Association of aromatase (CYP 19) gene variation with features of hyperandrogenism in two populations of young women

The Pathophysiological Mechanism and Clinical Treatment of Polycystic Ovary Syndrome: A Molecular and Cellular Review of the Literature

Polycystic ovary syndrome (PCOS) is a prevalent metabolic disorder among women of reproductive age, characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovaries. The pathogenesis of PCOS involves a complex interplay of genetic and environmental factors, including insulin resistance (IR) and resultant hyperinsulinemia. Insulin receptors, primarily in skeletal muscle, liver, and adipose tissue, activate downstream signaling pathways like PI3K-AKT and MAPK-ERK upon binding. These pathways regulate glucose uptake, storage, and lipid metabolism. Genome-wide association studies (GWASs) have identified several candidate genes related to steroidogenesis and insulin signaling. Environmental factors such as endocrine-disrupting chemicals and lifestyle choices also exacerbate PCOS traits. Other than lifestyle modification and surgical intervention, management strategies for PCOS can be achieved by using pharmacological treatments like antiandrogens, metformin, thiazolidinediones, aromatase inhibitor, and ovulation drugs to improve insulin sensitivity and ovulatory function, as well as combined oral contraceptives with or without cyproterone to resume menstrual regularity. Despite the complex pathophysiology and significant economic burden of PCOS, a comprehensive understanding of its molecular and cellular mechanisms is crucial for developing effective public health policies and treatment strategies. Nevertheless, many unknown aspects of PCOS, including detailed mechanisms of actions, along with the safety and effectiveness for the treatment, warrant further investigation.

Delineating the role of single-nucleotide polymorphism of CYP19 gene on aromatase activity in South Indian women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome is a common multifactorial endocrinopathy disorder affecting 5-15% of reproductive women worldwide. The CYP19 gene encodes key enzyme aromatase involved in androgen-to-estrogen conversion which plays a crucial role in the pathophysiology of the syndrome. Very few studies have been done in the Indian population; hence, we investigated whether CYP19 gene rs2414096 SNP is associated with PCOS and hyperandrogenism susceptibility in Karnataka women.

METHODS

Three-hundred subjects including 150 PCOS and 150 age-matched controls were involved in the current case-control study. Sex hormones and biochemical estimation were performed by ELISA. Sanger sequencing and PCR-RFLP were used to genotype the SNP rs2414096. Genotypic-phenotypic association was studied. Statistical analysis was performed.

RESULTS

The GG genotype was more common in patients, while the GA genotype was more common in control women. LH/FSH was significantly increased in GG genotype in PCOS when compared with AA and GA genotypes. Variations of CYP19 rs2414096 were not statistically significant with PCOS.

CONCLUSION

CYP19 rs2414096 polymorphism was not associated with PCOS; however, the homozygous wild GG genotype may exhibit reduced aromatase activity with subsequent hyperandrogenism implicating endocrine abnormalities.

In-Silico Investigation of Effects of Single-Nucleotide Polymorphisms in PCOS-Associated CYP11A1 Gene on Mutated Proteins

Polycystic ovary syndrome (PCOS) is a reproductive disorder with multiple etiologies, mainly characterized by the excess production of androgens. It is equally contributed to by genes and environment. The CYP11A1 gene is imperative for steroidogenesis, so any dysregulation or mutation in this gene can lead to PCOS pathogenesis. Therefore, nucleotide diversity in this gene can be helpful in spotting the likelihood of developing PCOS. The present study was initiated to investigate the effect of single nucleotide polymorphisms in human CYP11A1 gene on different attributes of encoded mutated proteins, i.e., sub-cellular localization, ontology, half-life, isoelectric point, instability index, aliphatic index, extinction coefficient, 3-D and 2-D structures, and transmembrane topology. For this purpose, initially coding sequence (CDS) and single nucleotide polymorphisms (SNPs) were retrieved for the desired gene from Ensembl followed by translation of CDS using EXPASY tool. The protein sequence obtained was subjected to different tools including CELLO2GO, ProtParam, PHYRE2, I-Mutant, SIFT, and PolyPhen. It was found that out of seventy-eight SNPs analyzed in this project, seventeen mutations, i.e., rs750026801 in exon 1, rs776056840, rs779154292 and rs1217014229 in exon 2, rs549043326 in exon 3, rs755186597 in exon 4, rs1224774813, rs757299093 and rs1555425667 in exon 5, rs1454328072 in exon 7, rs762412759 and rs755975808 in exon 8, and rs754610565, rs779413653, rs765916701, rs1368450780, and rs747901197 in exon 9 considerably altered the structure, sub-cellular localization, and physicochemical characteristics of mutated proteins. Among the fifty-nine missense SNPs documented in present study, fifty-five and fifty-three were found to be deleterious according to SIFT and PolyPhen tools, respectively. Forty-nine missense mutations were analyzed to have a decreasing effect on the stability of mutant proteins. Hence, these genetic variants can serve as potential biomarkers in human females for determining the probability of being predisposed to PCOS.

The role of polymorphism in various potential genes on polycystic ovary syndrome susceptibility and pathogenesis

Polycystic ovary syndrome (PCOS) is the most common endocrinopathies affecting the early reproductive age in women, whose pathophysiology perplexes many researchers till today. This syndrome is classically categorized by hyperandrogenism and/or hyperandrogenemia, menstrual and ovulatory dysfunction, bulky multi follicular ovaries on Ultrasonography (USG), and metabolic abnormalities such as hyperinsulinemia, dyslipidemia, obesity. The etiopathogenesis of PCOS is not fully elucidated, but it seems that the hypothalamus-pituitary-ovarian axis, ovarian, and/or adrenal androgen secretion may contribute to developing the syndrome. Infertility and poor reproductive health in women's lives are highly associated with elevated levels of androgens. Studies with ovarian theca cells taken from PCOS women have demonstrated increased androgen production due to augmented ovarian steroidogenesis attributed to mainly altered expression of critical enzymes (Cytochrome P450 enzymes: CYP17, CYP21, CYP19, CYP11A) in the steroid hormone biosynthesis pathway. Despite the heterogeneity of PCOS, candidate gene studies are the widely used technique to delineate the genetic variants and analyze for the correlation of androgen biosynthesis pathway and those affecting the secretion or action of insulin with PCOS etiology. Linkage and association studies have predicted the relationship between genetic variants and PCOS risk among families or populations. Several genes have been proposed as playing a role in the etiopathogenesis of PCOS, and the presence of mutations and/or polymorphisms has been discovered, which suggests that PCOS has a vital heritable component. The following review summarizes the influence of polymorphisms in crucial genes of the steroidogenesis pathway leading to intraovarian hyperandrogenism which can result in PCOS.

