Vitamin D Receptor Polymorphisms Research Articles

Serum 25-hydroxyvitamin D, genetic susceptibility and abdominal aortic aneurysm risk.

The association of serum 25-hydroxyvitamin D [25(OH)D] and genetic polymorphisms of the vitamin D receptor (VDR), and the vitamin D binding protein (VDBP) with incident abdominal aortic aneurysm (AAA) remains uncertain. To investigate whether serum 25(OH)D, genetic polymorphisms of VDR and VDBP, genetic susceptibility to AAA, and the interactions among these factors influence the risk of incident AAA. Retrospective cohort study. UK Biobank. 447,529 participants without a diagnosis of prevalent aortic aneurysm or aortic dissection at baseline. Serum 25(OH)D concentration. Incident AAA. During a median follow-up of 12.5 years, 2,042 participants developed incident AAA. A significant inverse association between serum 25(OH)D and incident AAA was observed (per SD increment, HR, 0.92; 95%CI, 0.88-0.96), which was particularly pronounced in older individuals and those without diabetes (both P for interaction <0.05). Compared to participants with serum 25(OH)D ≥ 50 nmol/L, those with serum 25(OH)D between 25 and <50 nmol/L and <25 nmol/L exhibited a significant higher risk of incident AAA. In the 371,621 participants with genetics assessment, individuals carrying AA alleles of ApaI SNP had a significant increased risk of incident AAA compared to those carrying CC alleles (HR, 1.16; 95%CI, 1.02-1.32). The inverse association between serum 25(OH)D and incident AAA was stronger in individuals with intermediate or high genetic risk for AAA (P for interaction = 0.048). There was a significant inverse association between serum 25(OH)D and AAA incidence, particularly among individuals with higher genetic risk for AAA, older age, and without diabetics.

Vitamin D Receptor Gene Polymorphisms Differentiated Between Tuberculosis Disease and Infection: Causal Association Study.

Latent tuberculosis infection (LTBI) is a critical stage in tuberculosis (TB)control, and few studies have addressed the role of vitamin D receptor(VDR) gene polymorphisms in differentiating between TB and late-onset TB from an immunogenetic perspective. Recruitment of tuberculosis patients and latently infected population in Urumqi, Xinjiang, and use of propensity score matching(PSM) to match the two groups and control confounding to further construct a Bayesian network to analyze causal associations between VDR polymorphisms and tuberculosis disease status. 137 LTBI and 237 TB were obtained through PSM. Logistic regression showed that the VDR gene BsmI locus, TaqI locus, and ApaI locus were associated with a higher risk of TB in a codominant model (P<0.05). Further Bayesian network construction showed that occupation and being a VDR gene BsmI locus were direct influences on TB disease status, and the VDR gene TaqI locus played an indirect role through the BsmI locus, and the probability of TB risk was highest in individuals with manual labour and BsmI locus of the C/T type, which was 84.15%. Bayesian network modelling intuitively revealed that individuals with a C/T type of BsmI locus and physical labour are at high risk of TB compared with TB infection, and they are key factors between with TB disease, providing reference evidence for controlling TB progression.

Vitamin D in Cancer Prevention and Treatment: A Review of Epidemiological, Preclinical, and Cellular Studies.

