Evaluation of the correlation between serum levels of vitamin D and vitamin D receptor gene polymorphisms in an Egyptian population

The impact of genetic variants related to vitamin D and autoimmunity: A systematic review

Over the past few years, there has been a notable increment in scientific literature aimed at unraveling the genetic foundations of vitamin D signaling and its implications for susceptibility to autoimmunity, however, most of them address isolated diseases. Here, we conducted a systematic review of genetic variants related to vitamin D and autoimmune diseases and we discussed the current landscape of susceptibility and outcomes. Of 65 studies analyzed, most variants cited are in vitamin D binding protein (VDBP; rs2282679 GC gene), 25-hydroxylase (rs10751657 CYP2R1), 1α-hydroxylase (rs10877012, CYP27B1) and the nuclear hormone receptor superfamily [FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232), and TaqI (rs731236) in VDR gene]. Therefore, our findings confirmed the associations of several genetic variants of vitamin D signaling with a broad spectrum of autoimmune diseases/traits. In addition, given the low number of papers found with functional analysis, further studies to elucidate the real effect that the variants exert on Vitamin D signaling are recommended.

Vitamin D Receptor Gene Polymorphisms and Association with Vitiligo in Indonesian Population

Introduction

Vitiligo is an acquired depigmenting skin disorder due to the loss of melanocyte function in the epidermis and hair follicles. The pathogenesis of vitiligo is multifactorial, with genetics being a predisposing factor. Previous studies had varying results regarding whether or not polymorphisms of vitamin D receptor (VDR) gene are associated with the risk of vitiligo in specific populations. This study investigated the association between three frequently analyzed VDR gene polymorphisms (ApaI, BsmI, TaqI) and susceptibility to vitiligo in Indonesian population.

Methods

Thirty-four vitiligo patients and 34 age- and sex-matched healthy subjects aged ≥18 years old were recruited in the Dermatology and Venereology Outpatient Clinic of Dr. Hasan Sadikin General Hospital, Bandung, Indonesia. Genomic deoxyribonucleic acid (DNA) was extracted from the peripheral blood using a DNA isolation kit. VDR gene polymorphisms (ApaI, BsmI, and TaqI) were investigated using the polymerase chain reaction-restriction-fragment length polymorphism method. The differences of genotype distributions and allele frequencies were statistically compared between case and control groups using Chi-square test.

Results

VDR gene polymorphisms were identified in 68 participants, consisting of Aa (n = 14), aa (n = 20), Bb (n = 15), bb (n = 19), and TT (n = 34) genotypes in the case group. In the control group, Aa (n = 6), aa (n = 28), Bb (n = 17), bb (n = 17), and TT (n = 34) genotypes were identified. However, only subjects with ApaI Aa genotype polymorphism had a 3.267-fold increased risk of developing vitiligo.

Conclusion

This study showed that ApaI Aa genotype polymorphism of the VDR gene increases the risk of vitiligo in Indonesian population.

Serum vitamin D levels and vitamin D receptor gene ApaI and TaqI polymorphisms in patients with morphea: a case-control study

A uncommon inflammatory condition called morphea causes fibrosis in the skin and subcutaneous tissue. The key stages in the pathophysiology are vascular damage, immunological response, and fibrosis. Numerous research have examined the relationships between the immune system, fibrosis, and vitamin D, but the exact pathogenetic pathways of morphea remain poorly understood. The purpose of this study was to investigate serum 25(OH)D levels and the ApaI (rs7975232) and TaqI (rs731236) polymorphisms of the vitamin D receptor (VDR) in morphea patients. There were 48 age- and sex-matched controls and 41 morphea patients total. VDR polymorphisms were found using PCR tests and gel electrophoresis, and serum 25(OH)D levels were determined using liquid chromatography combined with tandem mass spectrometry (LC-MS/MS). The patient group consisted of 37 females (90.2%) and 4 males (9.8%). The patients' mean age was 38.68 ± 17.54 years. In terms of VDR ApaI and TaqI polymorphisms, there was no discernible difference between the patient and control groups. TaqI polymorphism heterozygosity was discovered in all patients with progressive disease, and this finding was statistically significant (p = 0.012). Patients' mean serum 25(OH)D levels were 16.98 ± 11.55 ng/mL, while those in the control group were 18.02 ± 14.30 ng/mL. VDR polymorphisms, vitamin D levels, disease subtype, age of onset, and responsiveness to treatment did not significantly correlate. In our research, we discovered that TaqI polymorphism may be related to the severity of the disease and that the polymorphisms of the VDR ApaI and TaqI were not associated with morphea susceptibility.