Differences in expression of genes related to steroidgenesis in abdominal subcutaneous adipose tissue of pregnant women with and without PCOS; a case control study

BACKGROUND

It was reported that steroid-related gene expressions in the adipose tissue (AT) of women differ between women affected with polycystic ovary syndrome (PCOS) and non-PCOS. Although association between PCOS in mother and offspring's health is a crucial issue, there are few studies focusing on AT of pregnant women suffering from PCOS. Our objectives were to determine the differences between mRNA expression levels of key steroid-converting enzymes in abdominal subcutaneous AT of pregnant women afflicted with PCOS and non-PCOS.

METHODS

Twelve pregnant women with PCOS (case) and thirty six non-PCOS pregnant women (control) (1:3 ratio; age- and BMI-matched) undergoing cesarean section were enrolled for the present study. Expressions of fifteen genes related to steriodogenesis in abdominal subcutaneous AT were investigated using quantitative real-time PCR.

RESULTS

No significant differences were detected with respect to age, BMI (prior pregnancy and at delivery day), gestational period and parity among pregnant women with PCOS and non-PCOS. Most of the sex steroid-converting genes except 17β-Hydroxysteroid dehydrogenases2 (17BHSD2), were highly expressed on the day of delivery in subcutaneous AT. Women with PCOS showed significantly higher mRNA levels of steroidgenic acute regulator (STAR; P < 0.001), cytochrome P450 monooxygenase (CYP11A1; P < 0.05), 17α-hydroxylase (CYP17A1; P < 0.05), and 11β-Hydroxysteroid dehydrogenase (11BHSD1 and 11BHSD2; P < 0.05). The expression of steroid 21-hydroxylase (CYP21) in non-PCOS was fourfold higher than those of women with PCOS (P < 0.001). There were no significant differences between relative expression of aromatase cytochrome P450 (CYP19A1), 3β-hydroxysteroid dehydrogenase (3BHSD1 and 3BHSD2), and 17BHSD family (1, 3, 5, 7, and 12) between the two groups.

CONCLUSION

The expression levels of genes related to sex steroids metabolism were similar to age-matched and BMI- matched pregnant non-PCOS and pregnant women with PCOS at delivery day. However, the alterations in gene expressions involved in glucocorticoids and mineralocorticoids metabolism were shown. It is necessary to point out that further studies regarding functional activity are required. More attention should be given to AT of pregnant women with PCOS that was previously ignored.

Impact of rs2414096 polymorphism of CYP19 gene on susceptibility of polycystic ovary syndrome and hyperandrogenism in Kashmiri women

Polycystic ovary syndrome (PCOS) is the most common reproductive endocrine disorder in pre-menopausal women having complex pathophysiology. Several candidate genes have been shown to have association with PCOS. CYP19 gene encodes a key steroidogenic enzyme involved in conversion of androgens into estrogens. Previous studies have reported contradictory results with regard to association of SNP rs2414096 in CYP19 gene with PCOS and hyperandrogenism in different ethnic populations. Present study was aimed to investigate the impact of SNP rs2414096 polymorphism of CYP19 gene on susceptibility of PCOS and hyperandrogenism in Kashmiri women. Further we also studied the genotypic-phenotypic association for various clinical and biochemical parameters of this polymorphism. Case control study. 394 PCOS cases diagnosed on the basis of Rotterdam criteria and age matched 306 healthy women. We found a significant differences in genotypic frequency (χ² = 18.91, p < 0.05) as well as allele frequency (OR 0.63, CI 0.51–0.78, χ² = 17.66, p < 0.05) between PCOS women and controls. The genotype–phenotype correlation analysis showed a significant difference in FG score (p = 0.047) and alopecia (p = 0.045) between the three genotypes. Also, the androgen excess markers like DHEAS (p < 0.001), Androstenedione (p < 0.001), Testosterone (p < 0.001) and FAI (p = 0.005) were significantly elevated in GG genotype and showed a significant difference in additive model in PCOS women. rs2414096 polymorphism of CYP19 gene is associated with the risk of PCOS as well as with clinical and biochemical markers of hyperandrogenism, hence suggesting its role in clinical manifestations of PCOS in Kashmiri women.

Association of the CYP17 and CYP19 gene polymorphisms in women with polycystic ovary syndrome from Punjab, Pakistan

BACKGROUND

Polycystic ovarian syndrome (PCOS) is considered the most common multifactorial endocrinopathy. Genetic factors play an essential role in the pathogenesis of PCOS. CYP 17 enzyme is responsible for androgenesis, while CYP 19 enzyme works for androgen conversion into aromatic estrogen. Several studies have reported their association with PCOS. This study was aimed to investigate the association of cytochrome P450c17α gene (CYP17) 5'-untranslated region MspA1/(rs743572) genetic polymorphism and rs2414096 of cytochrome P450 or aromatase (CYP19) gene polymorphism with the susceptibility to PCOS in reproductive-age women from Punjab, Pakistan.

METHODS

We performed a case-control association study was conducted, including 204 PCOS patients and 100 controls. Genotyping of SNP rs2414096 (CYP 19 gene) and P450c17α gene (CYP17) 5'-untranslated region MspA1 was performed on genomic DNA using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Statistical analysis was performed to find out the association of phenotypic and genotypic characters in etiopathology of PCOS.

RESULTS

The genotype distribution for CYP 17 5'-UTR MspA1 (TT, TC, CC) revealed that the frequency of genotype TC is significantly higher in PCOS patients (54.9%) vs. controls (OR 4.97, 95% CI 2.75-8.33, p<.001) (12%). The genotype distribution for CYP 19 (GG, GA, AA) showed significantly higher frequency of GA (58.%) and AA (23.5%) in patients as compared to cases (18% and 8%, respectively) (OR 5.49, 95% CI 3.61-8.34, p<.001). Body mass index (BMI), waist, hip, infertility and family history of infertility, PCOS, diabetes, and hypertension were found significantly associated with PCOS. CYP 19 genotypes were found significantly associated with PCOS patients having paraclinical traits of infertility and family history of infertility, while CYP 17 genotypes showed no significant association with any paraclinical traits in PCOS patients.

CONCLUSIONS

This is the first study on PCOS genotypes from Pakistan and results suggest that CYP 17 5'-UTR MspA1 (rs743572) (genotype TC) and CYP 19 gene (rs2414096) (genotype GA) polymorphisms are significantly associated with susceptibility to PCOS in Pakistani women having the traits of infertility and family history of hypertension.

Association between single nucleotide polymorphism of the CYP19A1 and ESR2 genes and endometriosis

PURPOSE

Endometriosis is a frequent gynaecological condition, both in Poland and in the world. The development of this disease is supported by hormonal, immunological and environmental factors. During the recent years, a particular attention has been focused on the genetic polymorphisms which may be of particular significance for the increased incidence rates of endometriosis. According to literature data, Oestrogen Receptor 2 (ESR2) and Cytochrome P450 Family 19 Subfamily A Member 1 (CYP19A1) genes may be accounted to the potential risk factors of infertility associated with endometriosis. The reported research was aimed to evaluate the association between single nucleotide polymorphisms (SNPs) rs17179740 of ESR2 and rs2899470 of CYP19A1 genes and the incidence of endometriosis.

