Background/Objectives: Autism spectrum disorder (ASD) has a wide-ranging impact on individuals’ quality of life and development, and there is a critical need for greater awareness, early intervention, and comprehensive support strategies to effectively address the unique needs of those affected by ASD. Recent studies highlight the gut microbiome’s potential role in modulating ASD symptoms via the gut–brain axis, but specific microbial biomarkers remain unclear. This study aims to investigate differences in gut microbiota composition between ASD patients and neurotypical controls in a novel approach, specifically assessing ratios of Firmicutes/Bacteroidetes (F/B), Actinobacteria/Proteobacteria (A/P), and Prevotella/Bacteroides (P/B) as potential biomarkers. Methods: We analyzed gut microbiome samples from 302 Bulgarian children and adolescents diagnosed with ASD (aged 2–19 years). Microbial ratios (F/B, A/P, and P/B) were calculated and compared against previously reported reference meta-analytic means from European neurotypical populations. The statistical significance of deviations was assessed using parametric (t-tests), non-parametric (Wilcoxon signed-rank tests), and proportion-based (binomial tests) methods. Effect sizes were quantified using Cohen’s d. Significant differences between ASD cases and neurotypical reference values were observed across several age groups. Results: Notably, children with ASD demonstrated significantly lower F/B and A/P ratios, with the youngest cohort (0–4 years) exhibiting the greatest differences. Deviations in the P/B ratio varied across age groups, with a significant elevation in the oldest group (≥10 years). Collectively, ASD cases consistently exhibited microbiota profiles indicative of dysbiosis. Conclusions: Our findings support gut microbiome dysbiosis as a potential biomarker for ASD, highlighting significantly altered bacterial ratios compared to neurotypical controls. These microbiome shifts could reflect early-life disruptions influencing neurodevelopment. Future studies should adopt longitudinal and mechanistic approaches to elucidate causal relationships and evaluate therapeutic microbiome modulation strategies.

We aim to investigate the role of the Herpesviridae family (HHV) in the onset and progression of prostate cancer (PCa) and to profile the local PCa immunological status. A total of 116 “tru-cut” biopsies (58 PCa and 58 benign prostatic hyperplasia [BPH]) and 49 formalin-fixed paraffin-embedded (FFPE) instances of PCa were analysed using real-time qPCR and histological examination. Infection with CMV, EBV, HHV6, and HHV7 was detected in 11.5% of the “tru-cut” biopsies (25.9% in BPH and 6.9% in the PCa group). In the formalin-fixed paraffin-embedded (FFPE) samples, infection was detected in 69.4% of the patients, with individual rates of EBV (47%), HHV6 (38%), HHV7 (41%), CMV (2.9%), HSV2 (2.9%), and VZV (5.8%). In the HHV-infected PCa cases, the histopathological landscape included intratumor lymphocyte infiltration with fibrosis and necrosis, periductal chronic inflammatory reaction and granulomatous lesions with foci of abscesses and necrosis, as well as inflammatory infiltration, chronic lymphadenitis, prostatic intraepithelial atrophy (PIA), and high-grade prostatic intraepithelial neoplasia (HGPIN). The majority of HHV-infected PCa patients were predominantly classified as grade G3/G4/G5 tumours, exhibiting perineural, perivascular, and lymphovascular invasion, seminal vesicle invasion, senile vesicle amyloidosis, and lymph node metastasis. Statistical analysis demonstrated a significant association between HHV infection and PCa (χ² ≈ 20.3, df = 1, p < 0.0001; Fisher’s exact test, p < 0.0001) with an odds ratio of 6.50 (95% CI: 2.80–15.12). These findings suggest that long-term HHV infection could contribute to a complicated and potentially altered immune PCa tumour environment due to inflammation. This may serve as a predictor of aggressive disease progression.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by wide clinical and biological heterogeneity, with a large proportion of ALS patients also exhibiting frontotemporal dementia (FTD) spectrum symptoms. This project aimed to characterize risk subtypes of the H1 haplotype within the MAPT (microtubule-associated protein tau) gene, according to their possible effect as a risk factor and as a modifying factor in relation to the age of disease onset. One hundred patients from Bulgaria with sporadic ALS were genotyped for the variants rs1467967, rs242557, rs1800547, rs3785883, rs2471738, and rs7521. Haploview 4.2 and SHEsisPlus were used to reconstruct haplotype frequencies using genotyping data from the 1000 Genomes project as controls. Genotype–phenotype correlation was investigated in the context of age of disease onset and risk of disease development. While the individual variants of the subtypes do not influence the age of onset of the disease, a correlation was found between the specific haplotype GGAGCA (H1b) and the risk of developing sALS, with results showing that individuals harboring this haplotype have a nearly two-fold increased risk of developing sALS compared to other H1 subtypes. The results from this study suggest that fine transcriptional regulation at the MAPT locus can influence the risk of ALS.

This study investigated the role of the CHGB P413L variant (rs742710) in sporadic amyotrophic lateral sclerosis (sALS) within the Bulgarian population. We analyzed 150 patients with sALS (85 male and 65 female) for the presence of this variant, its potential impact on disease susceptibility, and age of onset. Genotyping was performed using PCR amplification and direct Sanger sequencing. Statistical analyses included comparisons with control data from GnomAD v2.1.1, one-way ANOVA, and Kaplan–Meier survival analysis. Results revealed a higher frequency of the minor T allele in patients with sALS compared to all control groups and a statistically significant increase in carrier genotypes compared to non-Finnish Europeans (χ² = 15.4572, p = 0.000440). However, the impact on age of onset was less clear, with no statistically significant differences observed across genotypes or between carriers and non-carriers of the T allele. Kaplan–Meier analysis suggested a potential 2.5-year-earlier onset in T allele carriers, but the small sample size of carriers limits the reliability of this finding. Our study provides evidence for an association between the CHGB P413L variant and sALS susceptibility in the Bulgarian population, while its effect on age of onset remains uncertain, highlighting the need for further research in larger, diverse cohorts.

This study aims to identify laboratory and genetic markers important for COVID-19 severity to improve patient assessment and treatment. COVID-19 patients were divided into two groups based on disease severity. Clinical, laboratory (complete blood count, complete biochemical parameters - lactate dehydrogenase (LDH), serum ferritin), and genetic markers (OAS1 rs4767027) were analyzed. A total of 61 COVID-19 patients and 48 negative controls were investigated. Group I showed more often lymphopenia – 3.16 (1.39–3.89) vs 5.61(4.21–7.98), p-0.027 and thrombocytopenia – 165 (75–256) vs 212 (198–349), p-0.031, higher LDH (621 ± 218 U/L vs 312 ± 110 U/L), p-0.014. OAS1 rs4767027 genotype and allele frequencies did not differ significantly from worldwide population frequencies. Lymphopenia and thrombocytopenia are likely associated with immune inflammation and COVID-19 severity. While increased OAS1 transcript levels are correlated with reduced risk of infection, they can contribute to NLRP3 inflammasome activation once the infection has been established.