TaqI Polymorphisms Research Articles

ApaI Polymorphism in the Vitamin D Receptor Gene Decreases the Risk of Perianal Fistulas in Crohn’s Disease

Background: Vitamin D, through the activation of its receptor (VDR), plays an immunomodulatory role in the gastrointestinal tract. Single-nucleotide polymorphisms (SNPs) in the VDR gene have been associated with Crohn’s disease (CD) risk, and patients carrying the TaqI polymorphism in this gene run a higher risk of developing a penetrating behavior. Aims: We analyzed the association of BsmI, ApaI, TaqI, and FokI SNPs in the VDR gene with the clinical characteristics of CD. Methods: Four polymorphisms identified in the VDR gene (BsmI, FokI, ApaI, and TaqI) were genotyped in blood samples from CD patients (n = 115) by using PCR-RFLP. The disease’s location and behavior and the presence of perianal fistulas were collected from each patient. Intestinal fibroblasts from ileal resections of CD patients (n = 10) were genotyped, and the expression of fibrotic and inflammatory markers was analyzed by RT-PCR. Results: The data reveal no association between any of the polymorphisms and CD risk. A strong linkage disequilibrium was detected between TaqI and both ApaI and BsmI, which in turn were strongly associated. Homozygosis or heterozygosis for the a allele of the ApaI SNP or b allele of the BsmI SNP was significantly associated with a lower risk of a penetrating behavior, while the aa genotype was associated with a lower risk of perianal fistulas. Fibroblasts carrying the aa genotype expressed lower levels of fibrotic and inflammatory markers. Conclusion: The aa genotype of the ApaI SNP in the VDR gene is associated with a lower risk of perianal fistulas in CD and a reduced expression of fibrotic and inflammatory markers in intestinal fibroblasts.

Evaluation relationship between VDR gene and clinical and inflammatory factors in patients with RRMS.

Adipocyte levels including leptin and FABS-4 levels, adiponectin, obesity, and vitamin D can be related to the occurrence and exacerbation of MS disease. This research aimed at determining the relationship between VDR gene changes and clinical and inflammatory factors in patients with relapsing-remitting multiple sclerosis (RRMS). This case/control study was conducted based on the ethical principles of Helsinki. RRMS disease was confirmed based on history, clinical signs, radiological signs, and neurologist's diagnosis. The research population consisted of healthy people and patients with RRMS referring to Hazrat Rasool Akram Hospital between 2021 and 2023 who met the criteria for entering the research. FokI polymorphism is associated with a substantial increase in risk, with an odds ratio of 7.28, for those with the FF genotype who have RRMS compared to healthy individuals (OR=7.28: 95% CI; 1.86, 28.41). The presence of FokI polymorphism significantly raises the likelihood of developing RRMS in persons with the FF genotype compared to healthy individuals, with an odds ratio of 28.7. RRMS patients with genotypes did not exhibit a significant increase in risk compared to controls for FokI, ApaI, TaqI, and BsmI polymorphisms. None of the studied polymorphisms revealed a significant risk in obese patients with different genotypes compared to the obese people. Further research, including more cases, is needed to avoid results that could be inflated by small samples or low frequencies of minor alleles.

Association of Vitamin D receptor gene polymorphisms (FokI, ApaI, TaqI), metabolic features and susceptibility to polycystic ovary syndrome: a preliminary single center case-control study

Research questionAre the combined genotypes and haplotypes of VDR gene polymorphisms (FokI, ApaI, TaqI) associated with PCOS susceptibility and metabolic features of the disease? DesignWe performed a case-control study, including 46 women with PCOS and 48 controls. Genotypes of VDR genes were determined using the PCR-RFLP (restriction fragment length polymorphism) method. In all women, the waist circumference, parameters of lipid and glucose metabolism were evaluated. ResultsPCOS group presented higher waist circumference and visceral adiposity index (VAI) levels compared to controls. Total cholesterol, LDL-C and triglycerides had higher values in PCOS women. VDR-FokI C/C (F/F) genotype had significantly higher odds of PCOS (adjusted OR = 6.27, 95% CI: 1.53-25.65). VDR-Apal was associated with susceptibility to PCOS in the dominant model, the variant genotype (A/C-A/A) (A/a- a/a) had higher odds of PCOS than the wild genotype C/C (A/A) (adjusted OR = 3.15, 95% CI: 1.07-9.32). Haplotype analysis revealed that T-C- T (f-A-T) haplotype was statistically associated with lower odds of PCOS (adjusted OR = 0.10, 95% CI: 0.01-0.95). PCOS women with VDR-Fokl T/T (f/f) genotype had lower fasting glucose and higher VAI levels compared to C/T (Ff) or C/C (F/F) genotype. ConclusionThe present findings suggest the association between FokI and ApaI polymorphisms and PCOS susceptibility. Moreover, T/T (f/f) genotype of VDR-FokI could be a marker of decreased fasting glucose in PCOS. TaqI polymorphism did not reveal a relationship with PCOS susceptibility in our study population.