METHODS

The study material included blood specimens, collected from patients (n = 200) with endometriosis. Blood samples from age-matched, endometriosis-free women (n = 200) served as control. The High-Resolution Melter (HRM) technique was applied for polymorphism analysis.

RESULTS

Regarding rs2899470 polymorphism TT homozygotes was significantly more prevalent among the patients with endometriosis than in the controls (OR 2.19; p = 0.04). In case of rs17179740, GG homozygotes, as well as AG-AA genotypes, were significantly more prevalent among the endometriosis patients (OR 2.48, p = 0.04 and OR 2.36, p = 0.04, respectively).

CONCLUSION

Summing up, the investigated polymorphisms of ESR2 and CYP19A1 gene are associated with the observed incidence of endometriosis.

CYP19 gene rs2414096 variant and differential genetic risk of polycystic ovary syndrome: a systematic review and meta-analysis

Previously, many studies investigated the association between CYP19 rs2414096(G > A) and susceptibility to develop PCOS. However, results had been inconsistent. Therefore, our systematic review and meta-analysis aimed to identify the association between CYP19 rs2414096 and PCOS risk. Methods: A systematic literature search was done from database PubMed, Google Scholar, Science Direct, and Cochrane Library up to July 15 2020 and statistical analysis was performed by RevMan5.3. Results: A total of seven studies comprised of 1414 PCOS cases and 1276 controls were included in the current meta-analysis. The pooled analysis showed that overall, there is a significant association between CYP19 rs2414096(G > A) and risk of PCOS (OR = 0.74, 95% CI= 0.62-0.88, p = .0008). In dominant model, GG + AG vs GG and recessive genetic model AA vs AG + GG found a significant association (OR = 1.60,95% CI = 1.10-2.31, p = .01; OR = 0.65,95% CI = 0.45-0.93, p = .02) respectively which indicates that GG phenotype might be risk factor for PCOS development. In stratified subgroup analysis, there was significant association between CYP19 rs2414096 polymorphism and PCOS risk for non-Indian population only while no association was found with Indian population. Conclusion: Present meta-analysis studies indicate that CYP19 rs2414096 is associated with PCOS risk and important in pathogenesis of PCOS for many populations but for Indian population more studies are required as Indian population comprises of various subpopulations genetically isolated since long.

The Genetic Background of Endometriosis: Can ESR2 and CYP19A1 Genes Be a Potential Risk Factor for Its Development?

Endometriosis is defined as the presence of endometrial foci, localized beyond their primary site, i.e., the uterine cavity. The etiology of this disease is rather complex. Its development is supported by hormonal, immunological, and environmental factors. During recent years, particular attention has been focused on the genetic mechanisms that may be of particular significance for the increased incidence rates of endometriosis. According to most recent studies, ESR2 and CYP19A1 genes may account for the potential risk factors of infertility associated with endometriosis. The paper presents a thorough review of the latest reports and data concerning the genetic background of the risk for endometriosis development.

CYP19A1 Gene Expression in Patients with Polycystic Ovarian Syndrome

Context:

Polycystic ovarian syndrome (PCOS) is a common endocrine system disorder among the women of reproductive age, yet the etiology of PCOS remains unclear. Infertility in females with PCOS can be caused by anovulation, high luteinizing hormone levels, and hyperandrogenism.

Aims:

This research analyzed the role of the aromatase gene (CYP19A1) in PCOS pathogenesis.

Settings and Design:

This study used an observational, cross-sectional design.

Subjects and Methods:

A total of 110 research participants (55 PCOS patients and 55 non-PCOS patients) were included in the study.

Statistical Analysis Used:

A real-time quantitative polymerase chain reaction was used to analyze the mRNA expression for aromatase in granulosa cells.

Results:

The relative expression of aromatase mRNA is lower in women with PCOS compared to those without PCOS (P < 0.05). Relative expression of CYP19A1 (aromatase) mRNA in PCOS group was 0.38 ± 0.25, whereas in non-PCOS group was 1.00 ± 0.00. The decline in aromatase activity contributes to an increase in testosterone level. This condition has a role in hyperandrogenism which is a typical characteristic of PCOS women. Granulosa cells in polycystic ovary undergo disturbance in the development and cannot respond to follicle-stimulating hormone (FSH) stimulation. Lack of stimulation of FSH causes induction inadequacy to aromatase enzyme activity in the aromatization process. The decline in FSH activity is caused by various factors that are associated with typical characteristics of PCOS.

Conclusions:

There is a decrease in the relative expression rate of granulosa cells’ aromatase mRNA in women with PCOS compared to the non-PCOS.

Recent advances in mammalian reproductive biology

Reproductive biology is a uniquely important topic since it is about germ cells, which are central for transmitting genetic information from generation to generation. In this review, we discuss recent advances in mammalian germ cell development, including preimplantation development, fetal germ cell development and postnatal development of oocytes and sperm. We also discuss the etiologies of female and male infertility and describe the emerging technologies for studying reproductive biology such as gene editing and single-cell technologies.

Hyperandrogenism in polycystic ovarian syndrome and role of CYP gene variants: a review

Background

Polycystic ovary syndrome (PCOS) is a multifactorial endocrine disorder characterized by anovulation, hyperandrogenism, and polycystic ovarian morphology. The pathophysiology of PCOS is not clear; however, disturbance in hypothalamic-pituitary-ovarian axis and abnormal steroidogenesis along with genetic and environmental factors act as main contributors to this disorder.

Main text

Hyperandrogenism, the hallmark feature of PCOS, is clinically manifested as hirsutism, acne, and alopecia. Excessive androgen production by ovaries as well as from adrenals contributes to hyperandrogenism. Abnormalities in the neuroendocrine system like increased pulse frequency of gonadotropin-releasing hormone, stimulating the pituitary for excessive production of luteinizing hormone than that of follicle-stimulating hormone is seen in PCOS women. Excess LH stimulates ovarian androgen production, whereas a relative deficit in FSH impairs follicular development. The imbalance in LH: FSH causes proliferation of ovarian theca cells leading to increased steroidogenesis, and ultimately leading to hyperandrogenism in PCOS women. Various genetic factors have been shown to be associated with abnormal steroidogenesis. CYP genes involved in steroidogenesis play an important role in androgen production and are considered as key players in hyperandrogenism in PCOS.

Conclusion

Polymorphisms in CYP genes can aggravate the hyperandrogenic phenotype in women with PCOS by either upregulating or downregulating their expression, thus increasing androgens further. However, this hypothesis needs to be validated by further studies.

Pathophysiological mechanisms of gonadotropins- and steroid hormones-related genes in etiology of polycystic ovary syndrome

OBJECTIVES

Polycystic ovary syndrome (PCOS) is an endocrinopathy in women, which, unlike its impact on fertility and health of women, there is no clear understanding about the causal mechanisms of this pathogenesis. The aim of this review paper is to investigate the pathophysiological pathways affecting the PCOS etiology, based on functions of gonadotropins- and steroid hormones-related genes.

