Background: Breast cancer (BC) is the most common cancer among women worldwide. At present, there is a need to search for new, accurate, reliable, minimally invasive and cheap biomarkers in addition to existing methods for the diagnosis and prognosis of BC. The main goal of this study was to test the diagnostic value of six circulating miRNAs in Kazakh women. Materials and methods: TaqMan-based miRNA profiling was conducted using plasma specimens from 35 BC women patients and 33 healthy women samples (control group). Results: The level of all seven miRNAs (including endogenous control) normalized by synthetic cel-miR-39 were significantly elevated in the group of BC patients. Normalization using miR-222-3p as endogenous control reduced differences in level of miRNAs between groups; as a result, only three miRNAs were significantly upregulated in the group of BC patients—miR-145-5p (P = 6.5e−12), miR-191-5p (P = 3.7e−10) and miR-21-5p (P = 0.0034). Moreover, ROC analysis showed that the use of miR-145-5p and miR-191-5p, both individually (AUC = 0.931 and 0.904, respectively) or in combination (AUC = 0.984), allows to accurately differentiate BC patients from healthy individuals. Conclusions: Two plasma miRNAs—miR-145-5p and miR-191-5p—are potential biomarkers for diagnosis of BC in the Kazakh population. The findings need to be further substantiated using a more representative sample.

The variability of nucleotide repeats is considered one of the causes of diseases, but their biological function is not understood. In recent years, the interaction of miRNAs and piRNAs with the mRNAs of genes responsible for developing neurodegenerative and oncological diseases and diabetes have been actively studied. We explored candidate genes with nucleotide repeats to predict associations with miRNAs and piRNAs. The parameters of miRNAs and piRNA binding sites with mRNAs of human genes having nucleotide repeats were determined using the MirTarget program. This program defines the start of the initiation of miRNA and piRNA binding to mRNAs, the localization of miRNA and piRNA binding sites in the 5′-untranslated region (5′UTR), coding sequence (CDS) and 3′-untranslated region (3′UTR); the free energy of binding; and the schemes of nucleotide interactions of miRNAs and piRNAs with mRNAs. The characteristics of miRNAs and piRNA binding sites with mRNAs of 73 human genes were determined. The 5′UTR, 3′UTR and CDS of the mRNAs of genes are involved in the development of neurodegenerative, oncological and diabetes diseases with GU, AC dinucleotide and CCG, CAG, GCC, CGG, CGC trinucleotide repeats. The associations of miRNAs, piRNAs and candidate target genes could be recommended for developing methods for diagnosing diseases, including neurodegenerative diseases, oncological diseases and diabetes.

Data on the genetic polymorphism of 27 Y-STR in Kazakhs of the Junior Zhuz has been presented and analyzed in relation to forensic features. A total of 464 representatives of the Western Kazakh tribes of Kazakhstan (Western Kazakhs, n = 405) and Uzbekistan (Karakalpakstan Kazakhs, n = 59) were examined by the Yfiler Plus set. The data are available in the YHRD under accession numbers YA006010 and YA006009. Genetic analysis (AMOVA and MDS) did not show significant differences between the two groups (Kazakhstan and Karakalpakstan Kazakhs) in terms of Y-chromosome diversity. Both groups are characterized by haplogroup C2a1a2 as a founder effect, which dominated two of the three tribes: Alimuly (67%), Baiuly (74.6%), and Zhetiru (25.8%). At the same time, the phylogenetic network for each tribe found its own clusters within C2a1a2. Western Kazakhs and Karakalpakstan Kazakhs present high values of unique haplotypes (84.44% and 96.61%), discrimination capacity (90.37% and 98.30%), and haplotype diversity (0.9991 and 0.9994). A set of 27 Y-STR loci distinguishes closely related individuals within the Western Kazakh tribes quite well. It is suitable for forensic application, and is also optimal for population genetics studies.