Inhibition of human carcinomas has previously been linked to vitamin D due to its effects on cancer cell proliferation, migration, angiogenesis, and apoptosis induction. The anticancer activity of vitamin D has been confirmed by several studies, which have shown that increased cancer incidence is associated with decreased vitamin D and that dietary supplementation of vitamin D slows down the growth of xenografted tumors in mice. Vitamin D inhibits the growth of cancer cells by the induction of apoptosis as well as by arresting the cells at the G0/G1 (or) G2/M phase of the cell cycle. Aim and Key Scientific Concepts of the Review: The purpose of this article is to thoroughly review the existing information and discuss and debate to conclude whether vitamin D could be used as an agent to prevent/treat cancers. The existing empirical data have demonstrated that vitamin D can also work in the absence of vitamin D receptors (VDRs), indicating the presence of multiple mechanisms of action for this sunshine vitamin. Polymorphism in the VDR is known to play a key role in tumor cell metastasis and drug resistance. Although there is evidence that vitamin D has both therapeutic and cancer-preventive properties, numerous uncertainties and concerns regarding its use in cancer treatment still exist. These include (a) increased calcium levels in individuals receiving therapeutic doses of vitamin D to suppress the growth of cancer cells; (b) hyperglycemia induction in certain vitamin D-treated study participants; (c) a dearth of evidence showing preventive or therapeutic benefits of cancer in clinical trials; (d) very weak support from proof-of-principle studies; and (e) the inability of vitamin D alone to treat advanced cancers. Addressing these concerns, more potent and less toxic vitamin D analogs have been created, and these are presently undergoing clinical trial evaluation. To provide key information regarding the functions of vitamin D and VDRs, this review provided details of significant advancements in the functional analysis of vitamin D and its analogs and VDR polymorphisms associated with cancers.

Association of VDR Polymorphisms with Muscle Mass Development in Elite Young Soccer Players: A Pilot Study.

The vitamin D receptor (VDR) is an important candidate gene in musculoskeletal phenotypes. Polymorphisms in the VDR have been previously associated with several pathologies and muscular strength in athletes and elderly people; however, the literature reported contradictory results. The object of this research was to verify the association between the most studied VDR variants (rs2228570, rs7975232, and rs1544410) and the increase in muscle mass in elite young soccer players. A sample of 55 soccer players (15-18 years old) from a professional team were selected for this study. DNA was extracted by the salting-out method, and polymorphisms were genotyped by PCR-RFLP, followed by 2% agarose gel electrophoresis. To test the effect of the three SNPs (single nucleotide polymorphisms), a logistic regression analysis was applied. The body composition determination was carried out through the skinfold thickness method, and the muscular area of the arm and lower limb were calculated using the Frisancho formula. All three polymorphisms met the Hardy-Weinberg equilibrium (p > 0.05) and their frequencies fell within the worldwide variability. A significant correlation between rs1544410 and the increase in calf muscle mass was observed. Individuals carrying the A allele showed higher calf muscular mass than those carrying the G allele (p = 0.034). Moreover, a haplotype analysis applied to the two SNPs in linkage disequilibrium (rs7975232 and rs1544410) showed that the AG haplotype appeared negatively correlated to the calf muscle area. In conclusion, we confirm an association between VDR polymorphisms and muscular mass that could encourage the genetic screening of the VDR gene to identify a potential risk of injury and for individual nutritional interventions.

Inflammation and Vitamin D Receptor Polymorphism: Impact on All-Cause and Cardiovascular Mortality in Mexican Women on Dialysis.

Mineral bone disease (MBD) is common in dialysis patients. Genetics and the hormonal environment influence the clinical picture and outcomes of women. This study aimed to determine how these factors affect mortality. In 234 female dialysis patients on Continuous Ambulatory (48%) or Automated (29%) Peritoneal Dialysis or Hemodialysis (23%), MBD biochemical variables, as well as bone density and genetic Bsm1 polymorphism of vitamin D receptor (VDR) were performed at baseline. The cohort was followed-up by 17 (IQ range 15-31) months. According to VDR polymorphism, the distribution of patients was bb: 64% and BB+Bb: 36%. Fifty-five patients died from all-cause mortality; the hs-C-reactive protein level was the most significant risk in multivariate Cox analysis. Nineteen died from cardiovascular mortality. None of the variables were significant for cardiovascular mortality. Patients with bb plus inflammation had the highest risk in the analysis; the significance persisted after adjustment for age, diabetes, and parathyroid hormone levels HR 2.33 (95% CI, 1.01-8.33) and after further adjustment for time on dialysis, albumin, and Osteoprotegerin levels HR 3.49 (95% CI, 1.20-10.9). The presence of the bb genotype from VDR and inflammation had the highest risk of death from all-cause mortality in females on CAPD, APD, and HD patient.

Common variants of vitamin D receptor gene polymorphisms and risk of gastric cancer: A meta-analysis.