Evaluation of vitamin D receptor gene polymorphisms (ApaI and TaqI) as risk factors of vitiligo and predictors of response to narrowband UVB phototherapy

Vitiligo is acquired depigmentation due to multiple factors. Vitamin D in skin, through its receptors (VDR), regulates cell growth, differentiation, immune response and exerts both stimulatory and protective effects on melanocytes. The gene sequence encoding VDR has polymorphic forms such as ApaI and TaqI that may affect vitamin D actions. Narrowband ultraviolet B (NB-UVB) phototherapy became the mainstay of vitiligo treatment because of its efficacy and little side effects. The current work aimed at evaluating the possible association between VDR gene polymorphisms (TaqI and ApaI) and susceptibility of vitiligo and if they could be predictors of response to NB-UVB phototherapy in Egyptian vitiligo patients. 100 vitiligo patients indicated for NB-UVB phototherapy and 100 healthy age and sex matched controls were included. All participants were subjected to history taking, general and dermatological examinations, and VDR ApaI and TaqI gene polymorphisms analysis by PCR-RFLP. The patients received NB-UVB 3times per week for 6 months then revaluated. There was significant increase in Aa genotype of ApaI polymorphism in patients associated with significant increase in vitiligo activity. 66% of patient showed variable degrees of response to NB-UVB. The responders significantly had AA genotype of ApaI polymorphism. TaqI polymorphism showed nonsignificant effects on vitiligo susceptibility and response to NB-UVB. A allele of ApaI was significant independent predictor of NB-UVB phototherapy responders. VDR gene polymorphism (ApaI) may share in vitiligo pathogenesis and response to NB-UVB. Knowing the genetic background of the patient helps individualization of treatment to get better results.

Association between vitamin D receptor polymorphisms and vitiligo susceptibility: An updated meta-analysis

BACKGROUND

Vitamin D receptor (VDR) polymorphisms may play an important role in the vitiligo susceptibility. There have been many studies looking at the associations between VDR polymorphisms and vitiligo risk, but the conclusions are still up for debate.

AIM

This study aimed to determine whether polymorphisms in the VDR are associated to the susceptibility to vitiligo.

METHODS

Vitamin D receptor polymorphisms in vitiligo patients and controls were identified using PubMed/Medline and Embase databases. The relationships between the VDR ApaI, TaqI, BsmI, and TaqI polymorphisms and vitiligo were investigated using meta-analyses of all participants and Asian, Arab, European, and Latin American groups.

RESULTS

This meta-analysis included 13 papers with 2034 patients and 2771 controls. In all individuals, there was no link between vitiligo and the VDR ApaI A allele (OR = 0.889, 95% CI = 0.713-1.109, p = 0.298). However, in Asians (OR = 0.721, 95% CI = 0.553-0.940, p = 0.016) but not in Europeans or Arabs, there was a link between the VDR ApaI A allele and vitiligo. Utilizing recessive, dominant, and homozygote contrast models, a link between vitiligo and the VDR ApaI polymorphism was discovered in Asians. Meta-analysis of the VDR BsmI polymorphism showed a significant association between vitiligo and the B allele (OR = 0.812, 95% CI = 0.686-0.961, p = 0.015). In contrast, no connection between vitiligo and VDR polymorphisms was identified for TaqI and FokI polymorphisms.

CONCLUSION

In the Asian population, ApaI and BsmI polymorphisms in VDR have been correlated to vitiligo susceptibility. However, TaqI and FokI polymorphisms in VDR are not associated with vitiligo susceptibility in European, Asian, Arab, and Latin American populations.

Serum 25-Hydroxy Vitamin D Levels and Association of Vitamin D Receptor Gene Polymorphisms in Vitiligo

BACKGROUND

The role of vitamin D deficiency and vitamin D receptor (VDR) gene polymorphisms has been established in many autoimmune diseases, including vitiligo, but the result is still controversial.

OBJECTIVES

The aim of this study was to investigate the serum vitamin D levels in vitiligo patients and to compare the association of VDR gene polymorphisms in vitiligo patients and healthy controls.

