TaqI Polymorphisms Research Articles

Associations among two vitamin D receptor (VDR) gene polymorphisms (ApaI and TaqI) in acne vulgaris: A pilot susceptibility study.

Acne vulgaris (AV) pathogenesis is multifactorial. Vitamin D (VitD) plays an important role in sebocytes' differentiation and function. Most VitD functions are mediated by the nuclear VitD receptor (VDR) following binding of its biologically active form (1,25 dihydroxyvitamin D3). Genetic variations in VDR gene may cause significant receptor dysfunction and have been found to be associated with many inflammatory skin diseases. Two adjacent single nucleotide polymorphisms of VDR, ApaI (rs7975232) and TaqI (rs731236), were commonly studied. To evaluate the association between VDR ApaI and TaqI gene polymorphism and AV. This case control study included 30 Egyptian acne patients who attended Dermatology Outpatient Clinic of Al-Zahraa University and Misr University for Science and Technology Hospitals. Thirty age- and sex-matched healthy individuals participated as controls. VDR gene ApaI and TaqI polymorphisms were examined by polymerase chain reaction restriction fragment length polymorphism. Serum 25(OH)D was measured in all participants. Patients had significant decrease in ApaI A allele and AATT combined genotype (60%, 3.3%) than controls (78.3%, 20%), respectively, and significant increase in TaqI tt genotype and t allele (46.7%, 63.3%) than controls (13.3%, 41.7%), respectively. Patients showed significantly lower serum 25(OH)D3 concentration than controls. Polymorphisms of ApaI and TaqI may have a role in the pathogenesis of AV as A allele and AATT combined genotype could be considered protective against acne development and tt genotype and t allele may increase the risk of AV development. VitD deficiency can be considered as a risk factor for AV development.

Prognostic significance of vitamin D receptor (VDR) gene polymorphisms in liver cirrhosis

Several polymorphisms in the vitamin D receptor (VDR) are associated with the occurrence of chronic liver disease. Here, we investigated the association between BsmI, ApaI, TaqI and FokI VDR polymorphisms and the severity of liver cirrhosis in relation to serum cytokine and lipopolysaccharide binding protein (LBP) levels and their role on survival in cirrhotic patients. We found that patients harboring the BB genotype had higher MELD score, and they were mainly at CP stage C; patients harboring the AA genotype had increased LBP, IL-1β and IL-8 levels, and they were mostly at CP stage C; TT genotype carriers had higher MELD score and they were mainly at CP stage C and FF genotype carriers had lower IL-1β levels when compared to Bb/bb, Aa/aa, Tt/tt and Ff/ff genotypes respectively. In the multivariate analysis ApaI, BsmI and TaqI polymorphisms were independently associated with liver cirrhosis severity. In the survival analysis, the independent prognostic factors were CP score, MELD and the FF genotype. Our results indicate that the ApaI, TaqI and BsmI polymorphisms are associated with the severity of liver cirrhosis, through the immunoregulatory process. Survival is related to the FF genotype of FokI polymorphism, imparting a possible protective role in liver cirrhosis.

Polymorphisms in vitamin D receptor gene, but not vitamin D levels, are associated with polycystic ovary syndrome in Brazilian women

This study aimed to investigate the association between vitamin D (VitD) levels, polymorphisms in VDR gene (ApaI, BsmI, FokI, and TaqI) and the polycystic ovary syndrome (PCOS) in a group of Brazilian women. A total of 100 patients with PCOS and 100 control women were included. The quantification of 25-hydroxyvitamin D (25(OH)D) was performed in high-performance liquid chromatography (HPLC). Polymorphisms on VDR gene were performed by PCR-RFLP. The BsmI AG genotype was more frequent in PCOS group, while the GG genotype was more frequent in the control group (p = .007). The frequency of the Taql CC genotype was higher in PCOS group, while the CT genotype was the most frequent in the control group (p = .021). Mean serum VitD levels were similar between the groups. However, there was a negative correlation between VitD levels and Ferriman-Gallwey score (p = .031, r = −.260) in the PCOS group. The TaqI and BsmI polymorphisms were associated with PCOS. Moreover, VitD levels are associated with the clinical hyperandrogenism. The data suggest the role of VitD in PCOS development and its complications.

Fok-I, Bsm-I, and Taq-I Variants of Vitamin D Receptor Polymorphism in the Development of Autism Spectrum Disorder: A Literature Review.