Association between vitamin D receptor gene polymorphisms and susceptibility to tuberculosis: a systematic review and meta-analysis.

Tuberculosis (TB) is the leading cause of mortality worldwide. Previous studies have reported that TB susceptibility can be caused by vitamin D deficiency, which is affected by polymorphisms in the vitamin D receptor (VDR) gene. However, these results have been inconsistent. Therefore, we performed a meta-analysis to investigate the association between VDR polymorphisms and TB susceptibility. We systematically searched for relevant literature in PubMed, Embase, and Medline databases through December 31st, 2022. Inclusion and exclusion criteria were made to ensure that HIV-negative population is the targeted subjects. The pooled odds ratio (OR) and 95% confidence interval (CI) were then used to assess the strength of the association, and the quality of the included articles was evaluated using the Newcastle-Ottawa Scale. Potential sources of heterogeneity were evaluated based on subgroup and meta-regression analyses. In our meta-analysis, we found that the FokI polymorphism in the VDR gene was associated with increased TB susceptibility in the allele and recessive genotype models (OR f vs. F = 1.235, 95%CI: 1.035-1.475; OR ff vs. Ff + FF = 1.317, 95%CI: 1.005-1.727. Further subgroup analysis based on ethnicity demonstrated the association with the risk of TB in all genotype models of the FokI polymorphism for Han population. Meta-regression analysis also indicated that ethnicity could be a potential source of heterogeneity in the FokI and BsmI polymorphisms in the VDR gene. However, publication year was another source of heterogeneity for the TaqI polymorphism. In summary, the FokI polymorphism in the VDR gene was found to increase the risk of TB in the HIV-negative population, both overall and in Asian populations. The findings presented in this paper could provide clues for preventing TB from the perspective of vitamin D supplementation, which is a controversial topic in the field of medicine and health.

Gene Variants of Vitamin D Receptor (TaqI T > C (rs731236) and BsmI G > A (rs1544410) in Urolithiasis

Background: Urolithiasis is the most prevalent uronephrologic disorder caused by genetic, environmental factors, and metabolic defects. Objectives: The present study aimed to find a possible association between the vitamin D receptor (VDR) TaqI and the BsmI gene polymorphisms in relation to the serum levels of calcium (Ca) and vitamin D and the risk of urolithiasis. Methods: This case-control study was conducted on 68 children with urolithiasis and 67 healthy controls for the VDR gene polymorphisms using the polymerase chain reaction-restriction length polymorphism method. Results: The frequency of TaqI C allele was 36% in patients compared to 32.1% in controls (P = 0.49). A significantly higher frequency of the TaqI CC genotype was found among patients in the age group > 5 to 10 years. No significant difference was detected in the frequency of the BsmI A allele between patients (41.9%) and controls (42.5%, P = 0.91). However, a significantly lower frequency of the BsmI AA genotype was detected compared to those patients with Ca levels of > 10.8 mg/dL among patients with Ca levels of ≤ 10.8 mg/dL. Conclusions: Based on the results, a lack of an association between the VDR TaqI and BsmI polymorphisms with the risk of urolithiasis among children from Western Iran. However, a higher frequency of the TaqI CC genotype was found in the age group > 5 to 10 years. In addition, lower levels of Ca in patients were related to a significantly lower frequency of the BsmI AA genotype. The VDR gene BsmI polymorphism might affect the calcium level and the calcium metabolism in urolithiasis.