While earlier studies have suggested that variations in the vitamin D receptor (VDR) gene could influence the susceptibility to gastric cancer (GC), the results have shown inconsistency. This meta-analysis aimed to examine the association of 5 common polymorphisms in VDR, including Taq1 rs731236 (T > C), FokI rs2228570 (C > T), Cdx2 rs11568820 (G > A), BsmI rs1544410 (G > A), and ApaI rs7975232 (G > T) with the risk of GC. A comprehensive search was carried out in PubMed, Web of Science, and Scopus to identify relevant studies published until January 2024. Odds ratios (ORs) with 95% confidence intervals (CIs) were utilized to assess the magnitude of associations. Nine studies, with 2837 participants (1215 GC cases and 1622 healthy controls), were eligible. The FokI rs2228570 polymorphism showed a significant correlation with heightened susceptibility to GC under the recessive model (OR = 1.52; 95% CI: 1.06-2.19) and homozygote comparison (TT vs CC; OR = 1.59; 95% CI: 1.09-2.31). Taq1 rs731236 was also linked to an elevated risk of GC under the same models (recessive OR = 1.65; 95% CI: 1.14-2.39; homozygote OR = 1.68; 95% CI: 1.11-2.54). In the sensitivity analysis, when studies not adhering to Hardy-Weinberg equilibrium were excluded, the relationship between FokI rs2228570 polymorphism and GC disappeared, while the association for Taq1 rs731236 remained consistent. No significant association was identified for BsmI rs1544410, ApaI rs7975232, and Cdx2 rs11568820. This study revealed that FokI rs2228570 and Taq1 rs731236 polymorphisms of VDR might be linked to the odds of GC.

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.

Association of vitamin D status and vitamin D receptor polymorphism in diabetic foot ulcer patients: A prospective observational study in a South-Indian tertiary healthcare facility.

Objective of the study was to find the association of vitamin D receptor (VDR) polymorphisms (Fokl, Taql and Apal) with vitamin D levels in diabetic foot ulcer (DFU) patients in South India. In this case-control study, plasma vitamin D levels and VDR genotype frequencies of 70 cases (DFU patients) were compared with 70 diabetic (diabetes mellitus [DM] [non-DFU]) patients and 70 apparently healthy controls (HC) from South India. Plasma vitamin D levels were measured using the ELISA technique, and genotyping of VDR polymorphisms was carried out using real-time polymerase chain reaction. Logistic regression was used to find the association between DFU versus HC and DFU versus DM traits. Association analysis was performed based on additive, dominant and recessive models with age and gender as covariates. A 45.7% of DFU patients have sufficient vitamin D levels than 48.6% and 40% of DM patients and HC, respectively. Linkage disequilibrium analysis for DFU versus HC and DFU versus DM traits shows that single nucleotide polymorphisms (SNPs) Taq1 (rs731236) and Apal (rs7975232) are in strong linkage disequilibrium in DFU patients. The alleles and genotype frequencies were similar in all three groups. Although the additive model does not show statistical significance, age and sex correlate with the three SNPs (Fokl, Taql and Apal). No association was found between VDR gene polymorphisms and vitamin D levels in DFU patients in Southern India. On the other hand, age and sex correlate with the three SNPs.

Association between Vitamin D Receptor Polymorphisms, Tight Junction Proteins and Clinical Features of Adult Patients with Atopic Dermatitis.

