Olga V. Kochetova

MicroRNAs (miRNAs) are involved in the regulation of glucose metabolism and inflammatory processes associated with type 2 diabetes (T2D) and have potential as biomarkers and therapeutic targets. We analysed the expression of miR-155-5p, miR-141-3p, miR-15b-5p, miR-18a-5p, and miR-379-5p in peripheral blood mononuclear cells (PBMCs) from 79 patients with T2D and 88 non-diabetic controls. Differential expression analysis revealed significant downregulation of miR-15b-5p, miR-155-5p, and miR-18a-5p, and significant upregulation of miR-379-5p in T2D patients. Among the individual miRNAs, miR-15b-5p showed the highest ability to distinguish between T2D and controls (AUC = 0.82, 95% CI 0.76–0.89, p = 0.001). A model combining the four differentially expressed miRNAs (miR-155-5p, miR-15b-5p, miR-18a-5p, and miR-379-5p) with age, sex, and BMI had an AUC of 0.98, compared with 0.93 for age, sex, and BMI alone (p = 0.004, paired DeLong test); the optimism-corrected AUC was 0.97, although the bootstrap procedure did not account for optimism arising from miRNA selection. Functional enrichment analysis identified MAPK, Hippo, FoxO, insulin, AMPK and TGF-β signalling as consistently enriched across analyses based on experimentally supported and predicted miRNA targets.

Intensive selection and inbreeding in farm bird populations (Gallus gallus domesticus) lead to reduced genetic diversity, a decrease in effective population size, and the loss of rare alleles. Biobanks of genetic resources serve as repositories for gene pool conservation, ensuring the recording of allele frequencies, haplotype profiles, and population structure. This review presents a comprehensive analysis of the status and prospects for biobanking of farm bird genetic resources as a strategic tool for preserving biodiversity and accelerating breeding progress. The review discusses the types of biobanks and the biological material they preserve, describes the features of cryopreservation in birds, examines key international and domestic centers and global initiatives for the conservation of animal genetic material, and provides an interdisciplinary analysis of biobanking of avian genetic resources in the context of epidemiological safety, regulatory frameworks, and technological development prospects. Particular attention is paid to Russian collections of chicken biological material with verified phenotypes as well as integration with international FAO/ERFP/EUGENA standards within the framework of the “One Health/One Biodiversity” concept.

Background/Objectives: Chronic obstructive pulmonary disease (COPD) is increasingly viewed as a disorder of impaired cellular adaptation to chronic stress, involving oxidative injury, mitochondrial dysfunction, and accelerated cellular senescence. We investigated whether genetic variation in these pathways contributes to disease susceptibility, lung function impairment, and polygenic risk prediction. Methods: Thirty-three single-nucleotide variants were analysed in 747 patients with COPD and 703 controls. Associations with disease susceptibility and lung function parameters were assessed using regression models with correction for multiple testing. Weighted and unweighted polygenic scores were constructed from associated variants and evaluated using receiver operating characteristic and net reclassification improvement analyses. Results: Significant associations were identified in genes involved in antioxidant defence (NFE2L2, HMOX1, GSR), PI3K/AKT/mTOR signalling (PIK3R1, PTEN), mitochondrial function (TOMM40), cellular stress responses (FOXO3A), and long non-coding RNA regulation (MEG3, CDKN2B-AS1). The strongest association was observed for PIK3R1 rs831125 (OR = 2.31, p = 2.53 × 10⁻¹⁰). Variants in NFE2L2, PIK3R1, MEG3, MALAT1, and SIRT3 were additionally associated with pulmonary function parameters. The weighted polygenic score demonstrated good discriminative ability (AUC 68.8%, 95% CI 65.9–71.7%) and substantially improved prediction when combined with age, sex, and smoking exposure (AUC 88.1%, 95% CI 86.3–89.8%; NRI = 0.62, p = 2.21 × 10⁻²⁸). Conclusions: The identified loci converge on interconnected pathways involved in cellular stress adaptation, mitochondrial homeostasis, and senescence, supporting their contribution to chronic obstructive pulmonary disease susceptibility and functional decline.