TaqI polymorphism of VDR gene in colorectal cancer and Crohn’s disease patients

To study the relation of TaqI polymorphism of VDR gene with age, sex and the disease phenotype in patients with colorectal cancer (CRC) and Crohn’s disease (CD) from western regions of Ukraine. Fifty six patients with CRC, 46 patients with CD and 65 control individuals were included in this research. Assessment of TaqI polymorphism was performed using PCR-RFLP method. The genotype-phenotype association for this polymorphism was analyzed. The frequency of tt genotype in patients with CRC is 0.107 and among the control group is 0.138, OR (95% CI 0.248-2.246). The ratio of genotypes TT:Tt:tt in patients with CRC and in control was 37.5%:51.8%:10.7% and 44.6%:41.6%:13.8%. In men with Tt genotype the average age of CRC onset was 57.6 ± 3.6 years, in women with TT genotypethe mean age of the disease onset was 54.5 ± 4.5 years. The frequency of tt genotype in the patients with CD is 0.217 and among the control group is 0.138, OR (95% CI 0.640–4.666). The Tt genotype was detected in a half of patients with CD and TT genotype was found more frequently in control.The ratio of genotypes in men and women with CD was 38.0%:38.0%:24.0% and 20.0%:60.0%:20.0%. Among patients with CD, who underwent surgery, 33.3% individuals were carriers of tt genotype. It was confirmed no statistically significant difference in the allele frequencies and genotype distributions of Taq1 mutation in patients with CRC and CD in comparison to control group. The ratio of men and women with Tt genotype by groups of B1-B3 forms of CD behaviour according to the Montreal classification is differs, in particular, women with Tt genotype are four times more likely to have the B1 form. A study of Taq1 mutation might contribute to the identification of the groups that are at the greatest risk of severe form of CD.

Vitamin D receptor gene polymorphisms, bioavailable 25-hydroxyvitamin D, and hepatocellular carcinoma survival.

Little is known about the role of vitamin D receptor polymorphisms and their interaction with vitamin D status in hepatocellular carcinoma (HCC) prognosis. We evaluated the association of TaqI, BsmI, Cdx-2, and ApaI polymorphisms, individually and in combination, with liver cancer-specific (LCSS) and overall survival (OS) among 967 patients with newly diagnosed HCC. Subsequently, we examined whether these polymorphisms modified the association between serum bioavailable 25-hydroxyvitamin D (25OHD) concentrations and survival. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). During a median follow-up of 1017 days, 393 deaths occurred, with 360 attributed to HCC. Having TaqI G allele (HRper allele = 1.30, 95% CI = 1.08 to 1.57) or BsmI T allele (HRper allele = 1.41, 95% CI = 1.01 to 1.99) was associated with worse LCSS. Carrying increasing numbers of protective alleles was associated with superior LCSS (HR6-8 vs 0-3 = 0.52, 95% CI = 0.34 to 0.80). The inverse association of bioavailable 25OHD with LCSS was statistically significant only in patients with TaqI AA (HRQuartile 4 vs Quartile 1 = 0.63, 95% CI = 0.44 to 0.92), BsmI CC (HRQuartile 4 vs Quartile 1 = 0.62, 95% CI = 0.44 to 0.88), and 6 to 8 protective alleles (HRQuartile 4 vs Quartile 1 = 0.45, 95% CI = 0.23 to 0.87). Similar associations were observed for OS. Patients carrying wild-type TaqI, BsmI, or more protective alleles had improved survival and might benefit from optimizing bioavailable 25OHD status.

Association of vitamin D receptor genetic polymorphisms with the risk of infertility: a systematic review and meta-analysis