The role of vitamin D in the development of autism spectrum disorder (ASD) is of intensified interest in medical science in recent years. Vitamin D has a significant role in neurogenesis, neuroprotection, and neurodevelopment. Due to the close association of vitamin D with the brain, it has been found that in the pathophysiology of several neuropsychiatric disorders vitamin D receptor (VDR) polymorphism plays a significant role. In this review article, we looked for a relation between VDR polymorphism and ASD. We systemically reviewed all the potential articles on the relation between VDR polymorphism and ASD. We found that several VDR variants FokI, BsmI, and TaqI polymorphisms are related to ASD. Even paternal VDR polymorphism can be a causative factor for ASD in the offspring. The relation between FokI (ff) genotype polymorphism and increased level of serum 1,25(OH)D3 in ASD patients is a very significant finding. Variation of ASD-related genotypes in different ethnic population raises a big question on whether the environmental factors also can do changes in human genotypes leading to ASD.

Vitamin D receptor gene polymorphisms (Apa1 and Taq1) in temporomandibular joint internal derangement/osteoarthritis in a group of Turkish patients.

Genetic variations might play a role in susceptibility to temporomandibular joint internal derangement (TMJ-ID) and osteoarthritis of the joint (TMJOA). Vitamin D receptor (VDR) polymorphisms have been shown to be associated with disc degeneration-linked pathologies, particularly osteoarthritis (OA). The aim of this study was to evaluate whether VDR polymorphisms present susceptibility to TMJ-ID/TMJOA. The study included 49 unrelated TMJ-ID patients with OA (31.7 ± 7.9) that were grouped and evaluated as having anterior disk displacement with reduction (ADDwR, n = 24) (31.58 ± 8.25) and without reduction (ADDwoR, n = 25) (31.8 ± 7.53) and 70 healthy controls (28.22 ± 5.9). DNA was extracted from blood samples using the standard proteinase K/phenol-chloroform method. Apa1 and Taq1 polymorphisms were investigated using a polymerase chain reaction-based restriction fragment length polymorphism assay. When TMJ-ID patients, ADDwR cases and ADDwoR cases versus healthy controls were compared, Apa1 Aa genotype compared to AA genotype had odds ratios of 1.65, 1.79 and 1.64 respectively (p > 0.05). In TMJ-ID women versus healthy women Aa genotype had 2.06 fold (p = 0.15) odds compared to AA genotype. Taq1 results showed that in TMJ-ID patients and ADDwoR cases the Tt genotype had odds ratios of 0.63 and 0.44 fold (p > 0.05) respectively. In TMJ-ID women the Tt and tt genotypes had odds ratios of 0.53 and 0.73 (p > 0.05). Combined VDR genotypes revealed that AATT had a 3.3 fold (p = 1.21) odds ratio while AATt had a 2.0 fold odds ratio (p = 0.29) (OR 0.59, 95% CI 0.23-1.49, p = 0.26) compared to AaTt. Although our results do not confirm susceptibility of VDR polymorphisms to TMJ-ID/TMJOA ,this relation needs to be further evaluated in a large cohort study.

The association between vitamin D receptor gene polymorphisms and hepato-cellular carcinoma in Egyptian patients with chronic liver disease

AimTo evaluate the possible association between vitamin D receptor single nucleotide polymorphisms and hepato cellular carcinoma in Egyptian patients with chronic liver disease. MethodSpecific primer sequences of the vitamin D receptor gene rs1544410, rs7975232, and rs731236 were used to detect vitamin D receptor polymorphisms in blood sample by polymerase chain reaction restriction fragment polymorphism. Allele specific restriction enzymes BsmI, ApaI and TaqI were used to digested PCR amplified products and the bands of specific PCR-RFLP fragments were resolved by 2% Ethidium bromide agrose gel electrophoresis. Genotypes and alleles were identified by their specific banding pattern on the gel electrophoresis via ultraviolet illumination. ResultThe frequencies of the 3 single nucleotide polymorphisms BsmI, ApaI, and TaqI genotype and the haplotype distribution were similar in patients with chronic liver disease either with or without hepato-cellular carcinoma. Neither of vitamin D receptor gene polymorphisms were a risk or protective factor for HCC; nor did these polymorphisms alter the risk for HCC development by coexisting HCC with chronic hepatitis C virus infection. TaqI polymorphism was associated with increased risk of progression of chronic liver disease to liver cell failure and decompensated liver disease. Conclusionvitamin D receptor single nucleotide polymorphisms at BsmI, ApaI, and TaqI did not provide significant association with HCC cancer risk or protection in the overall analysis in Egyptian population with chronic liver disease.