Few studies have explored the intricate connections between vitamin D receptor (VDR) gene polymorphisms, VDR, tight junction (TJ) protein expression and clinical features of atopic dermatitis (AD). From 43 adult AD patients, VDR polymorphisms were genotyped from peripheral blood samples using polymerase chain reaction-restriction fragment length polymorphism. VDR, occludin, claudin-1 and ZO-1 protein expression from skin lesion biopsies were assessed by immunohistochemistry. The A1012G heterozygous VDR polymorphism exhibited a lower odds ratio (OR) for juvenile AD onset (OR: 0.046, 95% CI 0.004-0.51, p=0.012). In contrast, the presence of ≥2 homozygous VDR polymorphisms were significantly associated with positive skin prick test (SPT) (10/20, 50%) vs. negative SPT (1/23, 4.3%; p=0.0003). The most highly expressed TJ proteins in lesions of AD patients were claudin-1 and zonulin-1 (ZO-1), while VDR and occludin were less prevalent. A significant correlation was observed between ZO-1 expression and a body mass index ≥30 kg/m2 (OR: 12.1, 95% CI 1.06-137.9, p=0.045). Claudin-1 expression was associated with a positive SPT (OR: 8.23, 95% CI 1.04-65.5, p=0.046) and serum 25(OH)D levels were negatively correlated with ZO-1 expression (rho= -0.43, p=0.0058). This study provides novel insights into the relationship between VDR gene polymorphisms, VDR, TJ protein expression, and clinical features in adult AD patients, highlighting a significant role of vitamin D in the pathophysiology of this disease.

Frequency of rs731236, rs7975232 and rs1544410 single nucleotide polymorphisms of Vitamin-D Receptor (VDR) gene among the Kazakh ethnic group

In the article the pilot study results of the genotypes and individual allele’s frequency of single nucleotide polymorphisms (SNPs) rs731236, rs7975232 and rs1544410 in vitamin D receptor (VDR) gene were presented. The participants were representatives of the Kazakh ethnic group. The SNPs were determined by real-time polymerase chain reaction using the amplification-refractory mutation system (ARMS) technology. The relevance of the study is that rs731236, rs7975232 and rs1544410 contribute to the regulation of VDR gene expression. This affects the synthesis of the VDR protein and its activity as a transcription factor. VDR regulates various metabolic pathways, including the immune response to infectious diseases. In rs731236, the A allele (68.9 %) prevailed over the G (31.1 %). The AA, AG and GG genotypes were 52.1 %, 33.6 % and 14.3 %, respectively. For rs7975232, there were no significant differences in the alleles A and C (42.4 % vs. 57.6 %). There was a predominance of AC and CC genotypes (39.5 % and 37.8 %, respectively), over AA (22.7 %). Allele A of rs1544410 was not found in the Kazakh population. The allele C was 65.6 %, T — 25.6 %, and G — 8.8 %. The frequencies of the CC and CT genotypes were similar (40.3 % vs. 39.5 %). It is possible to study the influence of these SNPs on COVID-19 susceptibility among Kazakhs.

Exploring the Role of Vitamin D, Vitamin D-Dependent Proteins, and Vitamin D Receptor Gene Variation in Lung Cancer Risk.

Lung cancer has an unfavorable prognosis with a rate of low overall survival, caused by the difficulty of diagnosis in the early stages and resistance to therapy. In recent years, there have been new therapies that use specific molecular targets and are effective in increasing the survival chances of advanced cancer. Therefore, it is necessary to find more specific biomarkers that can identify early changes in carcinogenesis and allow the earliest possible treatment. Vitamin D (VD) plays an important role in immunity and carcinogenesis. Furthermore, the vitamin D receptor (VDR) regulates the expression of various genes involved in the physiological functions of the human organism. The genes encoding the VDR are extremely polymorphic and vary greatly between human populations. To date, there are significant associations between VDR polymorphism and several types of cancer, but the data on the involvement of VDR polymorphism in lung cancer are still conflicting. Therefore, in this review, our aim was to investigate the relationship between VDR single-nucleotide polymorphisms in humans and the degree of risk for developing lung cancer. The studies showcased different gene polymorphisms to be associated with an increased risk of lung cancer: TaqI, ApaI, BsmI, FokI, and Cdx2. In addition, there is a strong positive correlation between VD deficiency and lung cancer development. Still, due to a lack of awareness, the assessment of VD status and VDR polymorphism is rarely considered for the prediction of lung cancer evolution and their clinical applicability, despite the fact that studies have shown the highest risk for lung cancer given by TaqI gene polymorphisms and that VDR polymorphisms are associated with more aggressive cancer evolution.