Egg production in Gallus gallus domesticus represents a complex, economically critical trait shaped by multiple interrelated phenotypes, including age at first egg, total egg number, egg weight, and clutch characteristics. These traits are governed by polygenic inheritance and modulated by environmental factors, making the dissection of their genetic architecture essential for improving breeding efficiency, particularly under the emerging “long-life layers” production model. This systematic review aimed to integrate current knowledge on the genetic and molecular basis of egg production traits through analysis of genome-wide association studies and related genomic approaches. A structured literature search identified 27 eligible studies, which were evaluated following PRISMA guidelines. Data extraction and meta-analysis were conducted using standardized genome annotations and computational pipelines. The synthesis of available evidence demonstrates moderate to high heritability for key reproductive traits and highlights consistent genomic signals across multiple chromosomes. Importantly, the findings reveal a shift toward a systems-level understanding of egg production, involving conserved biological pathways related to neuroendocrine regulation, folliculogenesis, and energy metabolism. The integration of diverse genomic approaches enables the development of more precise, breed-specific selection strategies. Overall, these advances support a transition from traditional selection toward molecularly informed breeding frameworks, with significant implications for productivity, sustainability, and global food security.

Abdominal fat deposition in chickens significantly impacts production efficiency and is influenced by complex genetic and molecular mechanisms. This review summarizes current genomic and transcriptomic research on the regulation of adipogenesis and fat accumulation in chickens, highlighting key genes and loci identified through genome-wide association studies as well as other candidates involved in lipogenesis, lipolysis, and transcriptional regulation. Major metabolic pathways, including MAPK, AMPK, PI3K/AKT/mTOR, TGFβ1/Smad3, FoxO, JAK–STAT, Wnt/β-catenin, and Sonic Hedgehog signaling, are examined for their roles in fat deposition. The regulatory functions of non-coding RNAs, including microRNAs, long non-coding RNAs, and circular RNAs, are discussed, focusing on their interactions with target mRNAs and signaling networks that control lipid metabolism, adipocyte differentiation, and energy balance. Integrating insights from both avian and human studies, this review emphasizes the molecular mechanisms underlying adipogenesis and highlights potential strategies for genetic selection aimed at reducing excessive abdominal fat and improving poultry productivity.

Background/Objectives: Type 2 diabetes (T2D) is a clinically and genetically heterogeneous disease. In this study, we aimed to stratify patients with T2D from the Volga-Ural region of Eurasia into distinct subgroups based on clinical characteristics and to investigate the genetic underpinnings of these clusters. Methods: A total of 254 Tatar individuals with T2D and 361 ethnically matched controls were recruited. Clinical clustering was performed using k-means and hierarchical algorithms on five variables: age at diagnosis, body mass index (BMI), glycated hemoglobin (HbA1c), insulin resistance (HOMA-IR), and β-cell function (HOMA-B). Genetic association analysis was conducted using logistic regression under an additive model, adjusted for age and sex, and corrected for multiple comparisons using the Benjamini–Hochberg method. Results: Four distinct T2D subtypes were identified—mild age-related diabetes (MARD, n = 25), mild obesity-related diabetes (MOD, n = 72), severe insulin-resistant diabetes (SIRD, n = 66), and severe insulin-deficient diabetes (SIDD, n = 52)—each with unique clinical and comorbidity profiles. SIDD patients exhibited the highest burden of microvascular complications and lowest estimated glomerular filtration rate. Nine genetic variants showed significant associations with T2D and/or specific subtypes, including loci in genes related to neurotransmission (e.g., HTR1B, CHRM5), appetite regulation (NPY2R), insulin signaling (TCF7L2, PTEN), and other metabolic pathways. Some variants demonstrated subtype-specific associations, underscoring the genetic heterogeneity of T2D. Conclusions: Our findings support the utility of clinical clustering in uncovering biologically and clinically meaningful T2D subtypes and reveal genetic variants that may contribute to this heterogeneity. These insights may inform future precision medicine approaches for T2D diagnosis and management.