MATERIALS AND METHODS

Due to different hormonal and metabolic signs of this complex disorder, different hypotheses are mentioned about etiology of this syndrome. Because of the heterogeneity of the reasons given for this syndrome and the spread of the effective genes in its pathophysiology, most of genes affected by sex-related hormonal imbalances are examined for discriminative diagnosis. For this purpose, published articles and reviews dealing with genetic evaluation of PCOS in women in peer-reviewed journals in PubMed and Google Scholar databases were included in this review.

RESULTS

In previous studies, it has been well demonstrated that PCOS in some individuals have a genetic origin. Pathophysiological functions of genes are primarily responsible for the synthesis of proteins that have role in PCOS before hyperandrogenism including GnRHR, FSHβ, FSHR, LHCGR, CYP19A1, HSD17B, AR and SHBG, and their effects in PCOS of human have been confirmed.

CONCLUSION

Hormonal imbalances are the first reason mentioned in PCOS etiology, and usually characterized with menstrual irregularities in PCOS women. Hyperandrogenism and gonadotropin secretion disorders are shown in PCOS condition, which are related to steroidogenesis pathways and hypothalamic-pituitary-ovarian axis disturbances, respectively.

Association of PON1 gene polymorphisms with polycystic ovarian syndrome risk: a meta-analysis of case-control studies

PURPOSE

Evidences showed that paraoxonase 1 (PON1) gene polymorphism has an impact on women's susceptibility to polycystic ovarian syndrome (PCOS) by influencing the expression and activity of PON1. However, the effects of three PON1 polymorphisms (- 108 C>T, L55M and Q192R) on the incidence of PCOS have generated inconsistent results. Here, we conducted a meta-analysis to investigate the association between PON1 polymorphisms and PCOS risk.

METHODS

All eligible trials were identified via systematic searches of multiple literature databases. Outcome data were synthesized by using crude odds ratio with 95% confidence interval. Heterogeneity was assessed with the I² test. Publication bias and subgroup analyses were also performed.

RESULTS

A total of 2449 cases and 1977 controls from nine studies were selected for analysis. The pooled results showed a significant association between PCOS risk and PON1 - 108 C/T polymorphism in the following genetic models [allelic, 0.72 (0.56-0.92); homozygote, 0.51 (0.32-0.82); heterozygote, 0.44 (0.25-0.78); and dominant 0.47 (0.29-0.77)]. For the PON1 192 Q/R polymorphism, a significant relationship was found in the allelic model [0.62 (0.41-0.93)] and recessive model [0.61 (0.37-0.98)]. PCOS risk was also linked to PON1 L55M polymorphism in the heterozygote model [0.62 (0.39-0.98)] and dominant model [0.63 (0.41-0.96)].

CONCLUSIONS

Our study has shown that PON1 - 108 C/T polymorphism might be associated with increased risk of PCOS under the allelic, homozygote, heterozygote, and dominant models. Additionally, PON1 192 Q/R and L55M polymorphisms were significantly related only in the allelic and recessive model, and in the heterozygote and dominant model, respectively.

The role of DENND1A and CYP19A1 gene variants in individual susceptibility to obesity in Turkish population-a preliminary study

Single nucleotide polymorphisms (SNPs), the most common genetic variations in human genome, can manage the predisposition of certain complex diseases or situations such as obesity. Genetic polymorphisms also play an important role as they can impact a population's susceptibility to being overweight or obese and developing related chronic complications such as hypertension, coronary heart disease, diabetes and cancer. The present study comprised of 193 unrelated healthy volunteers (120 females and 73 males) with Turkish origin. Only female adolescents (n = 110) were divided into 2 categories according to their BMI values as overweight (BMI ≥ 25) and normal (18.5 < BMI < 25) according to WHO classification. Genomic DNA was isolated from venous blood samples and genotyping of DENND1A rs10818854 and CYP19A1 rs2414096 variants was performed on Roche Light Cycler 2.0 Real-Time PCR platform. Serum hormone levels were analyzed by Electrochemiluminescent Immunoassay (ECLIA; Roche diagnostics). The genotype distributions were consistent with the Hardy-Weinberg equilibrium for both SNPs in the studied population (p > 0.05). The genotype distribution of DENND1A rs10818854 was determined for the first time in Turkish population and the variant allele frequency was found as 0.095. According to reduced sex hormone-binding globulin levels and increased free androgen index in the present study, obesity was linked with hyperandrogenism in female subjects. Both polymorphisms were investigated as potential genetic susceptibility markers for obesity and neither DENND1A nor CYP19A1 showed any associations.

Genetic association study from North India to analyze association of CYP19A1 and CYP17A1 with polycystic ovary syndrome

PURPOSE

Polycystic ovary syndrome (PCOS) is a complex multifactorial endocrine disorder affecting approximately 5-10% of women of reproductive age. Affected women have menstrual disturbances due to anovulation, infertility, and hyperandrogenism. Ovarian androgen overproduction is the key physiopathologic feature of PCOS. A number of genes encoding major enzymes of the androgen metabolic pathways, such as HSD17B6, CYP19A1, CYP11A1, CYP17A1, and INSR, have been examined. Very few studies have been done in North India. There is an increasing prevalence of PCOS in women in Punjab and it is the leading cause of female infertility. In view of the strong evidence implicating the importance of CYP19A1 and CYP17A1 in androgen metabolic pathways, we investigated the association of rs700519, rs2414096, and rs743572 (- 34T>C) polymorphisms on susceptibility of developing PCOS, in North India.

METHODS

A total of 500 subjects (women of reproductive age) including 250 PCOS cases and 250 healthy age-matched controls were included in the present study. DNA was extracted from venous blood for all samples, and association analysis for rs2414096, rs700519, and rs743572 was done by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Lipid profile was done using a biochemical analyzer and body mass index (BMI) was measured for all cases. Statistical analysis was performed.

RESULTS

Significant association of - 34T>C polymorphism of CYP17A1 was found with PCOS (p = 0.0005). BMI was statistically different between PCOS cases and controls (p = 0.000). Triglycerides were high in PCOS women. Variations of CYP19A1 were not statistically significant with PCOS.

CONCLUSIONS

These data suggest that - 34T>C polymorphism in CYP17A1 is associated with PCOS in North India. No polymorphism of CYP19A1 was found to be associated.