Prevalence and effects of Vitamin D receptor polymorphism on bone mineral density and metabolism in patients with systemic sclerosis: a preliminary study

Patients with systemic sclerosis (SSc) have a disproportionately high prevalence of reduced bone mineral density (BMD). Polymorphisms of the vitamin D receptor (VDR) gene have been associated with osteoporosis in patients with autoimmune diseases. The aim of this study was to investigate the prevalence and possible effects of VDR polymorphism on BMD and bone metabolism in patients with SSc. In patients with SSc measurement of BMD was performed using dual-energy X-ray absorptiometry. VDR polymorphisms (FokI, BsmI) were genotyped using restriction fragment length polymorphism analysis. Markers of bone metabolism (calcium, osteocalcin, β-crosslaps) were determined. Primary endpoint was the prevalence of VDR gene polymorphisms and the association with reduced BMD. Secondary endpoints included associations between bone metabolism and VDR gene polymorphism. 79 Caucasian patients with SSc were included. Overall, 83.5% had reduced BMD (51.9% osteopenia, 31.6% osteoporosis). The prevalence of VDR gene polymorphism (73% BsmI, 77% FokI) was comparable to studies in healthy and rheumatic populations. The homozygous presence of FokI polymorphism, but not BsmI, was significantly associated with reduced axial BMD. Fokl polymorphism was significantly associated with reduced CTX levels, although changes remained within the reference limits. VDR polymorphisms can frequently be found in patients with SSc in comparable prevalence to healthy and rheumatic populations. The homozygous presence of FokI polymorphism, but not BsmI, was significantly associated with reduced axial BMD. This could be a possible contributor for the high prevalence of reduced BMD in 83.5% of patients with SSc in this study.Trial registration. DRKS00032768, date: 05.10.2023, retrospectively registered.

Vitamin D and it’s Association with FokI VDR Polymorphism in Patients with Asthma-COPD Overlap

Background: Asthma-COPD overlap is a new phenotype in respiratory ailments. It has been shown that this group of patients might possess vitamin D3 deficiency. The association of vitamin D receptor (VDR) gene polymorphism with serum vitamin D status in ACO patients has not been investigated yet. Objective: To assess the association of VDR gene polymorphism (FokI) with serum vitamin D status in patients with Asthma-COPD overlap. Methods: This cross-sectional study was carried out in the Department of Physiology of Bangabandhu Sheikh Mujib Medical University, Dhaka, from January 2018 to July 2018 on 23 (twenty-three) patients (aged ≥40 years) with ACO. For comparison, 24 (twenty-four) apparently healthy age, smoking duration and BMI matched subjects were selected. For all participants single nucleotide polymorphism of VDR gene FokI (rs10735810) was done by DNA extraction, polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Vitamin D3 was measured by using automated analyzer: ARCHITECT Plus ci4100. The results were expressed as mean with standard error (mean±SEM) and frequency distribution. The data were statistically analyzed by Graphpad prism (Version 7) using independent sample ‘t’ test, two sample proportion test, Fisher exact test and ANOVA test. In the interpretation of results, ≤0.05 level of probability (p) was accepted as significant. Results: The mean±SEM of serum 25(OH)D were 16.37±0.78 and 18.46±1.01 ng/ml in control and study groups, respectively. The frequency distribution of FokI genotype was 86.95% (FF), 8.69% (Ff), 4.35% (ff) and 91.66% (FF), 4.17% (Ff), 4.17% (ff) in ACO patients and healthy subjects, respectively. When FoKI VDR SNP was analyzed with serum vitamin D status in patients with ACO, statistically no association was seen. Conclusions: FokI VDR SNP is not associated with serum vitamin D status in patients with ACO. J Rang Med Col. March 2024; Vol. 9, No. 1: 22-27

Comparing vitamin D receptor gene polymorphisms in rs11568820, rs7970314, rs4334089 between COVID-19 patients with mild and severe symptoms: a case control study