BackgroundThe causes of infertility have remained an important challenge. The relationship between VDR gene polymorphisms and infertility has been reported, with controversial findings.Objective and rationaleWe aimed to determine this relationship by conducting a systematic review and meta-analysis.Search methodsThe study was started with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) declaration and the final draft was registered as a protocol in PROSPERO (ID: CRD42023416535). The international electronic databases including PubMed (Medline), Scopus, Web of Sciences, and Cumulative Index to Nursing and Allied Health Literature (CINHAL) were searched until January 30, 2023, by using appropriate keywords. The quality of the final studies was assessed using the NOS Checklist for case–control studies. The odds ratios (ORs) for each of the genetic models were pooled, and a subgroup analysis based on geographical region and types of infertility was carried out by the MetaGenyo online tool.OutcomesCase–control studies including 18 and 2 studies about infertility in women and men, respectively, and 4 miscarriage studies were entered into the meta-analysis. The VDR gene TaqI polymorphism was associated with infertility susceptibility in women in the allele contrast [OR = 1.2065, 95% CI (1.0846–1.3421); P = 0.0005], Recessive model [OR = 1.3836, 95% CI (1.1197–1.7096); P = 0.002], Dominant model [OR = 1.2146, 95% CI (0.0484–1.4072); P = 0.009], Homozygote [OR = 1.4596, 95% CI (1.1627–1.8325); P = 0.001], and TT vs. Tt [OR = 1.2853, 95% CI (1.0249–1.6117); P = 0.029. ApaI and FokI gene polymorphisms were found to be significantly protective SNPs against women and men infertility in the Dominant model [OR = 0.8379, 95% CI (0.7039- 0.9975); P = 0.046] and Recessive model [OR = 0.421, 95% CI (0.1821–0.9767); P = 0.043], respectively. Sub-group meta-analysis showed a protection association of ApaI in dominant [OR = 0.7738, 95% CI = 0.6249–0.9580; P = 0.018] and AA vs. aa [OR = 0.7404, 95 CI% (0.5860–0.9353) P = 0.011725] models in PCOS subgroup, however, a negative association with idiopathic infertility was found in AA vs. Aa [OR = 1.7063, 95% CI (1.1039–2.6375); P = 0.016187] and Aa vs. aa [OR = 0.6069, 95% CI (0.3761–0.9792); P = 0.040754]. TaqI SNP was significantly associated with infertility in the African population and BsmI was associated with the disease mostly in the Asian population.ConclusionThis meta-analysis showed that the TaqI polymorphism may be linked to women’s infertility susceptibility. However, ApaI and FokI might be the protective SNPs against infertility in Women and men, respectively.

Association of TaqI (rs731236) Polymorphism of Vitamin D Receptor Gene with Lumbar Degenerative Disc Disease

Lumbar degenerative disc disease (LDDD) significantly contributes to low back pain, with a complicated etiology involving genetic and environmental facts. The aim of study was to investigate the association between the TaqI (rs731236) polymorphism of the vitamin D receptor (VDR) gene with LDDD. In total, 248 patients with symptomatic LDDD and 146 control subjects were examined. The evaluation of clinical features of patients with LDDD comprised radiodiagnostic magnetic resonance imaging, neurologic examinations, pain scores including the visual analog scale (VAS), and disability investigation with Oswestry Disability Index (ODI). Genotyping of the VDR gene polymorphism was conducted using polymerase chain reaction-based methods. Individuals of the LDDD group who were VDR TaqI AA genotype carriers were significantly greater than the other group (P= 0.014), whereas those with GG genotype were significantly lower (P= 0.028) in the patient group. In addition, VAS and ODI scores were significantly lower in the GG genotype carrier group, whereas AA genotype carriers had the greatest scores (P= 0.004). Carrying the G allele decreased the risk of LDDD 1.7 times (P= 0.014) and carrying the A allele enhanced the risk 1.8 times (P= 0.028). Moreover, G-allele carriers had significantly lower VAS (P= 0.002) and ODI scores (P < 0.0001). VDR TaqI (rs731236) GG genotype and G allele have protective potential, whereas the AA genotype and A allele are risk factors for LDDD. The findings reveal a statistically significant association of the TaqI (rs731236) polymorphism of VDR gene polymorphism with LDDD. This result highlights the potential role of genetic factors in developing LDDD and suggests avenues for future research in genetic screening and personalized treatment strategies.

Associations between the VDR Gene rs731236 (TaqI) Polymorphism and Bone Mineral Density in Postmenopausal Women from the RAC-OST-POL.

Postmenopausal osteoporosis is not only related to hormonal factors but is also associated with environmental and genetic factors. One of the latter is the polymorphism of vitamin D receptor (VDR). The aim of the reported study was to comprehensively analyze the VDR gene polymorphic variants rs731236 (TaqI), rs1544410 (BsmI) and rs7975232 (ApaI) in the Polish population of postmenopausal women. The study group consisted of 611 women after menopause (their median age was 65.82 ± 6.29 years). Each of them underwent bone densitometry (DXA) of the non-dominant femoral neck and total hip with a biochemical analysis of vitamin D3 serum concentration and genotyping of the above-mentioned single nucleotide polymorphisms (SNPs); the obtained results were analyzed in the aspect of waist circumference (WC), body mass index (BMI) and past medical history. The genotype prevalence rates of all SNPs were compatible with Hardy-Weinberg equilibrium (p > 0.050). Out of the studied polymorphisms, only rs731236 genotype variants affected DXA, with AG heterozygotes showing the worst bone parameters. Neither patient age nor vitamin D3 concentration, BMI, WC or comorbidities was associated with rs731236 genotype. Out of the polymorphisms studied, only rs731236 genotypes differed among the DXA results, while the AG heterozygotes were characterized by the lowest median bone mineral density.