METHODS

We collected the data of age, sex, serum 25-hydroxy vitamin D (25[OH]D) level, thyroid autoantibodies, disease duration, types of vitiligo, family history and the affected body surface area of vitiligo from 172 patients. And we analyzed the VDR gene polymorphisms in 130 vitiligo and 453 age-sex-matched control subjects.

RESULTS

The mean serum level of 25(OH)D in 172 vitiligo patients was 18.75 ± 0.60 ng/mL, which had no significant difference with a mean serum value of 25(OH)D in the Korean population. However, there were significant differences according to the duration of the disease and family history. Also, there were no significant differences in the genotypic and allelic distributions of 37 examined SNPs of VDR gene between vitiligo patients and healthy controls.

CONCLUSION

Serum level of 25(OH)D in vitiligo patients was not significantly different from the mean serum value of the Korean population. Also, there were no significant differences in the genotypic distributions of VDR gene between vitiligo patients and healthy controls.

Association of genetic variants of the vitamin D receptor gene with vitiligo in a tertiary care center in a Saudi population: a case-control study

BACKGROUND

Vitiligo is a common cutaneous disorder of the skin and hair caused by a systemic depigmentation disorder that affects 1% of the population or less due to its onset in early adulthood. Meta-analyses have documented a linkage between vitiligo and the vitamin D receptor (VDR) gene.

OBJECTIVE

Investigate the relationship between the ApaI, BsmI, FokI and TaqI genetic variants in the VDR gene with vitiligo in a Saudi population.

DESIGN

Case-control.

SETTING

Single tertiary care center.

PATIENT AND METHODS

The case-control study was carried out between January 2015-December 2015 in Saudi vitiligo patients and healthy controls. VDR genetic variants or polymorphisms (ApaI, BsmI, FokI and TaqI) were genotyped by polymerase chain reaction-restriction fragment length analysis followed by 3% agarose gel electrophoresis. Applicable statistical methods were used to assess relationships between vitiligo cases and controls.

MAIN OUTCOM MEASURE

Effect of genotype distribution among four single nucleotide polymorphisms.

SAMPLE SIZE

152 vitiligo (median [IQR] 23 [19] years) patients and 159 healthy controls (45 [28.5] years).

RESULTS

We found an association of vitiligo with ApaI and BsmI polymorphisms (P<.05). However, a decreased risk was noted in vitiligo patients with FokI and TaqI polymorphisms and in the diplotype and haplotype analysis within males and females. A positive association with vitiligo was observed in ACAC and AC (adjusted by gender) haplotypes (P<.05). The strongest linkage disequilibrium was observed between rs79785232 (ApaI) and rs731236 (TaqI) polymorphisms (r²=.83), followed by rs2228570 (FokI) and rs1544410 (BsmI) polymorphisms (r²=.53).

CONCLUSIONS

Our results confirm an association of vitiligo with ApaI and BsmI polymorphisms and fail to show an association in TaqI and FokI polymorphism with vitiligo. Additional studies need to be carried out in different Arab populations to determine whether the polymorphisms are present.

LIMITATIONS

Controls not age matched, small sample size, lack of biochemical parameters.

CONFLICT OF INTEREST

None.

Circulating Vitamin D Levels and Risk of Vitiligo: Evidence From Meta-Analysis and Two-Sample Mendelian Randomization

Background: The association between circulating vitamin D levels and risk of vitiligo was inconsistent among observational studies, and whether these observed associations were causal remained unclear. Therefore, we aimed to evaluate the effect of vitamin D on the risk of vitiigo using meta-analysis and Mendelian randomization (MR).

Methods: At the meta-analysis stage, literature search was performed in PubMed and Web of Science to identify eligible observational studies examining the association of circulating 25-hydroxyvitamin D [25(OH)D] or 25-hydroxyvitamin D₃ [25(OH)D₃] levels with risk of vitiligo up to April 30, 2021. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) of 25(OH)D and 25(OH)D₃ in patients with vitiligo relative to controls were pooled. Then at the MR stage, genetic instruments for circulating 25(OH)D (N = 120,618) and 25(OH)D₃ (N = 40,562) levels were selected from a meta-analysis of genome-wide association studies (GWAS) of European descent, and summary statistics of vitiligo were obtained from a meta-analysis of three GWASs including 4,680 cases and 39,586 controls. We used inverse-variance weighted (IVW) as main method, followed by weighted-median and likelihood-based methods. Pleiotropic and outlier variants were assessed by MR-Egger regression and MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO) test.