Genetic Variants Associated with Hyperandrogenemia in PCOS Pathophysiology

Polycystic ovary syndrome is a multifactorial endocrine disorder whose pathophysiology baffles many researchers till today. This syndrome is typically characterized by anovulatory cycles and infertility, altered gonadotropin levels, obesity, and bulky multifollicular ovaries on ultrasound. Hyperandrogenism and insulin resistance are hallmark features of its complex pathophysiology. Hyperandrogenemia is a salient feature of PCOS and a major contributor to cosmetic anomalies including hirsutism, acne, and male pattern alopecia in affected women. Increased androgen levels may be intrinsic or aggravated by preexisting insulin resistance in women with PCOS. Studies have reported augmented ovarian steroidogenesis patterns attributed mainly to theca cell hypertrophy and altered expression of key enzymes in the steroidogenic pathway. Candidate gene studies have been performed in order to delineate the association of polymorphisms in genes, which encode enzymes in the intricate cascade of steroidogenesis or modulate the levels and action of circulating androgens, with risk of PCOS development and its related traits. However, inconsistent findings have impacted the emergence of a unanimously accepted genetic marker for PCOS susceptibility. In the current review, we have summarized the influence of polymorphisms in important androgen related genes in governing genetic predisposition to PCOS and its related metabolic and reproductive traits.

Which origin for polycystic ovaries syndrome: Genetic, environmental or both?

Polycystic ovaries syndrome (PCOS), the most common female endocrine disorder, affects 7-10% of women of childbearing age. It includes ovarian hyperandrogenism, impaired follicular maturation, anovulation and subfertility. Insulin resistance, although present in most cases, is not necessary for diagnosis. It increases hyperandrogenism and long-term metabolic, cardiovascular and oncological risks. The origin of hyperandrogenism and hyperinsulinemia has a genetic component, as demonstrated by familial aggregation studies and recent identification of associated genomic variants, conferring a particular susceptibility to the syndrome. However, experimental and epidemiological evidences also support a developmental origin via a deleterious foetal environment, concerning the endocrine status (foetal hyperandrogenism), the nutritional level (intrauterine growth retardation), or the toxicological exposure (endocrine disruptors). Epigenetic changes recently reported in the literature as associated with PCOS, enhance this hypothesis of foetal reprogramming of the future adult ovarian function by environmental factors. Better characterisation of these genetic, epigenetic, or environmental factors, could lead to earlier prevention and more efficient treatments.

Alcohol-related breast cancer in postmenopausal women - effect of CYP19A1, PPARG and PPARGC1A polymorphisms on female sex-hormone levels and interaction with alcohol consumption and NSAID usage in a nested case-control study and a randomised controlled trial

Background

Alcohol consumption is associated with increased risk of breast cancer (BC), and the underlying mechanism is thought to be sex-hormone driven. In vitro and observational studies suggest a mechanism involving peroxisome proliferator-activated receptor gamma (PPARγ) in a complex with peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α) and interaction with aromatase (encoded by CYP19A1). Use of non-steroidal anti-inflammatory drugs (NSAID) may also affect circulating sex-hormone levels by modifying PPARγ activity.

Methods

In the present study we assessed whether genetic variation in CYP19A1 is associated with risk of BC in a case-control study group nested within the Danish “Diet, Cancer and Health” cohort (n_cases = 687 and n_controls = 687) and searched for gene-gene interaction between CYP19A1 and PPARGC1A, and CYP19A1 and PPARG, and gene-alcohol and gene-NSAID interactions. Association between the CYP19A1 polymorphisms and hormone levels was also examined among 339 non-HRT users. Incidence rate ratios were calculated based on Cox’ proportional hazards model. Furthermore, we performed a pilot randomised controlled trial to determine the effect of the PPARG Pro¹²Ala polymorphism and the PPARγ stimulator Ibuprofen on sex-hormone levels following alcohol intake in postmenopausal women (n = 25) using linear regression.

Results

Genetic variations in CYP19A1 were associated with hormone levels (estrone: P_rs11070844 = 0.009, estrone sulphate: P_rs11070844 = 0.01, P_rs749292 = 0.004, P_rs1062033 = 0.007 and P_rs10519297 = 0.03, and sex hormone-binding globulin (SHBG): P_rs3751591 = 0.03) and interacted with alcohol intake in relation to hormone levels (estrone sulphate: P_{interaction/rs2008691} = 0.02 and P_{interaction/rs1062033=} 0.03, and SHBG: P_{interaction/rs11070844} = 0.03). CYP19A1/rs3751591 was both associated with SHBG levels (P = 0.03) and with risk of BC (Incidence Rate Ratio = 2.12; 95 % Confidence Interval: 1.02–4.43) such that homozygous variant allele carriers had increased levels of serum SHBG and were at increased risk of BC. Acute intake of alcohol decreased blood estrone (P = <0.0001), estrone sulphate (P = <0.0001), and SHBG (P = 0.009) levels, whereas Ibuprofen intake and PPARG Pro¹²Ala genotype had no effect on hormone levels.

Conclusions

Our results suggest that genetically determined variation in CYP19A1 is associated with differences in sex hormone levels. However, the genetically determined differences in sex hormone levels were not convincingly associated with BC risk. The results therefore indicate that the genetically determined variation in CYP19A1 contributes little to BC risk and to alcohol-mediated BC risk.

Trial registration

NCT02463383, June 3, 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2317-y) contains supplementary material, which is available to authorized users.

Premature adrenarche--a common condition with variable presentation

Adrenarche refers to a maturational increase in the secretion of adrenal androgen precursors, mainly dehydroepiandrosterone (DHEA) and its sulfate (DHEAS). In premature adrenarche (PA), clinical signs of androgen action appear before the age of 8/9 years in girls/boys, concurrently with the circulating DHEA(S) concentrations above the usually low prepubertal level. The most pronounced sign of PA is the appearance of pubic/axillary hair, but also other signs of androgen effect (adult type body odor, acne/comedones, greasy hair, accelerated statural growth) are important to recognize. PA children are often overweight and taller than their peers, and the higher prevalence of PA in girls than in boys is probably explained by higher female adiposity and peripheral DHEA(S) conversion to active androgens. PA diagnosis requires exclusion of other causes of androgen excess: congenital adrenal hyperplasia, androgen-producing tumors, precocious puberty, and exogenous source of androgens. PA has been linked with unfavorable metabolic features including hyperinsulinism, dyslipidemia, and later-appearing ovarian hyperandrogenism. Although this common condition is usually benign, PA children with additional risk factors including obesity should be followed up, with the focus on weight and lifestyle. Long-term follow-up studies are warranted to clarify if the metabolic changes detected in PA children persist until adulthood.

Adolescence and polycystic ovary syndrome: current concepts on diagnosis and treatment

BACKGROUND

Adolescence is a time characterised by changes in reproductive hormones and menstrual patterns, which makes it difficult to diagnose polycystic ovary syndrome (PCOS) in this population. The diagnosis of PCOS has a great physical and psychosocial impact on the young person. Despite the importance of a diagnosis of PCOS at adolescence, data available are limited.

AIMS

This review focuses on analysing markers of PCOS diagnosis and possible treatments in adolescence.