Vitamin D receptor gene (FokI, TaqI, BsmI, and ApaI) polymorphisms in children with urinary tract infection.

Little is known about the genetic background of urinary tract infection (UTI) in children. In this study, vitamin D receptor (VDR) gene polymorphisms were compared between 60 children with UTI (case group) and 60 healthy children (control group). DNA extraction, polymerase chain reaction, and the restriction fragment length polymorphism methods were used to perform the genetic analysis. There was a significant difference between the case and control groups for VDR gene, ApaI and Bsml, polymorphisms (P < 0.05). The frequency of VDR Bb, bb, Aa, and aa genotypes, and the b and a alleles in the case group was significantly higher than that in the control group (P < 0.05). A significant difference was also found between lower UTI and acute pyelonephritis groups for the VDR Apal and Bsml genotypes (P < 0.05). There was no significant difference between children with first UTI and those with more than one UTI for VDR gene polymorphisms (P > 0.05). This study showed that there is a significant relationship between VDR gene, Apal and Bsml, polymorphisms and UTI in children. The results indicate that these polymorphisms may play a role in pathogenesis of UTI.

Single Nucleotide Polymorphisms in the Vitamin D Receptor Gene (VDR) May Have an Impact on Acute Pancreatitis (AP) Development: A Prospective Study in Populations of AP Patients and Alcohol-Abuse Controls.

Vitamin D imbalance is suggested to be associated with the development of pancreatitis. Single nucleotide polymorphisms (SNPs), Apa-1, Bsm-1, Fok-1, and Taq-1, in the vitamin D receptor gene (VDR) are known in various diseases, but not yet in pancreatitis. The aim of this study was to explore possible associations of the four SNPs in the VDR receptor gene in a population of acute pancreatitis patients and alcohol-abuse controls, and to investigate the association with acute pancreatitis (AP) susceptibility. The study population (n = 239) included acute pancreatitis patients (n = 129) and an alcohol-abuse control group (n = 110). All patients met the Diagnostic and Statistical Manual of Mental Disorders (DSM IV) criteria for alcohol dependence. DNA was extracted from peripheral leukocytes and analyzed for VDR polymorphisms using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Odd ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression analysis. To date, we have found allele T in Taq-1 (OR = 2.61; 95% CI: 1.68–4.03; p < 0.0001) to be almost three times more frequent in the AP group compared to the alcohol-abuse control patients. Polymorphism Taq-1 occurring in the vitamin D receptor may have an impact on the development of acute pancreatitis due to the lack of the protective role of vitamin D.

Positive correlation between vitamin D receptor gene FokI polymorphism and colorectal cancer susceptibility in South-Khorasan of Iran.

Colorectal cancer (CRC) is a global public health problem. Despite the major milestone in early diagnosis and treatment of colorectal cancer, the prevalence of CRC rates is still rising. The etiology of CRC is still unknown but we know CRC is influenced by both of environment and genetic factors. In this study, we aimed to elucidate the role of vitamin D receptor gene polymorphic regions; FokI and TaqI single nucleotide polymorphisms, in increasing the risk of colorectal cancer in Birjand population. One hundred patients with CRC and 100 healthy controls recruited to the study. Genotyping was performed by PCR-RFLP (restriction fragment length polymorphism) method technique for all individuals. There were statistically significant differences between ff genotype and f allele of FokI SNP in case and control groups. Our results manifested positive correlation between ff genotype and f allele of FokI SNP with colorectal cancer predisposition (P = 0.035, P = 0.0001 respectively) in South Khorasan population. The present study showed that FokI polymorphism but not TaqI polymorphism may contribute to CRC susceptibility. In addition, ff genotype of FokI polymorphism was associated with CRC risk.

Vitamin D Receptor TaqI Polymorphism Is Associated With Reduced Follicle Number in Women Utilizing Assisted Reproductive Technologies.