Results: In the meta-analysis, patients with vitiligo had a lower level of circulating 25(OH)D compared with controls [SMD = −1.40; 95% confidence interval (CI): −1.91, −0.89; P < 0.001], while no statistically significant difference of 25(OH)D₃ between vitiligo cases and controls was found (SMD = −0.63; 95% CI: −1.29, 0.04; P = 0.064). However, in the MR analyses, genetically predicted 25(OH)D [odds ratio (OR) = 0.93, 95% CI = 0.66–1.31, P = 0.66] and 25(OH)D₃ levels (OR = 0.95, 95% CI = 0.80–1.14, P = 0.60) had null associations with risk of vitiligo using the IVW method. Sensitivity analyses using alternative MR methods and instrumental variables (IV) sets obtained consistent results, and no evidence of pleiotropy or outliers was observed.

Conclusion: Our study provided no convincing evidence for a causal effect of 25(OH)D or 25(OH)D₃ levels on the risk of vitiligo. Further longitudinal and experimental studies, as well as functional studies are warranted to elucidate the role of vitamin D in the development of vitiligo.

Vitamin D status in Hashimoto's thyroiditis and its association with vitamin D receptor genetic variants

BACKGROUND

Hashimoto's thyroiditis (HT) is considered the predominant cause of hypothyroidism in iodine sufficient countries. The deficiency of 25-OH-vitamin D3 serum level and the variation of vitamin D receptor (VDR) gene were implicated in a number of autoimmune disorders. This study aimed to test the hypothesis linking between VDR FokI and BsmI variants and HT, in addition to explain their impact on 25-OH-vitamin D3 serum level.

MATERIALS AND METHODS

Cross sectional study included 160 hypothyroid subjects, 112 patients with HT and 48 hypothyroid non-HT controls. They were diagnosed based on anti-TPO Ab and or anti-TG Ab results. All cases were subjected to full history taking, thyroid ultrasound examination and a panel of assays (TSH, f.T3, f.T4, anti-TPO Ab, anti-TG Ab, calcium, alkaline phosphatase and phosphate). Serum 25-OH-vitamin D3 was assayed using HPLC-UV method. VDR variants (FokI and BsmI) were genotyped using real-time PCR.

RESULTS

FokI AA genotype was statistically higher in HT patients than control group (P value = 0.02) with subsequently higher serum 25-OH-vitamin D3 level in comparison to all other genotypes (P value = 0.039). Serum 25-OH-vitamin D3 level was statistically indifferent between HT and control group (P value = 0.223). A statistically significant increase in total thyroid volume was observed in HT group (P value = 0.002).

CONCLUSION

FokI AA genotype is more associated with HT in Egyptian patients compared to hypothyroid non-HT controls. Moreover, patients with FokI AA genotype have statistically higher levels of 25-OH-vitamin D3 suggesting VDR dysfunction even in patients expressing normal level of vitamin D.

Decreased circulatory levels of Vitamin D in Vitiligo: a meta-analysis

BACKGROUND

The serum Vitamin D status in patients with vitiligo is ambiguous when compared to controls. A systematic review and updated meta-analysis were conducted to evaluate the association between Vitamin D and vitiligo.

METHODS

Relevant studies were identified by searching PubMed and other databases. The random effects model was used to obtain standardized mean differences and pooled correlation coefficients. Meta-regression and sub-group analyses were conducted to explore heterogeneity. The presence of publication bias and the study robustness were tested using funnel plot and sensitivity analyses, respectively.

RESULTS

This meta-analysis finally included 31 studies. Compared with controls, vitiligo patients showed significantly decreased serum Vitamin D levels (standardized mean difference = -1.03; p < 0.0001). The sub-group analysis showed that vitiligo patients with indoor/urban work had a significantly lower Vitamin D level when compared to their outdoor/rural counterparts (standardized mean differences = -0.45; p = 0.03). The sensitivity analysis indicated that no single study had a significant influence on the overall outcome, suggesting the robustness of this meta-analysis.

STUDY LIMITATIONS

Varied sample sizes and heterogeneous study populations from different countries are the limitations of this study. However, the between-study heterogeneity has been addressed by the random-effects model with meta-regression and sensitivity analyses.

