Association between a single nucleotide polymorphism in MTHFR gene and polycystic ovary syndrome

Folate and Vitamin B12 Levels in Chilean Women with PCOS and Their Association with Metabolic Outcomes

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects women of reproductive age. Many women with PCOS have been found to have an unbalanced diet and deficiencies in essential nutrients. This study aimed to assess the levels of folate and vitamin B12 (B12) and their relationship with metabolic factors in women with PCOS. Anthropometric, clinical, and genetic analyses were conducted to evaluate markers related to one-carbon metabolism in women with PCOS and in a control group. The PCOS group had a higher BMI and HOMA-IR (1.7 vs. 3.1; p < 0.0001). HDL cholesterol levels were 23% lower and triglyceride levels were 74% higher in women with PCOS. Although there were no significant differences in folate and B12 levels between the PCOS and control groups, over 60% of women with PCOS had low B12 levels (<300 pg/mL) and high homocysteine levels. In addition, the MTHFR A1298C and C677T polymorphisms were not associated with PCOS. Moreover, erythrocyte folate levels were positively correlated with fasting glucose, triglycerides, and free androgen index, and negatively correlated with SHBG and LH levels. These results suggest that B vitamins may be associated with the metabolic phenotype in PCOS. This study emphasizes the potential link between folate, vitamin B12, and metabolic and hormonal outcomes in women with PCOS.

Cholecalciferol and metformin protect against lipopolysaccharide-induced endothelial dysfunction and senescence by modulating sirtuin-1 and protein arginine methyltransferase-1

Endothelial cell activation through nuclear factor-kappa-B (NFkB) and mitogen-activated protein kinases leads to increased biosynthesis of pro-inflammatory mediators, cellular injury and vascular inflammation under lipopolysaccharide (LPS) exposure. Recent studies report that LPS up-regulated global methyltransferase activity. In this study, we observed that a combination treatment with metformin (MET) and cholecalciferol (VD) blocked the LPS-induced S-adenosylmethionine (SAM)-dependent methyltransferase (SDM) activity in Eahy926 cells. We found that LPS challenge (i) increased arginine methylation through up-regulated protein arginine methyltransferase-1 (PRMT1) mRNA, intracellular concentrations of asymmetric dimethylarginine (ADMA) and homocysteine (HCY); (ii) up-regulated cell senescence through mitigated sirtuin-1 (SIRT1) mRNA, nicotinamide adenine dinucleotide (NAD+) concentration, telomerase activity and total antioxidant capacity; and (iii) lead to endothelial dysfunction through compromised nitric oxide (NOx) production. However, these LPS-mediated cellular events in Eahy926 cells were restored by the synergistic effect of MET and VD. Taken together, this study identified that the dual compound effect inhibits LPS-induced protein arginine methylation, endothelial senescence and dysfunction through the components of epigenetic machinery, SIRT1 and PRMT1, which is a previously unidentified function of the test compounds. In silico results identified the presence of vitamin D response element (VDRE) sequence on PRMT1 suggesting that VDR could regulate PRMT1 gene expression. Further characterization of the cellular events associated with the dual compound challenge, using gene silencing approach or adenoviral constructs for SIRT1 and/or PRMT1 under inflammatory stress, could identify therapeutic strategies to address the endothelial consequences in vascular inflammation-mediated atherosclerosis.

Potential environmental toxicant exposure, metabolizing gene variants and risk of PCOS-A systematic review

Exposure of environmental toxicants such as potentially toxic metals and pesticides have largely been attributed to produce adverse effects on general women's health and to be more precise on the reproductive system. In order to explore exposure of toxicants and metabolizing gene variants as risk factor for polycystic ovarian syndrome (PCOS), literature search was carried out using the databases PubMed, Central Cochrane Library, Google Scholar, Science Direct with appropriate keywords upto 6 December 2020. While most of the studies indicate higher serum Cu concentration and lower concentration of Mn as risk factor, studies also report presence of higher pesticide concentration in PCOS women. Genes such as MTHFR, CYPs participate in the metabolism of toxicants and may show different response due to underlying genetic variants. Thus, toxicant exposure are to some extent responsible for the pathogenesis of syndrome through oxidative stress and endocrine disruption, but the susceptibility may vary due to the underlying genetic polymorphism of the exposed population.