The appetite of adult humans can be characterized by means of Adult Eating Behavior Questionnaire (AEBQ), adapted from Children’s Eating Behavior Questionnaire (CEBQ). The AEBQ questionnaire is validated in many countries. Objective. To validate the Russian-language version of the AEBQ_Rus questionnaire, confirm the factor structure and evaluate the internal consistency of all subscales of the questionnaire, as well as to study the associations between the level of body mass index and subscales of the questionnaire. Materials and methods. Convergent validity was studied and a correlation between the AEBQ_Rus subscales and the level of body mass index (BMI) was determined in order to evaluate the criterion validity. The study participants were medical university’s students (n=576, mean age 20.11±1.87 years), who provided demographic and anthropometric data and answered questions of the Russian-language version of the AEBQ_Rus questionnaire. Results. High internal consistency of the final factor structure of the AEBQ_Rus questionnaire has been shown (Cronbach’s α=0.75). Statistically significant correlations between the AEBQ_Rus subscales have been shown, correlation between BMI levels and «Emotional overeating» and «Eating pleasure» subscales has been established using linear regression analysis and in assessment of Pearson correlation at the trend level. Conclusion. This study is the first step in investigating the use of the Russian-language version of the AEBQ_Rus questionnaire as a valid and reliable tool for measuring a wide range of appetite features in persons of the Russian-speaking population.

The poultry industry, a globally fast growing agricultural sector, provides affordable animal protein due to high efficiency. Gallus gallus domesticus are the most common domestic birds. Hybrid chicken breeds (crosses) are widely used to achieve high productivity. Maintaining industry competitiveness requires constant genetic selection of parent stock to improve performance traits. Genetic studies, which are essential in modern breeding programs, help identify genome variants linked to economically important traits and preserve population health. Next-generation sequencing (NGS) has identified millions of single nucleotide polymorphisms (SNPs) and insertions/deletions (INDELs), enabling detection of genome-wide regions associated with selection traits. Recent studies have pinpointed such regions using broiler lines, laying hen lines, or pooled genomic data. This review discusses advances in chicken genomic and transcriptomic research focused on traits enhancing meat breed performance and reproductive abilities. Special attention is given to transcriptome studies revealing regulatory mechanisms and key signaling pathways involved in artificial molting, as well as metagenome studies investigating resistance to infectious diseases and climate adaptation. Finally, a dedicated section highlights CRISPR/Cas genomic editing techniques for targeted genome modification in chicken genomics.

Obesity and addictive eating behaviors represent significant causal factors in the development of type 2 diabetes mellitus. Genes encoding muscarinic and nicotinic receptors have been demonstrated to be significantly associated with a wide range of psychiatric disorders. Consequently, these genes represent potential markers for the study of predisposition to both disturbed eating behavior and type 2 diabetes mellitus (T2DM). A total of 992 DNA samples from individuals with T2DM and 1023 DNA samples from healthy controls were examined. A DEBQ-based assessment of eating behavior was conducted. The following polymorphic loci were investigated by real-time PCR: CHRNA5 (rs16969968), CHRNA3 (rs1051730), CHRNB4 (rs17487223), CHRM4 (rs206748), CHRNA3 (rs578776), CHRM5 (rs7162140), CHRM1 (rs2067477), CHRNA7 (rs3826029). The present study found an association between the T2DM and the following genetic variants: CHRNA5 rs16969968 (P = 0.0004, OR = 1.72), CHRNA3 rs1051730 (P = 0.00001, OR = 1.25), CHRM5 rs7162140 (P = 0.051, OR = 1.90), and CHRM1 rs2067477 (P = 0.009, OR = 1.41). An association was shown between the AA haplotype (CHRNA5 rs16969968–CHRNA3 rs1051730) and the AAT haplotype (CHRNA5 rs16969968–CHRNA3 rs1051730–CHRNB4 rs17487223) with development of T2DM (P = 0.0004, OR = 1.37; P = 0.00005, OR = 1.34). The CHRNA3 rs578776, CHRNA7 rs3826029, CHRM5 rs7162140, and CHRM1 rs2067477 loci were found to be associated with restrictive eating behavior (P = 0.05, 0.003, 0.015, 0.05 respectively). Additionally, the CHRM1 rs2067477 locus was found to be associated with emotional eating behavior (P = 0.014), while the CHRNA5 rs16969968 and CHRNB4 rs17487223 gene polymorphisms were found to be associated with external eating behavior (P = 0.05, P = 0.036). The study revealed an association between polymorphic variants of the studied genes and both disturbed eating behavior and T2DM.

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