The associations of vitamin D receptor (VDR)- single nucleotide polymorphisms (SNPs) with the symptoms of COVID-19 may vary between patients with different severities of COVID-19. Therefore, in the present study, we aim to compare VDR polymorphisms in severe and mild COVID-19 patients. In this study, a total number of 85 hospitalized patients and 91 mild/moderate patients with COVID-19 were recruited. SNPs in VDR genes were determined using ARMS and then confirmed by sanger sequencing. The mean (SD) age of participants in hospitalized and non-hospitalized group was 59.0 (12.4) and 47.8 (14.8) years, respectively. Almost 46% of participants in hospitalized and 48% of participant in non-hospitalized group were male. The frequency of TT genotype of SNP rs11568820 was significantly lower in hospitalized than non-hospitalized group (3.5% vs. 17.6%; P = 0.018). However, there was no significant differences between genotypes of SNPs rs7970314 and rs4334089 and also alleles frequencies in all SNPs of two groups. The genotype of rs11568820 SNP had an inverse association with hospitalization of patients with COVID-19 after adjustment for comorbidities [OR 0.18, 95% CI 0.04, 0.88; P = 0.034]. While, there was no relationship between genotypes of SNPs rs7970314 and rs4334089 and hospitalization. The TT genotype of rs11568820 plays protective role in sever COVID-19 and hospitalization. Further studies with a large sample size which consider various confounding factors are warranted to confirm our results.

Vitamin D receptor gene polymorphisms role in COVID-19 severity: Results of a Mexican patients' cohort.

Vitamin D status has been involved with coronavirus disease 19 (COVID-19) severity. This may be mediated by vitamin D metabolism regulatory genes. Of interest is the vitamin D receptor (VDR) gene, which has been previously associated with other inflammatory and respiratory diseases. In order to investigate the role of VDR gene polymorphisms in COVID-19 severity and outcome, a total of 292 COVID-19 patients were classified according to severity in moderate (n=56), severe (n=89) and critical (n=147) and, according to outcome in survivor (n=163) and deceased (n=129), and analysed for FokI and TaqI VDR gene polymorphisms by polymerase chain reaction-based restriction enzyme digestion. The FokI and TaqI single nucleotide polymorphisms (SNPs) were not associated with COVID-19 severity or mortality individually but when analysed by haplotype, TC was associated with an increased risk of presenting critical COVID-19. Additionally, FokI CT genotype was more frequent in COVID-19 patients with hypertension, and T allele carriers presented higher aspartate aminotransferase levels. Our results suggest a relationship between VDR FokI and TaqI SNPs and COVID-19 severity in Mexican population. Although there are some previous reports of VDR polymorphisms in COVID-19, this represents the first report in Latin American population. Further studies on other populations are encouraged.

Delving the vitamin D receptor variation and expression profiles in the context of type 2 diabetes among families.

Vitamin D is essential for insulin secretion and sensitivity. Consequently, its inadequacy is linked to higher insulin resistance and Type 2 Diabetes (T2D). The Vitamin D receptor (VDR) gene is one potential candidate for T2D, and multiple polymorphisms in VDR have been examined in various populations, but no conclusive answers have been provided. This study was designed to evaluate the susceptibility of VDR gene polymorphism and its expression in diabetic families in Pakistan. In this family-based study, twenty diabetic families with a positive family history of T2D and at least three T2D patients were recruited from outpatient clinics and public hospitals. The current study comprised 143 individuals with 55 affected and 88 unaffected individuals.Blood samples of the selected families were collected. DNA was extracted from the collected samples and the PCR-RFLP method was followed to identify the genotyping and RT-qPCR for expression. Phenotypic and genotypic pedigrees of the families were developed by the progeny online tool. The association values of SNPs were determined by TDT and DFAM analysis implemented on Plink software. The results explained a significant familial aggregation among phenotypic characters including Age, Gender, BMI (body mass index), age of disease diagnosis, disease duration, and blood pressure in the probands, affected FDRs (First Degree Relatives) and affected SDRs (Second Degree Relatives). A significant association of rs731236 C/T (OR = 1.522), rs2228570 C/T (OR = 1.327) with p < 0.05. Whereas, for rs1544410 G/A (OR = 0.9706) and rs7975232 T/G (OR = 0.7368) no considerable association evidence was seen (p > 0.05) in families. The mRNA expression of VDR increased threefold (p = 0.0204) in patients compared to controls. Variation-based expression analysis exhibited that the rs2228570 genotype influences the expression. A linkage was found among the FDRs with probands. Variation in the gene VDR at loci rs731236 and rs2228570 was associated with familial T2D. However further research is required to explore more genetic factors that could influence T2D risks in families.