Calcitriol, or 1,25-hydroxycholecalciferol, is the active form of vitamin D. It binds and activates vitamin D receptor (VDR). Infertility and defective folliculogenesis have been observed in female vdr-knockout mice; however, whether VDR polymorphisms affect human ovarian responses to controlled ovarian stimulation (COS) remains unclear. We hypothesized that VDR polymorphisms are associated with infertility and COS responses. Thus, we evaluated the association between the TaqI, BsmI, and FokI VDR polymorphisms and ovarian responses in women undergoing COS. In this study, we recruited a control group (n = 121) comprising volunteers with a history of natural conception and a second group of women undergoing COS (n = 70). TaqI, BsmI, and FokI genotyping was performed via restriction fragment length polymorphism analysis or TaqMan qPCR and Sanger sequencing. Intrafollicular 25(OH)D contents were measured in follicular fluid collected from COS patients during oocyte retrieval. Ovarian response parameters were obtained from patient medical records. There were no significant differences in the genotype frequencies of VDR polymorphisms (TaqI, BsmI and FokI) between the control and COS groups. However, the allele frequency of TaqI (C allele) was significantly lower in the COS group than in the control group (p = 0.02). Follicle number but not oocyte number was lower in patients with TaqI polymorphic (TC/CC) genotypes (p = 0.03). Importantly, the ratio between the number of follicles retrieved and intrafollicular estradiol concentrations was higher in patients with the TC/CC TaqI genotypes (p < 0.02). We identified an association between the VDR TaqI polymorphism and reduced follicle number in women undergoing COS, suggesting that VDR signaling affects the ovarian response to stimulation via unknown mechanisms.

BsmI, TaqI, ApaI and FokI VDR polymorphism in women wit and without goiter

BsmI, TaqI, ApaI and FokI VDR polymorphism in women wit and without goiter

Association of VDR gene polymorphisms and 22bp deletions in the promoter region of TLR2Δ22 (-196-174) with increased risk of pulmonary tuberculosis: A case-control study in tea garden communities of Assam.

A high number of pulmonary tuberculosis (PTB) cases have been reported from tea garden communities of Assam. Till date, no molecular epidemiological study was performed to investigate the association of candidate gene(s) with the risk PTB in this region. The present case-control study was aimed to investigate the association of vitamin D receptor (VDR) gene polymorphisms and 22bp deletion in the promoter region of toll-like receptor 2 (TLR2) gene with the risk of PTB in tea garden communities of Assam. Genotyping of VDR polymorphisms and TLR2Δ22 (-196-174) gene was carried out for 169 PTB cases and 227 apparently healthy community controls using blood samples by PCR-RFLP followed by DNA sequencing. For association study, both univariate and multivariate logistic regression analyses were performed. This study has shown that BsmI and FokI polymorphisms of VDR gene significantly associated with an increased risk of PTB (AOR=3.58, 95% CI=1.64-7.80, P<.01 for B/b genotype of BsmI and AOR=2.44, 95% CI=1.40-4.24, P<.01 for F/f genotype of FokI polymorphism). No significant association of TaqI and ApaI polymorphism of VDR gene was found with the risk of PTB. Moreover, this study has revealed that person carrying deletion allele in their TLR2Δ22 (-196-174) gene is significantly associated with an increased risk of PTB having b/b or F/f genotypes in BsmI or FokI polymorphisms of VDR gene. This study has revealed that BsmI and FokI polymorphisms of VDR gene significantly associated with an increased risk of PTB.

Association of VDR gene TaqI polymorphism with the susceptibility to prostate cancer in Asian population evaluated by an updated systematic meta-analysis.

BackgroundThe vitamin D receptor (VDR) plays a key role in vitamin-mediated signaling pathway. Emerging evidence has suggested that the VDR polymorphism may contribute to the risk of prostate cancer (PCa). However, the existing results are not conclusive in Asian population.MethodsWe aim to evaluate the potential role of VDR polymorphisms on PCa of Asian population. PubMed, Scopus, Embase, Web of Science, Chinese National Knowledge Infrastructure, Wang Fang Data, and VIP Periodical were retrieved, and eligible studies (case–control or cohort study) meeting the inclusion criteria were evaluated through an updated meta-analysis using Stata13.0 software.ResultsA total of 1,363 cases and 2,101 controls obtained from 13 eligible publications were eventually included in this meta-analysis. Our results show that a significant association of VDR taq1 polymorphism with PCa risk, especially in the Japanese population. In the clinical stage-stratified analysis, the pooled results revealed no significant difference in genetic polymorphisms between the local stage and control groups, whereas there was increased frequency of T allele and TT genotype in the advanced tumor stage group compared with local tumor stage or control groups. Similarly, no significant difference was seen in Gleason <7 and control groups, but the T allele and TT genotype were significantly higher in the Gleason ≥7 group compared with Gleason <7 or control groups.ConclusionThe VDR TaqI polymorphism might be associated with PCa risk in Asian population, especially in the Japanese population. Also, PCa patients carrying the T allele or TT genotype were more likely to progress to advanced stage. These results suggest that VDR TaqI polymorphisms may be potential diagnostic biomarkers for PCa susceptibility.