CONCLUSIONS

This meta-analysis showed significantly decreased Vitamin D level in vitiligo, and its association with indoor/outdoor type of work of vitiligo patients. This study highlights the need to assess Vitamin D status for improving its level in vitiligo.

Diagnostic and therapeutic implications of vitamin D deficiency in patients with warts: A case-controlled study

BACKGROUND

Cutaneous warts are frequent conditions that possess much challenge to treat.

OBJECTIVE

To verify the potential role of vitamin D in the pathogenesis of viral warts by measuring the serum levels of vitamin D in patients diagnosed with viral warts compared to healthy controls and to verify whether oral vitamin D supplementation of those vitamin D-deficient patients would result in wart clearance.

METHODS

To evaluate the serum vitamin D levels, the study recruited 80 subjects, including 40 patients diagnosed with viral warts and 40 age- and sex-matched healthy controls. All patients were subjected to detailed history taking and examination to detect duration and type of warts. Serum vitamin D levels were measured using ELISA.

RESULTS

Thirty-five percent of patients had sufficient vitamin D levels (54-90 nmol/L), and 40% of patients had insufficient levels (50-80 nmol/L), while 25% of them had deficient levels (<50 nmol/L). In healthy group, 30% had sufficient levels, and 45% had insufficient levels, while 25% had deficient levels. There was an insignificantly lower serum level of vitamin D as well as an insignificantly deficient vitamin D status among patients compared to healthy controls.

CONCLUSION

Vitamin D serum levels appear to be lower among viral wart patients, and oral supplementation studies need to be more intensely investigated before elucidating its role; if any, in wart clearance.

Impact of vitamin D receptor gene polymorphisms on vitiligo susceptibility and clinical features in a Southeastern European Caucasian population

An association of vitamin D receptor (VDR) polymorphisms and vitiligo has been suggested. However, previous studies have reported contradictory results while including limited data among Caucasians. The aim of this single-center study was to evaluate the effect of three common VDR gene polymorphisms (FokI, TaqI and BsmI) on suscep-tibility and clinical aspects of vitiligo in a Southeastern European Caucasian population. A total of 110 unrelated vitiligo cases and 509 general population controls were enrolled from October 2018 to November 2019. Genomic DNA was extracted from whole blood after de-identification and anonymization of the samples and genotyped for the selected VDR polymorphisms by the qPCR (melting curve analysis). Subgroup analysis by clinical features among subsets of patients indicated that, compared to subjects with the FokI TT genotype or T allele, carriers of the FokI CC genotype or C allele exhibited significantly decreased risk of developing vitiligo before the age of 30 [TT vs. CC: odds ratio (OR)=0.286, 95% confidence interval (CI): 0.083-0.984, P=0.041; T vs. C: OR=0.545, 95% CI: 0.313-0.948, P=0.031]. Intra-patient analysis also revealed that, compared to T allele, the presence of TaqI C allele was adversely associated with the incidence of concurrent leukotrichia (T vs. C: OR=1.874, 95% CI: 1.018-3.451, P=0.042). Comparisons between the case and control groups showed no evidence to support an association between susceptibility to vitiligo and the VDR BsmI, TaqI, and FokI polymorphisms in this cohort. Thus, the studied VDR polymorphisms might indirectly impact the clinical course and treatment decision-making despite their lack of association with vitiligo per se. Further research with larger sample sizes, especially across Caucasian individuals, should be performed to confirm these findings.

Catalase but not vitamin D receptor gene polymorphisms are associated with nonsegmental vitiligo in Northwestern Mexicans

BACKGROUND

Vitiligo is an acquired pigmentation disorder characterized by melanocyte loss via autoimmune mechanisms triggered by oxidative stress. Gene polymorphisms in antioxidant enzymes and immunomodulators such as catalase (CAT) and vitamin D receptor (VDR), respectively, have been linked to vitiligo in European and Asian populations. Our aim was to evaluate the role of CAT and VDR gene polymorphisms as well as CAT and vitamin D in nonsegmental vitiligo in Northwestern Mexicans.

METHODS

A total of 357 subjects, 173 nonsegmental vitiligo patients and 184 age-gender matched healthy controls, were genotyped by PCR-restriction fragment length polymorphism. CAT activity was determined in 39 patients and in 39 controls and vitamin D (VitD) levels in 35 individuals per group.