Methylenetetrahydrofolate reductase gene polymorphisms in the risk of polycystic ovary syndrome and ovarian cancer

Polymorphisms of methylenetetrahydrofolate reductase (MTHFR) in hormone metabolism pathways might cause metabolic disturbances and contribute to the development of polycystic ovary syndrome (PCOS) and ovarian cancer, but the published studies were inconsistent. The aim of the present study was to evaluate the MTHFR C677T (rs1801133) and A1298C (rs1801131) gene polymorphisms in the risk of PCOS and ovarian cancer by meta-analysis. A comprehensive electronic search was conducted in databases for studies published from 1995 to 2020. The pooled ORs were calculated by Revman 5.2 software. Twenty-nine articles including 45 case–control studies were included. We found that MTHFR C677T polymorphisms were correlated with elevated PCOS risk (TT vs. CT+CC: OR = 1.41, 95%CI = 1.20–1.67; TT+CT vs. CC: OR = 1.54, 95%CI = 1.07–2.22; CT vs. CC+TT: OR = 1.18, 95%CI 1.04–1.33; TT vs. CC: OR = 1.47, 95%CI = 1.03–2.11; T vs. C: OR = 1.25, 95%CI = 1.06–1.47), which were more obvious in Middle Eastern subgroup. MTHFR A1298C polymorphisms were also associated with overall PCOS susceptibility (CC vs. AC+AA: OR = 2.55, 95% CI = 1.61–4.03; CC+AC vs. AA: OR = 1.84, 95%CI = 1.04–3.28; CC vs. AA: OR = 2.66, 95%CI = 1.68–4.22; C vs. A: OR = 1.67, 95%CI = 1.03–2.71), which were mainly reflected in Asian subjects. For ovarian cancer, MTHFR C677T polymorphisms were only related with elevated ovarian cancer risk in Asian population, while no significant association was found for A1298C polymorphisms. This meta-analysis suggested that MTHFR C677T and MTHFR A1298C polymorphisms were correlated with elevated PCOS risk. MTHFR C667T only posed a higher risk for ovarian cancer in Asians instead of other populations, while MTHFR A1298C polymorphisms were not related to ovarian cancer risk. Further studies are needed to validate the conclusion.

The Insulin-like Growth Factor-1 (G>A) and 5,10-methylenetetrahydrofolate Reductase (C677T) Gene Variants and the Serum Levels of Insulin-like Growth Factor-1, Insulin, and Homeostasis Model Assessment in Patients with Acne Vulgaris

Background & Objective

To find an association between gene variants of insulin-like growth factor-1 (IGF-1) and 5,10-methylenetetrahydrofolate reductase (MTHFR) with the risk of acne vulgaris (AV).

Methods

In a case-control study, we investigated 150 AV patients and 148 healthy individuals (aged 18-25 years) for the IGF-1 G>A and MTHFR C677T polymorphisms, as well as the serum levels of IGF-1, insulin, and the homeostasis model assessment of insulin resistance (HOMA-IR). The serum biochemical parameters and the genotypes of IGF-1 G>A and MTHFR C677T were detected by using appropriate kits and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods, respectively.

Results

The frequencies of IGF-1 and the MTHFR polymorphisms were not significantly different comparing patients and controls. The serum level of IGF-1 was 179.8±72.8 µg/L in AV patients compared to 164.6±63.7 µg/L in controls (P=0.056). The serum level of insulin in female patients was significantly higher than controls. The HOMA was 3.54±5.6 in patients compared to 1.16±1.4 (P<0.001) in controls. Significantly higher levels of fasting blood sugar (FBS), total cholesterol, and low-density lipoprotein-cholesterol (LDL-C) were detected in female patients than controls. However, the level of estradiol was significantly lower in female patients than in controls. In females, the presence of the MTHFR T allele was associated with significantly higher levels of FBS and LDL-C, as well as a significantly lower level of estradiol compared to those carriers of the C allele.

Conclusion

We found the absence of an association between IGF-1 and MTHFR polymorphisms with the risk of AV. However, increased insulin, IGF-1, and HOMA levels in AV patients indicated the effect of insulin and insulin resistance in the risk of AV and its severity.