Association of Vitamin D Receptor Gene TaqI, BsmI, FokI, and ApaI Polymorphisms and Susceptibility to Hallux Valgus in the Chinese Population

Previous studies have indicated that vitamin D receptor (VDR) TaqI, BsmI, FokI and ApaI gene polymorphisms are associated with the risk of skeletal malformations with inflammation. However, the potential association of VDR gene polymorphisms with the susceptibility to hallux valgus remains unclear. To clarify this association, we compared the genotypes of 228 patients with hallux valgus with those of 200 controls using the Multiplex SNaPshot system. The χ2 test was used to compare the allele and genotype frequencies between groups, and p ≤ .05 was considered statistically significant. The frequencies of the mutant allele C in TaqI (p = .036; odds ratio [OR] 1.57; 95% confidence interval [CI] 1.03-2.39) and mutant allele A in BsmI (p = .036; OR 1.33; 95% CI 1.02-1.74) were significantly greater in the patients than in the controls. In addition, after adjusting for sex and age, TaqI (p = .047; OR 1.61; 95% CI 1.00-2.58) and BsmI (p = .025; OR 1.67; 95% CI 1.06-2.61) were associated with the risk of hallux valgus through a dominant genetic model. A homozygous genetic model of BsmI was also significantly associated with the risk of hallux valgus (p = .033; OR 1.81; 95% CI 1.05-2.57). However, neither ApaI nor FokI were associated with increased susceptibility. To the best of our knowledge, we have reported for the first time that VDR gene TaqI and BsmI polymorphisms might contribute to the increased risk of hallux valgus in Chinese population.

Association between vitamin D receptor gene polymorphisms and pulmonary tuberculosis in a Mexican population

Background and aimsThe impact of host genetic variation in susceptibility of tuberculosis is well documented. The vitamin D receptor gene (VDR) is a transacting transcription factor which mediates innate immune response by enhancing the expression of several antimicrobial peptides, including cathelicidin. An association between VDR polymorphisms with tuberculosis (TB) has been investigated in different ethnic groups; however there are contradictions and inconsistencies in the results. The aim of this study was to evaluate the association between polymorphisms of functional VDR with the susceptibility to pulmonary tuberculosis in a Mexican population. MethodsA case–control study was performed in, 257 patients with pulmonary tuberculosis and 457 healthy controls recruited from: family medicine clinics of the Mexican Social Security Institute. The VDR gene polymorphisms Fok I (rs 2228570), BsmI (rs1544410), ApaI (rs7975232) and TaqI (rs731236) were genotyped by TaqMan assays. Statistical analysis was performed using: Epi Info V-7 and SNP Stats software. ResultsNo statistically significant associations were observed in genotype and haplotype distribution between BsmI, ApaI and TaqI polymorphisms and disease susceptibility. The CC genotype for the VDR gene FokI was significantly more frequent in patients than in controls (29.6% versus 17.5%, OR=1.97; 95% CI=1.37–2.8, PC=0.0004). Moreover, TT genotype was decreased in patients as compared to the control group (24.1% versus 34.8%, OR=0.59; 95% CI=0.42–0.84, PC=0.004). ConclusionTo our best knowledge, this is the first case-control study that finds an association between CC genotype of FokI SNP in the VDR gene with pulmonary tuberculosis in Mexican patients. However more validation studies should be performed to prove our conclusions.

The Impact of Five VDR Polymorphisms on Multiple Sclerosis Risk and Progression: a Case-Control and Genotype-Phenotype Study.