RESULTS

CAT 419 C/T gene polymorphism was not informative, -89 A/T was associated with risk (P = 0.02), and 389 C/T conferred protection against vitiligo along with AT haplotype (P < 0.01 in both cases). VDR BsmI, ApaI, and TaqI gene polymorphisms were not associated with vitiligo, but BsmI was more prevalent in patients with Koebner phenomenon (P = 0.02). Serum CAT activity and VitD levels were lower in patients than in controls, but they showed no association with any vitiligo clinical characteristics neither with their gene polymorphisms.

CONCLUSIONS

Our results suggest a role for CAT gene polymorphisms in vitiligo susceptibility in the Mexican population and a lack of association with VDR gene polymorphisms.

Role of serum 25-hydroxyvitamin D levels and vitamin D receptor gene polymorphisms in patients with rosacea: a case-control study

BACKGROUND

Vitamin D has significant effects on the immune system and thereby on the pathogenesis of rosacea. However, there is a lack of information on the vitamin D status and vitamin D receptors (VDRs) of patients with rosacea.

AIM

To evaluate the role of vitamin D in rosacea susceptibility.

METHODS

A case-control study was conducted, enrolling patients with rosacea and healthy controls (HCs). Five VDR gene single nucleotide polymorphisms (SNPs) (Cdx2, FokI, ApaI, BsmI and TaqI) and serum 25-hydroxyvitamin D₃ [25(OH)D₃ ] levels were compared between patients and HCs.

RESULTS

The study enrolled 60 patients (M/F: 14/46) and 60 age- and sex-matched HCs (M/F: 14/46). Age (mean ± SD) was 48 ± 11 years for both groups. The serum 25(OH)D₃ levels (median ± interquartile range) were higher in patients with rosacea (12.9 ± 6.8 ng/mL) than in HCs (10.5 ± 3.7 ng/mL) (P < 0.001). Subjects with high serum 25(OH)D₃ levels had a 1.36-fold increased risk of rosacea (95% CI 1.17-1.58). Heterozygous and mutant ApaI polymorphisms increased rosacea risk by 5.26-fold (95% CI 1.51-18.35) and 3.69-fold (95% CI 1.19-11.48), respectively, whereas mutant TaqI polymorphisms decreased the risk by 4.69 times (95% CI 1.37-16.67). Heterozygosity for Cdx2 alleles increased rosacea risk, whereas wildtype ApaI and mutant TaqI alleles decreased it.

CONCLUSIONS

The present study suggests that an increase in vitamin D levels may contribute to the development of rosacea. ApaI and TaqI polymorphisms, and heterozygous Cdx2, wildtype ApaI and mutant TaqI alleles were significantly associated with rosacea. These results indicate a possible role of vitamin D and VDR pathways in the pathogenesis of rosacea, although causality could not be assessed.

Vitamin D receptor gene polymorphism, serum 25-hydroxyvitamin D levels, and risk of vitiligo: A meta-analysis

OBJECTIVES

To explore the relationship among the vitamin D receptor (VDR) gene polymorphisms, serum 25-hydroxyvitamin D levels, and vitiligo.

METHODS

Databases including PubMed, Cochrane Library, Ovid, Web of Science, CNKI, SinoMed, and Wanfang Data were systematically searched. The association was assessed using odds ratios (ORs), standard mean difference (SMD), and 95% confidence intervals (CIs). The statistical tests were performed using Review Manager 5.3.3.

RESULTS

We identified a total of 17 studies. The relationship between VDR gene polymorphisms (BsmI, ApaI, TaqI, and FokI), serum 25 (OH)D levels, and incidence of vitiligo was investigated. The results of this meta-analysis showed that the dominant genetic model (CC+AC vs AA, P = .007, OR = 1.41, 95% CI = 1.10-1.80), recessive genetic model (CC vs AC+AA, P = .01, OR = 4.10, 95% CI = 1.36-12.35), and allelic contrast model (C vs A, P = .005, OR = 1.87, 95% CI = 1.21-2.90) of VDR Apal locus increased the risk of vitiligo, and BsmI, TaqI, and FokI loci and the risk of vitiligo have no obvious correlation. Serum 25 (OH)D deficiency was positively associated with the incidence of vitiligo (P < .0001, SMD = -0.94, 95% CI = -1.39, -0.48).

CONCLUSION

This meta-analysis revealed that VDR Apal polymorphism increased the susceptibility risk of vitiligo, and there is a positive correlation between serum 25 (OH)D deficiency and the incidence of vitiligo.