Significant association between methylenetetrahydrofolate reductase gene C677T polymorphism with polycystic ovary syndrome risk: A meta-analysis update

The methylenetetrahydrofolate reductase (MTHFR) may play a pathological role in polycystic ovary syndrome (PCOS). However, the conclusions of published reports on the relationship between the MTHFR C677T polymorphism and PCOS risk remain controversial.To derive a more precise estimation we performed a metaanalysis based on 22 studies that together included 2405 cases and 2419 controls. PubMed, EMBASE, WanFang and the Chinese National Knowledge Infrastructure databases were used to retrieve articles up to up to October 28, 2019. The crude odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated to evaluate the association.Metaanalysis results showed a significant association between the MTHFR C677T polymorphism and PCOS risk in 3 genetic models (allele model: OR = 1.40, 95% CI = 1.27-1.53; dominant model: OR = 1.47, 95% CI = 1.17-1.85); homozygous model: OR = 1.90, 95% CI = 1.55-2.32). Moreover, significant associations were observed when stratified by ethnicity, source of controls, etiology, and genotype methods.This metaanalysis suggests that the T-allele of the MTHFR C677T polymorphism is associated with an increased risk of PCOS, especially in Asians further studies with larger population sizes are needed to confirm these results.

Can the genetic polymorphisms of the folate metabolism have an influence in the polycystic ovary syndrome?

OBJECTIVE

To investigate the association of the genetic variants of the folate metabolism genes (MTHFR C677T; MTHFR A1298C; MTR A2756G; MTRR A66G and RFC-1 A80G) with the development of polycystic ovary syndrome (PCOS).

SUBJECTS AND METHODS

This study included 203 women (99 women with PCOS and 104 controls). The genotyping was performed by PCR-RFLP. Chi-squared test and multiple logistic regression were used in the statistical analysis. Haplotype analysis was conducted using the SNPstat program. The results were presented in odds ratio (OR) and confidence interval of 95% (CI-95%), with a significance level of 5% (p ≤ 0.05).

RESULTS

The genotypic distribution of the RFC-1 A80G polymorphism showed significant difference between the two groups, showing that the heterozygous genotype (AG genotype) was most frequent in controls. The polymorphic homozygous (GG genotype) of MTRR A66G polymorphism were most frequent in controls. The T-C haplotype MTHFR C677T and A1298C polymorphisms were more frequent in the control group (OR = 0.19; CI 95% - 0.04 to 0.93 e p = 0.042). The multivariate analysis evidenced that family history of PCOS was more frequent in the PCOS group (OR = 3.29; CI 95% - 1.48 to 7.31; p = 0.003).

CONCLUSION

In our casuistry, the polymorphic homozygous of MTRR A66G polymorphism gene and heterozygous of RFC-1 A80G polymorphism gene, the haplotype T-C C677T and A1298C polymorphisms of MTHFR gene, can be associated with protective factors for the disease.

Genetic polymorphism of methylenetetrahydrofolate reductase is associated with insulin resistance in Egyptian women with polycystic ovary syndrome

BACKGROUND

A common polymorphism (677C to T; Ala to Val) in the methylenetetrahydrofolate reductase (MTHFR) gene is associated with decreased specific MTHFR activity and elevation of homocysteine. The present study aimed to investigate the association between a single nucleotide polymorphism (SNP) in the MTHFR 677C>T gene and insulin resistance in women with polycystic ovary syndrome (PCOS).

METHODS

Two-hundred patients with PCOS were included in this case-control study: 100 patients with insulin resistance and 100 patients without insulin resistance were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis.

RESULTS

The TT genotype for the MTHFR 677C>T polymorphism was significantly more frequent in PCOS patients with insulin resistance than in PCOS patients without insulin resistance (19% versus 6%, p = 0.002), whereas there was no significant difference between both groups for CT and there was a statistically significant increase in the T allele in PCOS patients with insulin resistance compared to PCOS patients without insulin resistance (p = 0.002, odds ratio = 1.95 and 95% confidence interval = 1. 29-2.93). Regarding the relationship between MTHFR 677C>T genotypes and the characteristics of insulin resistance in PCOS patients, we found that there was no significant difference in age, waist-hip ratio and total testosterone between the different genotypes of the MTHFR 677C>T polymorphism. The mean values for body mass index and the Homeostatic Model Assessment of Insulin Resistance were significantly higher in the TT genotype of MTHFR 677C>T compared to the CC genotype in PCOS patients with insulin resistance (p < 0.001).