RESULTS

Although, during adolescence, diagnosis criteria of PCOS overlap with physiological changes including clinical manifestations of hyperandrogenism (acne and hirsutism), oligo/amenorrhoea, anovulation and ovarian microcysts, there is agreement that irregular menses and hyperandrogenaemia should be used to diagnose PCOS in this population. Moreover, considering that PCOS phenotype could change through the reproductive age and that adolescents display heterogeneous ovarian morphology, it has been proposed that diagnosis of PCOS should be confirmed after the age of 18. The first-line treatment for menstrual irregularity and hirsutism are oral contraceptive pills (OCPs) and for obesity and metabolic abnormalities are lifestyle changes. Insulin-sensitizer drugs, such as metformin, may be added to the treatment in the presence of metabolic alterations. Antiandrogen drugs may also be associated for treating moderate to severe hirsutism. During adolescence, physiological changes overlap with signs and symptoms of PCOS; thus the diagnosis criteria should be carefully considered. Regarding the treatment of adolescents with PCOS, non-pharmacological interventions include lifestyle changes. Pharmacological treatments comprise OCPs, antiandrogens and metformin, used isolated or combined.

CONCLUSIONS

During adolescence, physiological changes overlap with signs and symptoms of PCOS; thus the diagnosis criteria should be carefully considered. Regarding the treatment of adolescents with PCOS, non-pharmacological interventions include lifestyle changes. Pharmacological treatments comprise OCPs, antiandrogens and metformin, used isolated or combined.

Genetics of androgen metabolism in women with infertility and hypoandrogenism

Hypoandrogenism in women with low functional ovarian reserve (LFOR, defined as an abnormally low number of small growing follicles) adversely affects fertility. The androgen precursor dehydroepiandrosterone (DHEA) is increasingly used to supplement treatment protocols in women with LFOR undergoing in vitro fertilization. Due to differences in androgen metabolism, however, responses to DHEA supplementation vary between patients. In addition to overall declines in steroidogenic capacity with advancing age, genetic factors, which result in altered expression or enzymatic function of key steroidogenic proteins or their upstream regulators, might further exacerbate variations in the conversion of DHEA to testosterone. In this Review, we discuss in vitro studies and animal models of polymorphisms and gene mutations that affect the conversion of DHEA to testosterone and attempt to elucidate how these variations affect female hormone profiles. We also discuss treatment options that modulate levels of testosterone by targeting the expression of steroidogenic genes. Common variants in genes encoding DHEA sulphotransferase, aromatase, steroid 5α-reductase, androgen receptor, sex-hormone binding globulin, fragile X mental retardation protein and breast cancer type 1 susceptibility protein have been implicated in androgen metabolism and, therefore, can affect levels of androgens in women. Short of screening for all potential genetic variants, hormonal assessments of patients with low testosterone levels after DHEA supplementation facilitate identification of underlying genetic defects. The genetic predisposition of patients can then be used to design individualized fertility treatments.

Premature adrenarche: etiology, clinical findings, and consequences

Adrenarche means the morphological and functional change of the adrenal cortex leading to increasing production of adrenal androgen precursors (AAPs) in mid childhood, typically at around 5-8 years of age in humans. The AAPs dehydroepiandrosterone (DHEA) and its sulfate conjugate (DHEAS) are the best serum markers of adrenal androgen (AA) secretion and adrenarche. Normal ACTH secretion and action are needed for adrenarche, but additional inherent and exogenous factors regulate AA secretion. Inter-individual variation in the timing of adrenarche and serum concentrations of DHEA(S) in adolescence and adulthood are remarkable. Premature adrenarche (PA) is defined as the appearance of clinical signs of androgen action (pubic/axillary hair, adult type body odor, oily skin or hair, comedones, acne, accelerated statural growth) before the age of 8 years in girls or 9 years in boys associated with AAP concentrations high for the prepubertal chronological age. To accept the diagnosis of PA, central puberty, adrenocortical and gonadal sex hormone secreting tumors, congenital adrenal hyperplasia, and exogenous source of androgens need to be excluded. The individually variable peripheral conversion of circulating AAPs to biologically more active androgens (testosterone, dihydrotestosterone) and the androgen receptor activity in the target tissues are as important as the circulating AAP concentrations as determinants of androgen action. PA has gained much attention during the last decades, as it has been associated with small birth size, the metabolic and polycystic ovarian syndrome (PCOS), and thus with an increased risk for type 2 diabetes and cardiovascular diseases in later life. The aim of this review is to describe the known hormonal changes and their possible regulators in on-time and premature adrenarche, and the clinical features and possible later health problems associating with PA.

Effects of resistin on ovarian folliculogenesis and steroidogenesis in the vespertilionid bat, Scotophilus heathi

The bat Scotophilus heathi exhibit prolonged anovulatory condition known as delayed ovulation coinciding with the period of extensive fat accumulation. The present study was undertaken to find out whether extensive accumulation of fat in S. heathi is responsible for suppression of ovarian activity by increasing production of adipokine resistin in the bat. This was achieved by (a) investigating variation in serum resistin level in relation to the changes in the body fat mass and (b) evaluating the effect of resistin treatment on ovarian activity with reference to steroid synthesis. An attempt was also made to determine whether resistin mediate its effects on ovary through signal transducer and activator of transcription 3 (STAT3) signaling mechanism. The results showed significant seasonal variation in serum resistin level with the peak level coinciding with the period of maximum fat accumulation, high circulating androgen level and period of anovulation. The treatment with resistin to the bat caused increase in androstenedione due to stimulatory effects on 3β-hydroxysteroid dehydrogenase, but decrease in estradiol level due to inhibitory effect on aromatase. Resistin treatment increased androgen receptor protein together with increased insulin receptor but not through conventional luteinizing hormone receptor and steroidogenic acute regulatory protein mediated pathways. This study further showed that resistin treatment increases androstenedione synthesis and up-regulates insulin receptor in the ovary through STAT3 mediated pathways. These findings suggest that obese women through increased resistin synthesis may causes development of non-ovulatory antral follicles through insulin receptor signaling cascade.

Uncovering steroidopathy in women with autism: a latent class analysis

Background

Prenatal exposure to increased androgens has been implicated in both polycystic ovary syndrome (PCOS) and autism spectrum conditions (ASC), suggesting that PCOS may be increased among women with ASC. One study suggested elevated steroidopathic symptoms (‘steroidopathy’) in women with ASC. As the symptoms are not independent, we conducted a latent class analysis (LCA). The objectives of the current study are: (1) to test if these findings replicate in a larger sample; and (2) to use LCA to uncover affected clusters of women with ASC.

Methods

We tested two groups of women, screened using the Autism Spectrum Quotient - Group 1: n = 415 women with ASC (mean age 36.39 ± 11.98 years); and Group 2: n = 415 controls (mean age 39.96 ± 11.92 years). All participants completed the Testosterone-related Medical Questionnaire online. A multiple-group LCA was used to identify differences in latent class structure between women with ASC and controls.

Results

There were significant differences in frequency of steroid-related conditions and symptoms between women with ASC and controls. A two-class semi-constrained model best fit the data. Based on response patterns, we identified the classes as ‘Typical’ and ‘Steroidopathic’. The prevalence of the ‘Steroidopathic’ class was significantly increased within the ASC group (ΔG² = 15, df =1, P = 0.0001). In particular, we confirmed higher frequencies of epilepsy, amenorrhea, dysmenorrhea, severe acne, gender dysphoria, and transsexualism, and differences in sexual preference in women with ASC.