Relationship between vitamin D receptor genotypes (FOK1rs2228570) and IL18 gene expression in sample of multiple sclerosis Iraqi patients

BACKGROUND: Multiple Sclerosis known as MS, this chronic inflammatory demyelinating condition affects the nervous system. It is a heterogenic and multifactorial disease. The goal of the current study was to investigate the relationship between MS patients’ IL18 gene expression and the vitamin D receptor gene polymorphism (FOK1rs2228570). OBJECTIVE: The aim of the study to investigate the association of vitamin D receptor (FOK1rs2228570) gene polymorphism and pro inflammatory cytokine (IL18) gene expression among multiple sclerosis Iraqi patients. Detection VDR polymorphism and determine whether this SNP is involved in susceptibility to multiple sclerosis and estimation IL18 gene expression and explore its relation with multiple sclerosis susceptibility. METHODS: Blood samples were taken from 75 MS patients in Iraq (30 men and 45 women), as well as from 75 volunteers who seemed to be in a favorable state of health and fell within the age range of 20 to 50 years. Tetra-ARMS Polymerase Chain Reaction (Tetra-ARMS PCR) was used to find polymorphisms in the vitamin D receptor (VDR) gene, and Real-time Polymerase Chain Reaction (RT-PCR) was used to measure IL18 gene expression. RESULTS: The findings from the analysis of VDR gene polymorphism in patients with MS indicated that the wild-type genotype T/T was present in 8 individuals, accounting for 10.6%, the heterogeneous genotype TC was 36 (48%), and the homogeneous genotype CC was 31 (41.3%), whilst T allele frequency was 52(34.6%) and C allele was 98(65.3%) with (P⩽ 0.01) significant difference and even as in control T/T genotype was 49(65.3%), TC genotype was 21(28%), CC genotype was 5(6.66%), T allele frequency was 119(79.3%) and C allele was 31(20.6%) with significant difference (P⩽ 0.001). While estimation of IL18 expression showed high elevation in patients’ group (2.59 ± 0.51 fold) by significance difference (P⩽ 0.5) when compared to control group (1.35 ± 0.14 fold). The relationship between IL18 gene expression with VDR variant in MS patients demonstrated a significant rise (2.9 ± 0.51 fold) at CC genotype patients in IL18 folding gene expression, followed by (4.6 ± 0.17 fold) in TC genotype patients and finally (1.4 ± 0.08 fold) in TT genotype patients with highly significant (P⩽ 0.01). CONCLUSION: The VDR(FOK1rs2228570) genotype was significantly correlated with IL18 expression in MS patients from Iraq.

Vitamin D Status, Vitamin D Receptor Polymorphisms, and Risk of Type 2 Diabetes: A Prospective Cohort Study.

Vitamin D status has been associated with risk of type 2 diabetes (T2D), but evidence is scarce regarding whether such relation differs by glycemic status. To prospectively investigate the association between serum 25-hydroxyvitamin D (25(OH)D) and risk of incident T2D across the glycemic spectrum and the modification effect of genetic variants in the vitamin D receptor (VDR). This prospective study included 379 699 participants without T2D at baseline from the UK Biobank. Analyses were performed according to glycemic status and HbA1c levels. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% CIs. During a median of 14.1 years of follow-up, 6315 participants with normoglycemia and 9085 patients with prediabetes developed T2D. Compared with individuals with 25(OH)D < 25 nmol/L, the multivariable-adjusted HRs (95% CIs) of incident T2D for those with 25(OH)D ≥ 75 nmol/L was 0.62 (0.56, 0.70) among the normoglycemia group and 0.64 (0.58, 0.70) among the prediabetes group. A significant interaction was observed between 25(OH)D and VDR polymorphisms among participants with prediabetes (P interaction = .017), whereby the reduced HR of T2D associated with higher 25(OH)D was more prominent in those carrying the T allele of rs1544410. Triglyceride levels mediated 26% and 34% of the association between serum 25(OH)D and incident T2D among participants with normoglycemia and prediabetes, respectively. Higher serum 25(OH)D concentrations were associated with lower T2D risk across the glycemic spectrum below the threshold for diabetes, and the relations in prediabetes were modified by VDR polymorphisms. Improving the lipid profile, mainly triglycerides, accounted for part of the favorable associations.