Currently, recurrent implantation failure (RIF) after in vitro fertilization is a problem that is commonly faced by reproductive specialists. The phenomenon of a thin endometrium in RIF patients is not yet completely understood or sufficiently treated. This study aimed to reveal the dysregulated expression of selected genes between RIF patients with a thin endometrium and fertile women. Endometrial samples were collected in the implantation window (21–24 days of the natural menstrual cycle) from RIF patients (n = 20) and fertile women (n = 14). Ten genes were chosen as target genes regarding their possible relations with the implantation process. The endometrial gene expression levels showed differences in RIF samples compared to fertile samples. Significant downregulation was observed for the CXCL1 (p = 0.005) and C4BPA (p = 0.03) genes. There was no statistically significant difference between the RIF group and the fertile group in the expression of eight genes: CXCL8, HPRT1, MMP10, INFG, VEGFB, HAND2, IL-15, and TNC (p > 0.05). The use of a combination of two markers (C4BPA + CXCL1) allows for the good discrimination of RIF patients from fertile women (AUC 0.806).

Background: The differential diagnosis of tuberculosis (TB) and lung cancer (LC) is often challenging due to similar clinicopathological presentations when bacterial shedding is negative, which can lead to delays in treatment. In this study, we tested the potential of plasma-circulating microRNAs (miRNAs) for the early and differential diagnosis of TB and LC. Methods: We conducted a two-phase study: profiling 188 miRNAs in pooled plasma samples and validating 14 selected miRNAs in individual plasma samples from 68 LC patients, 38 pulmonary TB patients, and 41 healthy controls. Results: Twelve miRNAs were significantly elevated in LC patients compared to controls and TB patients, while two miRNAs were significantly elevated in TB patients compared to controls. ROC analysis demonstrated that miR-130b-3p, miR-1-3p, miR-423-5p, and miR-200a-3p had good discriminatory ability to distinguish LC patients (including those with stage I tumours) from healthy individuals and miR-130b-3p, miR-423-5p, miR-15b-5p, and miR-18b-5p effectively distinguished LC patients (including those with stage I tumours) from TB patients. Additionally, miR-18b-5p showed good discriminatory ability between SCLC and NSCLC patients. Conclusions: Circulating miRNAs hold strong potential for the early detection of LC and for distinguishing LC from TB.

Background and Objectives: Nowadays, every tenth adult in the world suffers from diabetes mellitus (DM). Diabetic retinopathy (DR) is the most common microvascular complication of type 2 DM (T2DM) and a leading cause of acquired blindness in middle-aged individuals in many countries. Previous studies have identified associations of several gene polymorphisms with susceptibility to microvascular complications of DM in various worldwide populations. In our study, we aimed to test the hypothesis of the associations of single nucleotide polymorphisms (SNP) of the VEGF (−2549I/D), RAGE (−429T/C and −374T/A), TCF7L2 (rs7903146), and ITGA2 (BglII) genes with a predisposition to DR among T2DM patients in the Kazakhstan population. Materials and Methods: We conducted a case–control study comparing the genotype distribution and allele frequencies between groups of DR patients (N = 94), diabetic patients without DR (N = 94), and healthy controls (N = 51). Genotypes were identified using the PCR-RFLP method. Results: In all cases, the genotype distribution corresponded to the Hardy–Weinberg equilibrium. The groups of diabetic patients with and without DR did not significantly differ in the genotype distribution of the SNPs studied. Differences between both groups of diabetic patients and healthy controls in four out of five SNPs were also not significant. At the same time, both groups of diabetic patients differed significantly from healthy controls in genotype distribution (p = 0.042 and 0.005, respectively) and allele frequencies (p = 0.021 and 0.002, respectively) of the BglII polymorphism in the ITGA2 gene. After adjusting for multiple comparisons, the differences between the group of diabetic patients without DR and the control group remained significant (p_Bonf = 0.027 for genotypes and p_Bonf = 0.009 for alleles). The BglII− allele was associated with diabetes: OR = 1.81 [1.09–2.99] for DR patients, and OR = 2.24 [1.34–3.75] for diabetic patients without DR. The association was also observed in the subset of Kazakhs. Conclusions: This study shows that the BglII polymorphism in the ITGA2 gene can be associated with T2DM but not with DR. According to our data, the risk allele for diabetes is the wild BglII− allele, and not the minor BglII+, which is considered as risky for DR.