Conclusions

Women with ASC are at increased risk for symptoms and conditions linked to steroids. LCA revealed this steroidopathy despite the apparent underdiagnosis of PCOS.

Adipocyte biology in polycystic ovary syndrome

Polycystic Ovary Syndrome (PCOS) is a common endocrinopathy that is associated with an adverse metabolic profile including insulin resistance. There is a clear association between obesity, the development of PCOS and the severity of its phenotypic, biochemical and metabolic features. Evidence to support this link includes data from epidemiological, pathophysiological and genetic studies. Given the importance of obesity in the development and manifestation of PCOS, ongoing research into the many facets of adipocyte biology in women with the condition is important and should continue to be a priority. In this review article, we discuss the existing literature on fat distribution, adipokines, adipocyte hypertrophy and adipocyte steroid metabolism in women with PCOS.

The expression of sex steroid synthesis and inactivation enzymes in subcutaneous adipose tissue of PCOS patients

Modulation of sex steroid pre-receptor in adipose tissue is important for the development of metabolic diseases, but its roles in the pathogenesis of polycystic ovary syndrome (PCOS) has not been fully characterized. Herein we compared the expression of key sex steroid converting enzymes in the subcutaneous adipose tissue (SAT) between patients with PCOS and the matched controls. Most of the sex steroid converting enzymes were highly expressed in the SAT, except 17α-hydroxylase (CYP17A1). Compared with the controls, PCOS patients showed significantly higher levels of 3β-hydroxysteroid dehydrogenase1-2 (3β-HSD1-2), aldo-keto reductase 1C 1-3 (AKR1C1-3) and leptin, but lower level of P450 aromatase and 5α-reductase 1. Interestingly, leptin was positively correlated to AKR1C2 expression and negatively to 5α-reductase1 as well as peroxisome proliferator-activated receptor γ (PPARγ). In summary, the expression of enzymes synthesizing testosterone and enzymes inactivating DHT and progesterone was higher in SAT of PCOS patients compared to controls. Correlation analysis indicated that increased leptin expression may be negatively related to local DHT level. These data suggested that sex steroid converting enzymes expression was different in SAT of PCOS patients that might contribute to abnormal testosterone and leptin level of PCOS patients.

Aromatase gene polymorphism does not influence clinical phenotype and response to oral contraceptive pills in polycystic ovary syndrome women

AIMS

To assess whether a single nucleotide polymorphism (SNP50) of the aromatase gene (CYP19) is associated with polycystic ovary syndrome (PCOS) phenotypes and to investigate the influence of this polymorphism on the response of PCOS to treatment with oral contraceptive pills (OCP).

METHODS

162 hirsute women were stratified into a classic PCOS group (hyperandrogenism, ovulatory dysfunction, c-PCOS) and an ovulatory PCOS group (hyperandrogenism, ovulatory cycles, polycystic ovaries, ov-PCOS). 51 women completed a 6-month OCP trial (20 µg ethinyl estradiol + 75 µg gestodene, 21/28 days per cycle, plus 100 mg spironolactone in 32 women with moderate to severe hirsutism). We considered the presence of the polymorphic allele A (AG+AA) in comparison to the absence of the polymorphism (GG) to express results and to perform the comparisons regarding clinical variables.

RESULTS

Mean age was 23.3 ± 6.9 years. Hirsutism score was similar in c-PCOS and ov-PCOS (15 (11-20) vs. 13 (11-20)). The differences in hormone and metabolic variables between phenotypes were independent of the presence of allele A. In the OCP trial subsample, no differences were observed between genotypes after 6 months' treatment.

CONCLUSION

The differences between c-PCOS and ov-PCOS cannot be explained by the genetic variation at SNP50 in the CYP19 gene.

Four polymorphisms of the CAPN 10 gene and their relationship to polycystic ovary syndrome susceptibility: a meta-analysis

OBJECTIVE

  To investigate the association between CAPN 10 gene polymorphism and polycystic ovary syndrome (PCOS) susceptibility.

DESIGN

Meta-analysis of published case-control studies of four single nucleotide polymorphisms (SNPs) in CAPN 10 and PCOS susceptibility.

PATIENTS

  Women with PCOS.

MEASUREMENTS

  Odds ratios (ORs) and 95% confidence intervals (CIs) for heterozygous, homozygous, dominant model, recessive model and allele.

RESULTS

  A total of 11 studies were involved in the meta-analysis. UCSNP-63 was significantly associated with PCOS, with homozygous carriers (TT vs CC: OR = 0·64; 95% CI: 0·45-0·90) and recessive model (TT vs CC and CT: OR = 0·64; 95% CI: 0·45-0·90) being protective factors. In addition, UCSNP-19 was significantly associated with PCOS, with recessive model (ins/ins vs del/del and del/ins: OR = 0·72, 95% CI: 0·59-0·88) and insert allele (ins vs del: OR = 0·85, 95% CI: 0·76-0·96) being protective factors, while heterozygous carriers (del/ins vs del/del: OR = 1·56, 95% CI: 1·24-1·94) and deletion allele (del vs ins: OR = 1·18, 95% CI: 1·04-1·32) being risk factors. However, no significant associations were found between UCSNP-44, -43 and PCOS. Moreover, the results of the Rotterdam criteria subgroup analysis were similar with that of overall analysis.

CONCLUSIONS

  This is the first report on the association between CAPN 10 UCSNP-63 and PCOS in genotype, with homozygous carriers and recessive model being protective factors. Additionally, insert allele and recessive model of UCSNP-19 are protective factors, while deletion allele and heterozygous genotype are risk factors for PCOS development.

Genetic polymorphisms associated with steroids metabolism and insulin action in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is an endocrinopathy associated with infertility, diabetes and cardiovascular events. This study aimed to correlate polymorphisms of genes involved in the biosynthesis and metabolism of steroids and insulin action (CYP17A1, CYP19A1, AR, ESR1, ESR2, INSR, IGF2 and PAI1) with clinical and biochemical parameters of PCOS. DNA was extracted from peripheral blood samples obtained from 117 PCOS and 105 healthy women. The PAI1 insertion/deletion (-675 ins/delG) polymorphism (rs1799768) was genotyped by PCR-SSCP. CYP19A1 [TTTA](n), AR [CAG](n), ESR1 [TA](n), and ESR2 [CA](n) genes were evaluated by PCR-based GeneScan analysis, while CYP17A1 5'UTR (rs743572), INSR 1058 CT (rs1799817), and IGF2 3'UTR GA (rs680) polymorphisms were evaluated by PCR-RFLP. The results showed a prevalence of PAI1 4G5G+4G4G genotypes in PCOS (p = 0.025). Younger PCOS women showed a predominance of CT+TT, GA+AA and 4G5G+4G4G genotypes of INSR, IGF2, and PAI1 (p = 0.0499, p = 0.0300, p = 0.0350, respectively). AR shorter alleles (≤ 20 repeats) were significantly associated with higher serum levels of total testosterone (TT, p = 0.0086). In conclusion, PAI1 polymorphism seems to be associated with the risk of PCOS development. Younger PCOS women had specific genotypes of INSR, IGF2 and PAI1 genes. AR shorter alleles can be associated with higher serum levels of TT in PCOS patients.

