Polymorphisms of milk protein genes have been proposed as candidate markers for dairy production traits in cattle. In the present study, a polymorphism was detected in the 5′-flanking (promoter) region of the bovine alpha-lactalbumin (LALBA) gene, a T/C transition located at nucleotide −1,001 relative to the transcription start site g.-1001T > C (NC_037332.1:g.31183170T > C), which is recognizable with PstI restriction endonuclease. In silico analyses showed that this mutation created novel retinoid X receptor alpha and vitamin D receptor transcription factor binding sites. Real-time PCR found that cows with different genetic variants of the promoter demonstrated different levels of expression of LALBA mRNA in milk somatic cells (MSCs). The TT genotype cows demonstrated low expression, whereas those with CT demonstrated much higher expression (P < 0.05). ELISA analysis found milk LALBA protein levels also differed between the TT and CT cows (P < 0.05) and that these levels were not correlated with the mRNA abundance in MSC. Association analysis found that the g.-1001T > C polymorphism in the promoter region of the LALBA gene influenced milk production traits in Polish Holstein-Friesian cows. High daily milk yield and dry matter yield, and high lactose yield and concentration were associated with the TT genotype. The TT genotype cows also had a lower number of somatic cells in the milk, considered as an indicator of udder health status. Therefore, the TT genotype could be more desirable from the breeder’s perspective.

In this study, novel single nucleotide polymorphisms (SNPs) were found in the 5′-regulatory regions (promoters) of the bovine glucose transporter (GT) genes SLC2A12 and SLC5A1. These polymorphisms were shown to associate with certain milk production traits in HF cows, including milk yield, milk composition, and somatic cell count. It was shown that the SNP g.-671C > G (NC_037336.1: g.72224078C > G) in the SLC2A12 gene could be an effective marker of cattle production traits and that genotypes CC and CG are associated with the best productivity. The polymorphisms found in the SLC5A1 gene promoter also influenced milk production traits in HF cows, albeit to a lesser extent, and we propose that these polymorphisms could be useful as genetic markers for milk production traits in marker-assisted selection (MAS); however, this must be confirmed on larger populations of cattle. In addition, the presence of polymorphisms within promoter regions appears to affect the expression of GT genes in the cow mammary gland and modify transcription factor (TF) binding capacity.

Background: Phenylketonuria (PKU) is a metabolic disorder that necessitates dietary restrictions, potentially impacting the composition of gut and oral microbiota. This study aimed to compare the microbiota composition between children with PKU and healthy controls. Methods: Using 16S rRNA gene sequencing, we analysed microbial communities at six phylogenetic levels. Results: Our findings revealed significant differences in the gut microbiota: Euryarchaeota was more abundant in controls (p = 0.01), while Bacilli and Lactobacillales were higher in PKU children (p = 0.019). Methanobacteriales were significantly elevated in controls (p = 0.01). At the genus and species levels, PKU children had higher Streptococcus and Eubacterium dolichum (p = 0.019, p = 0.015), whereas controls had more Barnesiella, Coprococcus, and Faecalibacterium prausnitzii (p = 0.014, p = 0.019, p = 0.014). In the oral microbiota, control children exhibited significantly higher Bacteroidetes (p = 0.032), while PKU children had increased Bacilli and Betaproteobacteria (p = 0.0079, p = 0.016). Streptococcus and Neisseria were more prevalent in PKU (p = 0.0079, p = 0.016). Conclusions: These results suggest that PKU and its dietary management significantly alter the gut and oral microbiota composition. Understanding these microbial shifts could have implications for managing PKU and improving patient outcomes.

Measuring gene expression is a commonly used method to monitor the reaction of cells and tissues to changing nutritional or physiological conditions. Selection of appropriate reference genes is a crucial point in gene expression experiments using real-time PCR techniques. Expression of the "ideal" reference gene should not be affected by the experimental treatments or physiological state of the tissue, organ, or the whole organism. Many programs are available from which to choose the most stable reference gene. In this study, 4 algorithms--ΔCt, BestKeeper, NormFinder, and geNorm--were used to assess the expression stability of 5 candidate reference genes: β-actin (ACTB), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein S9 (RPS9), ribosomal protein L32 (RPL32), and TATA-box-binding protein (TBP), for use in an experiment aimed at measuring gene expression in the liver of cows fed glucogenic supplements in the transition from pregnancy to lactation. The results demonstrated that RPS9 and RPL32 were the most stably expressed in the liver under the conditions of the present experiment; the least stably expressed was ACTB.

Background: Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder characterized by reproductive and metabolic abnormality disorders. Dietary factors influence the body composition and hydration status, which may exacerbate PCOS symptoms. The aim of this study was to assess the associations between the habitual nutrient intake and bioelectrical impedance analysis parameters in Polish women with PCOS and healthy controls, in order to identify potential nutritional targets for a non-pharmacological intervention. Methods: This study involved 50 women aged 18–45 years (25 with PCOS and 25 healthy). Participants kept 7-day food diaries and their body composition was assessed using the SECA mBCA 515 analyzer. The nutrient intake was compared with EFSA recommendations. Results: Women with PCOS had a higher body weight, waist circumference and body mass index, visceral adipose tissue, and fat mass index, despite no difference in their total energy intake. They consumed more omega-3 fatty acids (EPA + DHA) than the control group. Vitamin D deficiency and irregular supplementation were common in both groups. Body composition parameters such as the phase angle and ECW/TBW ratio correlated with the diet quality—especially with protein; fiber; and vitamin B2, B12, and folate levels. Conclusions: The obtained results showed significant differences in body compositions and the presence of a relationship between the nutrient intake and bioimpedance parameters in women with PCOS. These results emphasize the importance of a comprehensive nutritional and body composition assessment in planning dietary interventions in this group of patients.

Background: Phenylketonuria (PKU) is a metabolic disorder managed through a strict, lifelong low-phenylalanine diet, which may influence gut microbiome dynamics. While gut bacterial alterations in PKU are increasingly investigated, the fungal community (mycobiome) remains largely unexplored. This study compared gut mycobiome composition and dietary profiles of paediatric PKU patients and healthy controls, stratified by age (<10 and 10–18 years). Methods: Stool samples from 20 children (10 PKU, 10 controls) were analysed using ITS1/ITS2 amplicon sequencing. Nutritional status was assessed using Body Mass Index percentiles (Polish standards), and nutrient intake was evaluated from three-day dietary records compared to national reference values. Correlations between fungal taxa and dietary factors were explored. Results: Although alpha diversity did not differ significantly, beta diversity and LEfSe analyses revealed distinct fungal profiles between PKU patients and controls, indicating a trend toward group separation (PERMANOVA: F = 1.54646, p = 0.09; ANOVA: p = 0.0609). PKU patients showed increased Eurotiales (p = 0.029), Aspergillaceae (p = 0.029), and Penicillium (p = 0.11) and decreased Physalacriaceae (0% vs. 5.84% in controls) and Malassezia (p = 0.13). Spearman’s analysis showed significant correlations between Geotrichum and intake of protein (ρ = 0.55, p = 0.0127) and phenylalanine (ρ = 0.70, p = 0.0005). Conclusions: Dietary treatment in PKU is associated with age-dependent shifts in the gut mycobiome, notably increasing the abundance of taxa such as Eurotiales, Aspergillaceae, and Penicillium, involved in carbohydrate/lipid metabolism and mucosal inflammation. These findings highlight the potential of gut fungi as nutritional and clinical biomarkers in PKU.