CONCLUSIONS

We have demonstrated an association of the MTHFR 677C>T gene polymorphism with insulin resistance in Egyptian women with PCOS.

Potential genetic polymorphisms predicting polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a heterogenous endocrine disorder with typical symptoms of oligomenorrhoea, hyperandrogenism, hirsutism, obesity, insulin resistance and increased risk of type 2 diabetes mellitus. Extensive evidence indicates that PCOS is a genetic disease and numerous biochemical pathways have been linked with its pathogenesis. A number of genes from these pathways have been investigated, which include those involved with steroid hormone biosynthesis and metabolism, action of gonadotropin and gonadal hormones, folliculogenesis, obesity and energy regulation, insulin secretion and action and many others. In this review, we summarize the historical and recent findings in genetic polymorphisms of PCOS from the relevant publications and outline some genetic polymorphisms that are potentially associated with the risk of PCOS. This information could uncover candidate genes associating with PCOS, which will be valuable for the development of novel diagnostic and treatment platforms for PCOS patients.

Methylenetetrahydrofolate reductase C677T polymorphism and the risks of polycystic ovary syndrome: an updated meta-analysis of 14 studies

Some studies have reported an association between the Methylenetetrahydrofolate reductase (MTHFR) C667T genetic variant and risk of polycystic ovary syndrome (PCOS), although the results remain controversial. A systematic search was conducted on PubMed, Web of Science, EMBASE, Ovid, Chinese National Knowledge Databases and WanFang databases with relevant keywords. Fourteen studies of sixteen distinct populations involving 1478 PCOS cases and used to conduct a meta-analysis. The T allele was not significantly associated with increased risk of PCOS [OR: 1.08; 95% CI: 0.96–1.21]. In the stratified analysis by ethnicity, the T allele significantly increases risks for the Asian [OR = 1.31; 95% CI: 1.09–1.58] population. No significant associations were detected for the Middle Eastern population [OR = 1.26; 95% CI: 0.96–1.67] and the T allele was found to be protective in the Caucasian population [OR = 0.82; 95% CI: 0.68–0.99]. In conclusion, this meta-analysis suggests that MTHFR C667T variant can increase, decrease, or have no effect on the risks of PCOS depending on the ethnicity.

Single nucleotide polymorphisms in the TGF-β1 gene are associated with polycystic ovary syndrome susceptibility and characteristics: a study in Korean women

PURPOSE

Although many hypotheses regarding the pathogenesis of polycystic ovary syndrome (PCOS) have been generated, genetic studies have not identified specific genes that play a role in PCOS etiopathogenesis. This study aimed to investigate the relationship between TGF-β1 gene polymorphism and PCOS in Koreans.

METHOD

A total of 51 Korean women with PCOS and 69 healthy women were enrolled. We analyzed 4 single nucleotide polymorphisms (SNPs) of the TGF-β1 gene (rs11466313, rs1800469, rs2317130, and rs4803457). We also analyzed laboratory measurements, such as free testosterone, glucose, and cholesterol.

RESULTS

The frequencies of rs1800469T allele negativity, rs4803457T allele negativity, the rs1800469CC genotype, and the rs4803457CC genotype showed positive associations with PCOS (P = 0.003, P = 0.027, P = 0.009, and P=0.031, respectively), whereas the haplotypes rs1800469C-rs4803457T and rs1800469T-rs4803457T showed negative associations with PCOS. A strong protective effect of the "rs1800469CT-rs4803457TT" combination (OR = 0.09) and a strong risk effect of "rs1800469CC-rs4803457CC" (OR = 6.23) for PCOS were observed. The rs1800469C/T and rs2317130C/T SNPs exhibited associations with several laboratory measurements with various levels of significance.

CONCLUSION

The results demonstrated an association of TGF-β1 gene polymorphisms with the development and/or characteristics of PCOS in the Korean population.

Is MTHFR 677 C>T Polymorphism Clinically Important in Polycystic Ovarian Syndrome (PCOS)? A Case-Control Study, Meta-Analysis and Trial Sequential Analysis

BACKGROUND

Optimum efficiency of the folate pathway is considered essential for adequate ovarian function. 677 C>T substitution in the 5, 10-methylene tertrahydrofolatereductase (MTHFR) gene compromises activity of the MTHFR enzyme by about 50%. The significance of correlation between 677C>T substitution and PCOS remains dubious due to the low power of published studies.