Association between Vitamin D Receptor Fokl and Bsml Gene Polymorphism and Diabetes Mellitus in Nepalese Population

Vitamin D being involved in the secretion of insulin is a known fact. Moreover, studies have shown that steroids might be a factor in influencing insulin sensitivity. Vitamin D receptor (VDR), a factor required for genetic regulation involving vitamin D, thus can be regarded as a good candidate for Diabetes Mellitus (DM). Several studies have been conducted on the association between VDR polymorphism and the risk of DM but did not provide clear-cut answers. This study was conducted to search for the involvement of FokI and BsmI polymorphisms of the VDR gene with DM in a Nepalese population. A total of 200 blood samples were collected; 100 from clinically diagnosed DM patients and 100 from healthy controls. DNA was extracted from blood by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis, where FokI and BsmI primers as well as restriction enzymes were used. After restriction digestion, SNPs of FokI (T/C) [rs2228570] and BsmI (A/G) [rs1544410] were assayed using agarose gel electrophoresis. As patients and controls were likened for genotype distribution and allelic frequencies, it was found that the frequency of VDR gene BsmI rs1544410 differed significantly (p &lt; 0.05, each) between cases and control whereas A allele was dominant (91%) in healthy controls with Odd ratio (OR) of 0.55, unlike VDR Fokl were not significantly associated between subjects and control. The data obtained from this research suggests that the VDR gene (especially BsmI) is associated with the risk of DM.

Association of Vitamin D Deficiency and Vitamin D Receptor Gene Polymorphisms with Type 1 Diabetes Risk: A South Indian Familial Study

Vitamin D is a potent immune modulator and is associated with autoimmune diseases, including type 1 diabetes (T1D). The vitamin D levels and its receptor gene polymorphisms together in T1D are not yet investigated in the South Indian population. The present study focused on exploring the significance of vitamin D levels and vitamin D receptor (VDR) gene polymorphisms with the risk of developing T1D in the South Indian population. Patients with T1D and unaffected first-degree relatives (FDRs) were included in this study. Genotyping of VDR polymorphisms at four different loci (FokI- F/f, BsmI- B/b, TaqI- T/t, and ApaI- A/a) was assessed through the amplification refractive mutation system-polymerase chain reaction method. Serum vitamin D levels were measured in 98 T1D patients and 75 age- and sex-matched siblings. A total of 120 patients with T1D and 214 FDRs were included. Vitamin D deficiency (VDD) was observed in a higher proportion of T1D patients than in controls (52% vs. 32%; p<0.03). The frequency of the FokI-FF genotype was significantly higher [odds ratio (OR)=1.66; p<0.03] in T1D patients conferring a susceptible association with the disease. Nevertheless, the increased frequency of heterozygous Ff genotype (OR=0.57; p<0.02) among controls may confer a protective association with T1D. Furthermore, the transmission disequilibrium test revealed over-transmission of ApaI-A (T: U=15/5; p<0.006) and BsmI-B alleles (T: U=17/5; p<0.01) and under-transmission of BsmI-b/ApaI-a/TaqI-T haplotype (T: U=5.4/14.4; p=0.04) from parents to T1D patients. The present study concludes that VDD is the major contributing risk factor to T1D development in the South Indian population. Furthermore, the FokI-FF genotype, BsmI-B, and ApaI-A alleles were positively associated with T1D. In contrast, the FokI-Ff genotype and BsmI-b/ApaI-a/TaqI-T haplotype were negatively associated with T1D.