The Association of Vitamin D Receptor Polymorphisms with COVID-19 Severity.

Association studies of vitamin D receptor (VDR) polymorphisms with COVID-19 severity have produced inconsistent results in different populations. Herein we examined VDR gene polymorphisms in a Caucasian Greek cohort of COVID-19 patients. This was a case-control study in a tertiary university hospital in Greece including 137 COVID-19 patients with varying disease severities and 72 healthy individuals. In total 209 individuals were genotyped for the FokI (rs10735810), ApaI (rs7975232), TaqI (rs731236) and BsmI (rs1544410) single-nucleotide polymorphisms (SNP) of the VDR gene by polymerase chain reaction and restriction fragment length polymorphism analysis (PCR-RFLPs). Statistical analyses were performed to determine the association between genotype and disease severity, adjusting for various confounding factors. Genotype distribution of the studied VDR SNPs in the control group was in Hardy-Weinberg equilibrium. The TaqI variant was differentially distributed between controls and COVID-19 patients according to the additive model (p = 0.009), and the CC genotype was significantly associated with an increased risk for severe COVID-19 according to the recessive model [OR: 2.52, 95%CI:1.2-5.29, p = 0.01]. Multivariate analysis demonstrated a robust association of COVID-19 severity and TaqI polymorphism in the recessive model even after adjusting for multiple confounders, including age, sex and CRP levels [Adj.OR:3.23, 95%CI:1.17-8.86, p = 0.023]. The distribution of FokI, ApaI and BsmI genotypes was similar between COVID-19 patients and controls. The CC genotype of TaqI polymorphism is significantly associated with an increased risk for severe COVID-19 independently of age, sex or degree of inflammation.

Prevalence of Vitamin D Receptor Genes Polymorphisms in People with Pulmonary Tuberculosis: A Systematic Review and Meta-Analysis.

Polymorphisms in the vitamin D receptor (VDR) play an effective role in the susceptibility of pulmonary tuberculosis (TB). Given the importance of this polymorphism and its association with pulmonary TB, this study aimed to investigate the prevalence of VDR polymorphisms in people with pulmonary TB. The search process was performed from 2009 to 2023 according to PRISMA (Preferred reporting items for systematic reviews and meta-analyses). The strengthening of the reporting of observational studies in epidemiology (STROBE) checklist was used to qualify the articles. The data was entered into STATA version 14 software, then the fixed effects model and the random effects model, effect size (ES), and Q test (P < 0.10) were used for data analysis at a confidence interval level (CI) of 95%. Two-sided statistical tests were considered with α=0.05. In this research, 28 articles were analyzed. Polymorphisms showed a significant relationship with susceptibility to pulmonary TB (P = 0.000), and significant heterogeneity (P = 0.000) was seen between polymorphisms. FokI (95% CI: 0.39-0.46, P = 0.000, ES = 43%), ApaI (95% CI: 0.31-0.48, P = 0.000, ES = 39%) and BsmI (95% CI: 0.24-0.50, P = 0.000, ES = 37%) showed the most frequent gene polymorphisms after TaqI (95% CI: 0.34-0.77, P = 0.000, ES = 56%). ApaI, BsmI, FokI, and TaqI polymorphisms were found in patients suffering from pulmonary TB. Polymorphisms related to the TaqI gene were the most frequent. Controlling and prescribing vitamin D may be needed in these patients.

Vitamin D Receptor Polymorphisms in a Spanish Cohort of Parkinson's Disease Patients.