METHODS AND RESULTS

We analyzed MTHFR 677 C>T site in ethnically two different PCOS case-control groups (total 261 cases and 256 controls) from India. The data analysis revealed a lack of association between this polymorphism and PCOS [OR = 1.11 (95%CI = 0.71-1.72), P = 0.66]. Group-wise analysis on the basis of ethnicity also revealed no association in any of the ethnic groups [Indo-Europeans, P = 1; Dravidians, P = 0.70]. Homocysteine levels did not differ significantly between cases (15.51 μmol/L, SD = 2.89) and controls (15.89 μmol/L, SD = 2.23). We also undertook a meta-analysis on 960 cases and 1028 controls, which suggested a significant association of the substitution with PCOS in the dominant model of analysis (OR = 1.47 (95%CI = 1.04-2.09), P = 0.032]. Trial sequential analysis corroborated findings of the traditional meta-analysis. However, we found that the conclusions of meta-analysis were strongly influenced by studies that deviated from the Hardy Weinberg equilibrium. A careful investigation of each study and a trial sequential analysis suggested that 677 C>T substitution holds no clinical significance in PCOS in most of the populations.

CONCLUSION

In conclusion, MTHFR 677 C>T polymorphism does not affect PCOS risk in India. The association seen in the meta-analysis is due to an outlier study and studies showing deviation from the Hardy Weinberg equilibrium.

Apolipoprotein A-IV as a novel gene associated with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic disorder, affecting 6-10% of women of reproductive age. The etiology remains poorly understood. To investigate the differentially expressed proteins from PCOS patients versus healthy women, the protein expression in follicular fluid was analyzed using two-dimensional electrophoresis (2-DE). Since follicular fluid contains a number of secretory proteins required for oocyte fertilization and follicle maturation, it is possible that follicular fluid can be used as a provisional source for identifying pivotal proteins associated with PCOS. In this study, six overexpressed proteins [kininogen 1, cytokeratin 9, antithrombin, fibrinogen γ-chain, apolipoprotein A-IV (apoA-IV) precursor and α-1-B-glycoprotein (A1BG)] in follicular fluids from PCOS patients were identified with matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS) and nano LC-MS/MS. Western blot analysis confirmed that the protein expression levels of apoA-IV precursor and A1BG were increased in follicular fluid from PCOS patients compared with those from normal controls. The analysis of protein expression for other proteins revealed individual variation. These results facilitate the understanding of the molecular mechanisms of PCOS and provide candidate biomarkers for the development of diagnostic and therapeutic tools.

MTHFR C677T polymorphism is associated with hyperlipidemia in women with polycystic ovary syndrome

CONTEXT

Women with polycystic ovary syndrome (PCOS) are prone for coronary artery disease (CAD), and hyperhomocysteinemia is an independent risk factor for CAD. MTHFR deficiency is the most common cause of hyperhomocysteinemia, thereby provoking a possible association between PCOS and MTHFR C677T polymorphism.

AIMS

The aim of this study was to investigate an association of MTHFR C677T polymorphism with PCOS.

SETTINGS AND DESIGN

92 women with PCOS (Rotterdam criteria) and 95 age-matched controls were compared with respect to MTHFR C677T polymorphism. The 2 genotypes (CC and CT) obtained were compared with clinical and laboratory parameters in women with PCOS.

MATERIALS AND METHODS

In a case-control study, clinical, biochemical, hormonal and genetic analysis (PCR-RFLP of peripheral leucocytes) was carried out on all women with PCOS as well as controls.

STATISTICAL ANALYSIS

Student "t" test for quantitative and Chi-square test for nominal variables was used. For estimation of risk, odds ratio and 95% confidence interval were calculated.

RESULTS

The odds ratio of bearing a heterozygous genotype (CT) was 1.32 in women with PCOS as compared to controls (P = 0.48). No homozygous mutation (TT) was found in the study population. Serum cholesterol was more in heterozygous (CT) genotype (215.48 ± 25.56 mg/dl) as compared to normal (CC) genotype (203.29 ± 16.35 mg/dl) in women with PCOS (P = 0.01). Similarly, serum triglyceride was more in heterozygous (CT) genotype (95.86 ± 37.34 mg/dl) as compared to normal (CC) genotype (82.36 ± 20.88 mg/dl) in women with PCOS (P = 0.04).