Vitamin D receptor polymorphisms have been the target of many studies focusing on multiple sclerosis. However, previously reported results have been inconclusive. The objective of this study was to investigate the association between five vitamin D receptor polymorphisms (EcoRV, FokI, ApaI, TaqI, and BsmI) and multiple sclerosis susceptibility and its course. The study was carried out as a case-control and genotype-phenotype study, consisted of 296 Czech multiple sclerosis patients and 135 healthy controls. Genotyping was carried out using polymerase chain reaction and restriction analysis. In multiple sclerosis men, allele and/or genotype distributions differed in EcoRV, TaqI, BsmI, and ApaI polymorphisms as compared to controls (EcoRV, pa = 0.02; Taq, pg = 0.02, pa = 0.02; BsmI, pg = 0.02, pa = 0.04; ApaI, pg = 0.008, pa = 0.005). In multiple sclerosis women, differences in the frequency of alleles and genotypes were found to be significant in ApaI (controls vs multiple sclerosis women: pg = 0.01, pa = 0.05). Conclusive results were observed between multiple sclerosis women in the case of EcoRV [differences in Expanded Disability Status Scale (p = 0.05); CT genotype was found to increase the risk of primary progressive multiple sclerosis 5.5 times (CT vs CC+TT pcorr = 0.01, sensitivity 0.833, specificity 0.525, power test 0.823)] and FokI [borderline difference in Multiple Sclerosis Severity Score (p = 0.05)]. Our results indicate that the distribution of investigated vitamin D receptor polymorphisms is a risk factor for multiple sclerosis susceptibility and progression in the Czech population. The association between disease risk and polymorphisms was found to be stronger in men. The association of disease progression with polymorphisms was observed only in women.

Association of vitamin D receptor gene polymorphism (TaqI and Apa1) with bone mineral density in North Indian postmenopausal women

Vitamin D receptor (VDR) gene has an important role as a candidate gene for the regulation of bone mass in osteoporosis. However, its association with bone mineral density (BMD) is controversial and has not been established in different ethnic populations. To enhance the understanding of VDR gene polymorphism in the context of BMD, we investigated the plausible genetic association of TaqI and ApaI polymorphism with BMD in North Indian postmenopausal women with osteoporosis.254 osteoporotic women (Age 55.82 ± 6.91) and 254 postmenopausal non osteoporotic women (Age 54.76 ± 6.26) were included in the study. VDR TaqI and ApaI polymorphism were determined by PCR (polymerase chain reaction) and RFLP (restriction fragment length polymorphism). BMD was assessed by dual energy X-ray absorptiometry (DXA) at the lumbar spine (L1-L4), hip, forearm and femoral neck. The average BMD with TT genotype was significantly lower at lumbar spine, hip and forearm. The Frequency of TT genotype and t allele was significantly high in osteoporotic women when compared with controls. The average BMD with Aa genotype was higher in ApaI. Furthermore, comparison of frequency distribution of genotype and allele for VDR ApaI between osteoporotic patients and controls did not show any significant difference. Our findings revealed that TaqI gene TT genotype was associated with low BMD in North Indian osteoporotic women. Moreover, TT genotype and t allele associated significantly with osteoporosis in postmenopausal women. Therefore, VDR TaqI gene is an important determinant of risk factor for osteoporosis.

Association of vitamin D receptor gene polymorphisms with serum 25(OH)D levels and metabolic syndrome in Thai population

Metabolic syndrome (MetS) increases the risk of developing cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM). The vitamin D receptor gene (VDR) polymorphisms have been found associated with MetS and serum 25(OH)D levels but these associations remain controversial. The aim of this study was to investigate the relationship between the VDR polymorphisms and MetS, metabolic components, and serum 25(OH)D levels within the Thai population. A case–control study included 237 participants with MetS according to the MetS diagnostic criteria of NCEP ATPIII and 376 controls. Anthropometric data, blood pressure, lipid profiles, serum 25 (OH)D, and fasting blood glucose were measured. VDR FokI, BsmI, TaqI, and Cdx2 polymorphisms were genotyped by using PCR-HRM. There were no significant differences in the frequencies of VDR genotypes and alleles between MetS and the control groups. VDR TaqI TT, and BsmI BB + Bb genotypes were associated with lower 25(OH)D levels (p < 0.05) in comparison to TaqI Tt, and BsmI bb genotypes in the MetS group, respectively. In addition, the VDR Cdx2 GG genotype was associated with higher WC compared with the AG genotype in all subjects (p < 0.05). Logistic regression analysis revealed that BB + Bb genotypes of the VDR BsmI had significantly increased the odds ratio (OR) of hypertriglyceridemia when compared with the bb genotype (OR 1.87; 95% CI 1.10–3.19, p = 0.022). In conclusion, VDR BsmI variant was associated with hypertriglyceridemia and may be predisposed to developing MetS. VDR TaqI and BsmI polymorphisms seems to influence serum 25(OH)D levels in MetS subjects, while Cdx2 polymorphism may influence WC in all subjects.