Background: Vitamin D receptor (VDR) is a nuclear hormone receptor widely expressed in the substantia nigra. Its association with an increased risk of Parkinson's disease (PD) is based on vitamin D deficiency and/or different polymorphisms in its gene receptor. This fact has been demonstrated by several case-control studies. Materials and Methods: Consequently, we investigated the association between VDR ApaI, BsmI, FokI, and TaqI gene polymorphisms and PD in a Spanish cohort that included 54 cases and 17 healthy controls. The detection of single nucleotide polymorphisms (SNPs) was performed using a polymerase chain reaction-restriction fragment length polymorphism. Results: Our data indicate that the SNPs were not associated with the age of onset of PD, nor with the occurrence of motor symptoms. However, only BsmI polymorphism was significantly associated with PD in this Spanish cohort. In fact, BsmI genotype was five times higher among PD patients than among controls, and the A allele was considered as a genetic risk for PD. Additionally, the combination of FokI and BsmI polymorphisms was significantly associated with PD and could represent a risk factor. Conclusion: We conclude that ApaI, TaqI, and FokI polymorphisms were not associated with PD, but BsmI could be a risk factor for PD in this randomized population.

Assessment of vitamin D status and vitamin D receptor polymorphism in Egyptian children with Type 1 diabetes

BackgroundThe endocrine system of vitamin D regulates about 3 % of the human genome. Vitamin D exerts its actions via a nuclear vitamin D receptor (VDR) which in turn regulates insulin secretion from the pancreas. VDR gene polymorphisms could have an impact on how autoimmune illnesses like Type 1 diabetes mellitus (T1DM) develop. We aimed to explore the relation between T1DM and VDR gene polymorphisms in Egyptian diabetic children and their siblings. MethodsEnzyme-linked immunosorbent assay was used to quantify 25(OH) vitamin D in the study, which had 179 participants (group 1 = 85 diabetic children, group 2 = 57 siblings of the patients, group 3 = 37 healthy controls). Real-time polymerase chain reaction (RT-PCR) was used to analyze the genotyping of the VDR gene polymorphisms Apa-I (rs7975232), Fok-I (rs2228570), Taq-I (rs731236) and Bsm-I (rs1544410). ResultsThe mean serum 25(OH) vitamin D levels was significantly lower in T1DM patients (14.99 ± 9.24 ng/mL) and siblings (16.31 ± 7.96 ng/mL) compared to the controls (19.48 ± 7.42 ng/mL) (p = 0.031). The genotypes distribution of VDR Fok-I (rs2228570) and Bsm-I (rs1544410) polymorphisms showed a significant difference between patients, siblings and controls as P = 0.001 and 0.026 respectively, while the VDR ApaI and TaqI polymorphisms did not. FokI-A allele frequency was significantly lower in T1DM patients and siblings than in controls (p < 0.001). FokI-AA genotype had a statistical significant higher vitamin D levels than other genotypes with p value of 0.024. ConclusionOur study found that T1DM children had lower vitamin D levels, and VDR FokI and BsmI gene polymorphisms were linked to T1DM in Egyptian children. Determining the relationship between vitamin D levels and VDR polymorphisms, particularly the FokI and other genetic analyses may aid in the early diagnosis of T1DM in children.

VDR gene TaqI (rs731236) polymorphism affects gut microbiota diversity and composition in a Caucasian population.

The VDR gene is identified as a crucial host factor, influencing the gut microbiota. The current research focuses on an observational study that compares gut microbiota composition among individuals with different VDR gene TaqI polymorphisms in a Caucasian Spanish population. This study aims to elucidate the interplay between genetic variations in the VDR gene and the gut microbial composition. 87 healthy participants (57 men, 30 women), aged 18 to 48 years, were examined. Anthropometric measures, body composition, and dietary habits were assessed. VDR gene polymorphism TaqI rs731236 was determined using TaqMan assays. The V3 and V4 regions of the 16S rRNA gene were sequenced to study bacterial composition, which was analyzed using QIIME2, DADA2 plugin, and PICRUSt2. Statistical analyses included tests for normal distribution, alpha/beta diversity, ADONIS, LEfSe, and DESeq2, with established significance thresholds. No significant differences in body composition or dietary habits were observed based on VDR genotypes. Dietary intake analysis revealed no variations in energy, macronutrients, or fiber among the different VDR genotypes. Fecal microbiota analysis indicated significant differences in alpha diversity as measured by Faith's Phylogenetic Diversity index. Differential abundance analysis identified taxonomic disparities, notably in the genera Parabacteroides and Butyricimonas. Overall, this study suggests potential associations between genetic variations in the VDR gene and the composition and function of gut microbiota.