CONCLUSIONS

Although not statistically significant, there is a slightly higher prevalence of heterozygous (CT) genotype in women with PCOS. MTHFR C677T polymorphism when present may confer an increased susceptibility to develop hyperlipidemia in women with PCOS. More prospective studies are needed to confirm whether this hyperlipidemia due to MTHFR C677T polymorphism clinically manifests into CAD in long term in women with PCOS.

The promoter -1031(T/C) polymorphism in tumor necrosis factor-alpha associated with polycystic ovary syndrome

BACKGROUND

A tumor necrosis factor-alpha is a multifunctional pro-inflammation cytokine, which has been considered as one of pathogenic factors for various diseases. The promoter -1031(T/C) polymorphism in the tumor necrosis factor-alpha gene was reported that it plays a part in reproduction-related diseases. Among these, polycystic ovary syndrome (PCOS) is known to be a common gynecological disease of women in reproductive age women. Here, we performed a comparative study of -1031(T/C) polymorphism of TNF-alpha gene with PCOS in a Korean population.

METHODS

The -1031(T/C) polymorphism of TNF-alpha gene was analyzed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in a total of 217 PCOS patients and 144 matched female controls of healthy women. And statistical analysis was performed using HapAnalyzer. X2 test and logistic regression were utilized analyze the association between two groups. A p-value under 0.05 was considered statistically significant.

RESULTS

The genotype and allelic frequencies were in Hardy-Weinberg equilibrium (HWE). There was strong association between the -1031(T/C) polymorphism in the promoter region of TNF-alpha gene and PCOS (p-value = 0.0003, odd ratio (OR) = 2.53). In addition, the frequency of C allele was significantly higher in PCOS patients compared with controls. Sequence analyses also showed the -1031(T/C) polymorphism of TNF-alpha gene.

CONCLUSION

This is the first study on the -1031(T/C) polymorphism of TNF-alpha gene in PCOS. We concluded that the -1031(T/C) polymorphism of TNF-alpha gene is associated with PCOS in a Korean population. Therefore, it is possible that it may be considered as a clinical biomarker to diagnose for PCOS, and is helpful in understanding the etiology for the pathogenesis of PCOS.

Association of angiotensin converting enzyme (ACE) gene I/D polymorphism and polycystic ovary syndrome (PCOS)

This study was conducted in Turkish patients with polycystic ovary syndrome to determine the frequency of I/D polymorphism genotypes of angiotensin converting enzyme gene, and to examine the role of this polymorphism in polycystic ovary syndrome development. Genomic DNA obtained from 200 persons (100 patients with polycystic ovary syndrome and 100 healthy controls) was used in the study. DNA was multiplied by polymerase chain reaction using I and D allele-specific primers. Polymerase chain reaction products were assessed with a charge coupled device (CCD) camera by being exposed to 2% agarose gel electrophoresis. There was statistically significant difference between the groups with respect to genotype distribution (p<0.001). The D allele frequency was indicated as 68% and I allele was as 32% in the patients, whereas it was 51.5-48.5% respectively in the control group. As a result of our study we may assert that angiotensin converting enzyme gene I/D polymorphism DD genotype should be considered as a genetic marker in polycystic ovary syndrome development in this Turkish study population.

Association of polycystic ovarian syndrome with human leukocyte antigen polymorphism in Korean women

Although several studies have demonstrated the genetic contribution to polycystic ovarian syndrome (PCOS), the cause of this syndrome remains unclear. The aim of this study was to elucidate the relationship between human leukocyte antigen (HLA) systems and PCOS in Koreans. We compared the HLA-A, B and DRB1 genotype distribution of 52 PCOS patients and 67 healthy Korean women. In addition, we investigated the association of HLA with free-testosterone level. HLA-A*11, A*31 and B*54 showed increased phenotype frequencies (PFs) in PCOS women compared to controls (p = 0.032, OR 2.79; p = 0.019, OR 6.05; p = 0.002, OR 6.40). HLA-DRB1*15 showed negative correlations with the free-testosterone concentration both in total subjects and PCOS patients (p = 0.024 and p = 0.008). The results of the study suggest mild associations of HLA alleles with pathophysiology of PCOS and/or testosterone production in PCOS. Further investigation in a large number of subjects, including subdivision and multi-population studies, will need to be conducted to prove the consistent or variable association in PCOS.