as a result, produce hearing loss when in trans with pathogenic GJB2 variants. We describe the identification and characterization of a novel deletion of this type in deaf patients from northwestern Spain. Methods: We used panel NGS sequencing to detect the deletion, MLPA to validate it, whole-genome sequencing to map its breakpoints, PCR + Sanger sequencing to finely characterize it and triple-primer PCR to screen for it. Results: We identified a novel 200 kb deletion spanning the whole CRYL1 gene in two unrelated deaf patients from Asturias (in northwestern Spain) who were heterozygous for the pathogenic GJB2 c.35delG variant. Although the large deletion was absent from gnomAD v4.1.0 and 2052 local control alleles, screening for it in 20 additional deaf carriers of monoallelic pathogenic GJB2 variants detected it in another patient from Galicia (also in northwestern Spain). The novel deletion, termed del(200 kb)insATTATA, explained hearing loss in 3/43 (7%) deaf patients from our cohort that were otherwise heterozygous for pathogenic GJB2 variants. Conclusions: This work highlights the importance of comprehensively testing all genomic regions known to be clinically relevant for a given genetic condition, including thorough CRYL1 CNV screening for DFNB1A diagnostics. Full article

Background/Objectives: The prevalence of dementia among South Asians across India is high among those who are 65 years and older, yet little is known about genetic risk factors for dementia in this population. Methods: Using whole-genome sequence data from 2680 participants from the Diagnostic Assessment of Dementia for the Longitudinal Aging Study of India (LASI-DAD), we performed a gene-based analysis on the missense/loss-of-function (LoF) and brain-specific promoter/enhancer variants of 84 genes, previously associated with AD in European Ancestry (EA). These analyses were performed separately, both with and without incorporating additional annotation weights (e.g., deleteriousness, conservation scores), using the variant-Set Test for Association using Annotation infoRmation (STAAR). We investigated associations with the Hindi Mental State Examination (HMSE) score and factor scores for general cognitive function and five cognitive domains. Results: In the missense/LoF analysis, without annotation weights and controlling for age, sex, state/territory, and genetic ancestry, three genes were associated with at least one measure of cognitive function (FDR q < 0.1). APOE was associated with four measures of cognitive function, PICALM was associated with HMSE score, and TSPOAP1 was associated with executive function. The most strongly associated variants in each gene were rs429358 (APOE ε4), rs779406084 (PICALM), and rs9913145 (TSPOAP1). Rs779406084 is a rare missense mutation that is enriched in LASI-DAD compared to EA (minor allele frequency = 0.075% vs. 0.0015%). Conclusions: Missense/LoF variants in some genes previously associated with AD in EA are associated with measures of cognitive function in South Asians from India. Analyzing genome sequence data allows the identification of potential novel causal variants enriched in South Asians. Full article