Vitamin D Deficiency and Receptor Polymorphisms as Risk Factors for COVID-19

Background: Early immune responses to COVID-19 can help eliminate the virus; therefore, strategies to improve the immune system have become important in disease prevention. Vitamin D plays a crucial role in the immune response to SARS-CoV-2 by increasing the expression of the vitamin D receptor. Objectives: This study investigated the impact of vitamin D deficiency, Fok 1, and Taq 1 Vitamin D Receptor (VDR) gene polymorphisms and comorbidities on the susceptibility to COVID-19. Methods: Fok1 and Taq1 polymorphisms were analyzed using the RT-PCR method, and vitamin D levels were measured using the chemiluminescence method. A total of 200 patients, 100 with COVID-19 and 100 without, provided blood samples for analysis. Results: The COVID-19 positive group had a significantly lower mean vitamin D level of 16.2 ± 11.3 ng/mL compared to the COVID-19 negative control group, 26.7 ± 15.9 ng/mL (P &lt; 0.001). Individuals with a vitamin D level below 18.4 ng/mL had a 2.448 times higher risk of COVID-19 positivity (P &lt; 0.001). There was no significant difference in the Fok1 and Taq1 gene polymorphisms between the two groups. (P = 0.548 and P = 0.098). The COVID-19 positive group had a significantly higher number of comorbid diseases with 40 (40%) compared to the negative group with 10 (10%) participants (P &lt; 0.001). Conclusions: Levels of vitamin D above the cut-off value of 18.4 ng/mL were found to protect against COVID-19, while the presence of comorbid diseases was identified as a risk factor. However, no association was observed between the Fok1 and Taq1 polymorphisms and susceptibility to COVID-19.

Exploring the Influence of VDR Genetic Variants TaqI, ApaI, and FokI on COVID-19 Severity and Long-COVID-19 Symptoms.

There is increasing evidence regarding the importance of vitamin D in the prognosis of coronavirus disease 2019 (COVID-19). Genetic variants in the vitamin D receptor (VDR) gene affect the response to vitamin D and have been linked to various diseases. This study investigated the associations of the major VDR genetic variants ApaI, FokI, and TaqI with the severity and long post-infection symptoms of COVID-19. In total, 100 Jordanian patients with confirmed COVID-19 were genotyped for the VDR ApaI, FokI, and TaqI variants using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. COVID-19 severity, the most commonly reported long-COVID-19 symptoms that lasted for >4 weeks from the onset of infection, and other variables were analyzed according to VDR genetic variants. In this study, ApaI and FokI polymorphisms showed no significant associations with COVID-19 severity (p > 0.05). However, a significant association was detected between the TaqI polymorphism and the severity of symptoms after infection with the SARS-CoV-2 virus (p = 0.04). The wild-type TaqI genotype was typically present in patients with mild illness, whereas the heterozygous TaqI genotype was present in asymptomatic patients. With regard to long-COVID-19 symptoms, the VDR heterozygous ApaI and wild-type TaqI genotypes were significantly associated with persistent fatigue and muscle pain after COVID-19 (p ˂ 0.05). Most carriers of the heterozygous ApaI genotype and carriers of the wild-type TaqI genotype reported experiencing fatigue and muscle pain that lasted for more than 1 month after the onset of COVID-19. Furthermore, the TaqI genotype was associated with persistent shortness of breath after COVID-19 (p = 0.003). Shortness of breath was more common among individuals with homozygous TaqI genotype than among individuals with the wild-type or heterozygous TaqI genotype. VDR TaqI is a possible genetic variant related to both COVID-19 severity and long-COVID-19 symptoms among Jordanian individuals. The associations between VDR TaqI polymorphisms and long-COVID-19 symptoms should be investigated in larger and more diverse ethnic populations.

Genetic association between vitamin D receptor gene and Saudi patients confirmed with Familial Hypercholesterolemia.