Association of vitamin D receptor gene TaqI, FokI and ApaI variants with arteriovenous fistula failure in hemodialysis patients.

We investigated the influence of the vitamin D receptor gene TaqI (rs731236), ApaI (rs7975232), and FokI (rs2228570) polymorphisms in arteriovenous fistula failure in hemodialysis patients. This study was carried out with 54 patients who experienced two or more fistula failures in the late period after arteriovenous fistula operation and 58 control patients with no history of arteriovenous fistula failure in 3 years or longer. The polymerase chain reaction-restriction fragment length polymorphism method was used to determine the vitamin D receptor TaqI, FokI, and ApaI polymorphisms. For vitamin D receptor gene TaqI and Fok1 polymorphisms, no significant association was found between the two groups ( p > 0.05). However, a statistically significant association was determined for ApaI polymorphism between the two groups ( p = 0.02). In patients, ApaI AA, AC, and CC genotype frequencies were found as 21 (38.9%), 32 (59.3%), and 1 (1.8%), respectively. However, genotype frequencies of AA, AC, and CC in the control group were 29 (50%), 22 (37.9%), and 7 (12.1%), respectively. In all three polymorphisms, no significant difference was found between the two groups in terms of allele frequencies ( p > 0.05). Vitamin D receptor ApaI AC genotype may be a possible cardiovascular risk factor for the development of arteriovenous fistula failure.

Influence of lifestyle characteristics and VDR polymorphisms as risk factors for intervertebral disc degeneration: a case\u2013control study

BackgroundIntervertebral disc degeneration (DD) is an important cause of low back pain and its precise aetiology is not fully understood, being attributed to cumulative environmental, biomechanical and genetic effects. The vitamin D plays a key role in regulation of calcium homeostasis and bone mineralization, exerting its biological activities by binding to a high-affinity receptor (VDR). Polymorphisms in VDR gene were previously associated with DD process, however with conflicting results. Here, we aimed to investigate the influence of lifestyle characteristics and VDR TaqI, BsmI, ApaI and FokI polymorphisms as risk factors for DD process.MethodsRetrospective case–control study involving 231 participants: 119 with confirmed DD and 112 healthy controls. Genotyping of VDR polymorphisms was performed by PCR–RFLP and real-time PCR using TaqMan methodology. All patients answered a questionnaire regarding lifestyle characteristics, such as educational level, pain localization, smoking habits, engagement of physical activity, postural and load weight at work and familial history of disc degeneration. The variables were compared between groups and adjusted by age and gender.ResultsThe case group was composed by 52% female and 48% male and the mean age was 40.0 years old, while in the control group 79% was female and 21% male and the mean age was 32.0 years old. Although gender distribution and mean age were different between groups, in the control group all participants were less than 45 years old and there was a prevalence of women in both groups. The factors that could be possibly associated to DD in the Brazilian population studied included smoking habits (26% in cases and 9% in controls, p = 0.003), lack of engagement in physical activity (observed in 77% of cases and 62% of controls, p = 0.018), and loading weight during work routine (58% in cases and 24% in controls, p ≤ 0.001). However, after adjusting by age and gender, only smoking habits remained associated to disc degeneration (p = 0.027). Considering the educational level, 35.2% of cases and 15.6% of controls had only the Elementary School, and 5.5% of DD group and 28.6% of control group had completed College (p = 0.025). In addition, educational level was directly associated to load weight at work (p = 0.012). Regarding VDR polymorphisms, no significant difference in genotype and allele frequencies between groups was observed. The haplotype analysis revealed that the combined wild-type alleles of TaqI, ApaI and FokI polymorphisms—TGT—was observed in a higher frequency in control group (p = 0.039).ConclusionThe findings suggested that smoking habits was a risk factor for disc degeneration in the population studied. Single analysis revealed no significant effects of VDR polymorphisms in disc degeneration process, while the combination of wild-type alleles of TaqI, ApaI and FokI polymorphisms, TGT haplotype, decreased the risk of the disease.