Familial Hypercholesterolemia (FH) is a common condition caused by inherited genetic abnormalities. Inadequate clearance of the circulating low-density lipoproteins (LDL) is the primary cause of the excessive concentrations of LDL seen in FH patients. The relation with vitamin D deficiency and vitamin D receptor (VDR) gene is well documented in the Saudi Arabia. The aim of this study was to investigate the role of molecular analysis studied between FH patients and fours polymorphisms associated with VDR gene in Saudi Population. In this case-control study, 120 patients were selected, and 50 patients were confirmed as FH and 70 subjects were confirmed as healthy controls. Genotyping was performed with polymerase chain reaction followed by restriction fragment length polymorphism analysis using ApaI, BsmI, TaqI and FokI polymorphisms in the VDR gene. The current study results confirmed no association between clinical characteristics studied between FH cases and controls (p>0.05). Hardy Weinberg Equilibrium analysis was present in ApaI and FokI polymorphisms (p<0.05). Only ApaI (C vs A: OR-15.1 (95% CI:5.78-39.41); p<0.001; AC+CC vs AA: OR-6.59 (95% CI:2.42-17.95); p=0.0006) and BsmI (G vs A: OR-2.88 (95% CI:1.54-5.38); p=0.0006 and AG+GG vs AA: OR-3.79 (95% CI:1.72-8.35); p=0.0007) polymorphisms showed both allele and genotype association between FH patients and controls. ANOVA analysis confirmed that TG levels were associated (p=0.02) with combination of heterozygous and homozygous genotypes present in all four polymorphisms studied in this population. ApaI and BsmI polymorphisms in the VDR gene showed association with FH patients in the Saudi Population.

Biochemical markers and FokI and TaqI vitamin D receptor genes polymorphism in rheumatoid arthritis

BackgroundPrevious studies have reported the role of genes in different metabolic processes in the human body, and any variation in gene polymorphisms could lead to disturbances in these processes and different diseases.ObjectiveThis study aimed to compare vitamin D receptor (VDR) FokI and TaqI genotypes in terms of parathyroid hormone (PTH) and some biomarkers of inflammation and susceptibility to rheumatoid arthritis (RA) disease.MethodsThis study included 100 patients with rheumatoid arthritis (RA). Genotyping was performed by polymerase chain reaction (PCR) and examined by specific restriction enzymes using restriction fragment length polymorphism (RFLP). Serum intact PTH, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), and anti-cyclic citrullinated peptide antibodies (ACCPs) levels were measured.ResultsAn increased PTH level (> 65 pg/ml) was found in 8% of patients. No significant differences among FokI and TaqI vitamin D receptor genes polymorphism regarding positive and negative RF or ACCPs were found. A significant difference was found among FokI (p = 0.009) and none in TaqI genotypes regarding intact parathyroid hormone level categories. No significant correlation was found between the serum intact PTH level and ESR or CRP levels (P = 0.13 and 0.28, respectively). The parathyroid hormone level was not a good predictor for RF or ACCPs (P = 0.5 and 0.06, respectively).ConclusionThe FokI gene may play a role in controlling PTH levels in patients with RA. There was no significant correlation found between the serum intact PTH level and RA severity according to ESR and CRP inflammatory biomarkers. There are no differences between VDR genes FokI and TaqI polymorphism in terms of RA susceptibility (for RF and ACCPs).

Association between course of multiple sclerosis and polymorphisms of calcitriol receptor gene VDR FokI (rs2228570), BSMI (rs1544410), TaqI (rs731236), ApaI (rs7975232)

Objective. To evaluate the relationship between the frequency of exacerbations and the rate of progression of multiple sclerosis (MS) and polymorphisms of the calcitriol receptor gene VDR FokI (rs2228570), BSMI (rs1544410), TaqI (rs731236), ApaI (rs7975232).Material and methods. Ninety patients with relapsing-remitting MS took part in the study. All patients are Caucasians, were born and lived in the Altai region of the Russian Federation. Genotyping was performed by TaqMan probes.Results. A protective effect of the TT genotype VDR FokI (rs2228570) on the risk of increasing disability of more than 0.75 points per year according to the expanded disability scale was found (p = 0.034). The protective effect of the TT genotype of the TaqI polymorphism (rs731236) on exacerbations of MS more than once a year (p = 0.041) was also revealed. Associations of the MS course with other studied polymorphisms were not found.Conclusions. It can be assumed that the VDR FokI (rs2228570) and TaqI (rs731236) polymorphisms may influence the course of relapsing-remitting MS. The mechanisms of these influences may include the modulation of immune-inflammatory responses in the central nervous system, which are a key link in the MS pathogenesis.