Understanding polycystic ovarian syndrome pathogenesis: an updated of its genetic aspects

Polycystic ovary syndrome (PCOS) is the most frequent cause of female infertility. It is also characterized by metabolic defects that raise the risk for cardiovascular disease. Despite the progress in the definition of the clinical aspects of the syndrome, only very few definite data are available about the ethiopathogenetic mechanisms that subtend PCOS. It is likely that the PCOS phenotype derives from the interaction between environmental and genetic factors. While environmental factors have easily been investigated, the individuation of the genetic factors seem to be more complex. Indeed, PCOS appears to be inherited as a complex, polygenic trait. Several family studies have been conducted with the aim to clarify the genetic aspects of PCOS, but their findings are often conflicting and not conclusive.Moreover, it is difficult to establish with certainty which genes are involved and their effective role in the development of the syndrome because in PCOS, genetic analysis is hampered by low fecundity, lack of a male phenotype, absence of an animal model, and dissimilarity of the diagnostic criteria used to select the patients. Since multiple biochemical pathways are implicated in PCOS pathogenesis, genes of steroid hormone metabolism, gonadotropin release and action, insulin secretion and action, adipose tissue metabolism and others have been investigated. Nevertheless, none of them seems to play a key role in the ethiopathogenesis of PCOS. This article reviews the large body of literature generated to support the presence of genetic abnormalities in PCOS women by taking in consideration the most important studies regarding PCOS candidate genes.

The Genetic Basis of the Polycystic Ovary Syndrome: A Literature Review Including Discussion of PPAR-gamma

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder of the women of reproductive age. Familial clustering of PCOS has been consistently reported suggesting that genetic factors play a role in the development of the syndrome although PCOS cases do not exhibit a clear pattern of Mendelian inheritance. It is now well established that PCOS represents a complex trait similar to type-2 diabetes and obesity, and that both inherited and environmental factors contribute to the PCOS pathogenesis. A large number of functional candidate genes have been tested for association or linkage with PCOS phenotypes with more negative than positive findings. Lack of universally accepted diagnostic criteria, difficulties in the assignment of male phenotype, obscurity in the mode of inheritance, and particularly small sample size of the study populations appear to be major limitations for the genetic studies of PCOS. In the near future, utilizing the genome-wide scan approach and the HapMap project will provide a stronger potential for the genetic analysis of the syndrome.

Report of the international symposium: polycystic ovary syndrome: first Latin-American consensus

During the last years, numerous consensuses have been held in different countries in order to review the data concerning diagnosis and treatment and their relationship with the ethnic origin, social status and lifestyle of women with Polycystic Ovary Syndrome (PCOS). This study describes the conclusions concerning diagnostic criteria and the appropriate treatment of women with PCOS reached during the International Symposium Polycystic Ovary Syndrome, First Latin-American Consensus held in Buenos Aires, Argentina on 4th and 5th May 2009 to be applied in South American.

Pubertal development in ALG6 deficiency (congenital disorder of glycosylation type Ic)

Information on the hypothalamic pituitary ovarian axis in congenital disorders of glycosylation (CDG) females is scarce. Varying hormonal profiles and degrees of virilization in CDG females suggest a spectrum of yet unidentified mechanisms affected by impaired N-glycosylation. We describe an ALG6D woman who completed puberty with normal gonadotropins and testosterone levels, no virilization, and regular menses. Hormonal follow-up of CDG females is necessary to improve our understanding of the role of glycosylation in pubertal development.

Genetic basis of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is associated with obesity and manifests with reproductive, hyperandrogenic and metabolic features. Although the etiology of PCOS is complex and incompletely understood, genetics plays an important role (heritability: ∼70%). Potential problems with studying the genetics of PCOS include the heterogeneity of the condition and associated sub-fertility. A candidate gene approach has been used in over 70 published studies on PCOS, most of which have been inadequately powered to detect a statistically meaningful association. Furthermore, these studies often fail to replicate prior published studies on the same candidate gene in different populations. The first genome-sequence variant (identified from a genome-wide association study in subjects with Type 2 diabetes mellitus) to be studied in PCOS (FTO gene) has been shown by our group to associate with susceptibility for the development of PCOS. This is the first genetic corroboration of a link between PCOS and obesity. Future directions include a genome-wide association study in PCOS.

Association between CYP19 gene SNP rs2414096 polymorphism and polycystic ovary syndrome in Chinese women

Background

Several studies have reported the association of the SNP rs2414096 in the CYP19 gene with hyperandrogenism, which is one of the clinical manifestations of polycystic ovary syndrome (PCOS). These studies suggest that SNP rs2414096 may be involved in the etiopathogenisis of PCOS. To investigate whetherthe CYP19 gene SNP rs2414096 polymorphism is associated with the susceptibility to PCOS, we designed a case-controlled association study including 684 individuals.

Methods

A case-controlled association study including 684 individuals (386 PCOS patients and 298 controls) was performed to assess the association of SNP rs2414096 with PCOS. Genotyping of SNP rs2414096 was conducted by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method that was performed on genomic DNA isolated from blood leucocytes. Results were analyzed in respect to clinical test results.

Results

The genotypic distributions of rs2414096 (GG, AG, AA) in the CYP19 gene (GG, AG, AA) in women with PCOS (0.363, 0.474, 0.163, respectively) were significantly different from that in controls (0.242, 0.500, 0.258, respectively) (P = 0.001). E2/T was different between the AA and GG genotypes. Age at menarche (AAM) and FSH were also significantly different among the GG, AG, and AA genotypes in women with PCOS (P = 0.0391 and 0.0118, respectively). No differences were observed in body mass index (BMI) and other serum hormone concentrations among the three genotypes, either in the PCOS patients or controls.

Conclusions

Our data suggest that SNP rs2414096 in the CYP19 gene is associated with susceptibility to PCOS.

Adipose tissue expandability and the early origins of PCOS

The most prevalent phenotypes of polycystic ovary syndrome (PCOS) are characterized by insulin resistance and androgen excess. The adipose tissue (AT) expandability hypothesis explains the development of insulin resistance in obesity and in cases of AT deficit. In line with this hypothesis, we propose that hyperinsulinemic androgen excess in PCOS is often underpinned by exhaustion of the capacity to expand subcutaneous AT in a metabolically safe way. Such exhaustion might occur when a positive energy imbalance meets a normal fat-storage capacity and/or when a normal energy balance faces a low fat storage capacity. This concept thus explains how PCOS phenotypes might result from obesity, prenatal growth restraint or a genetic lipodystrophy, or, experimentally, from prenatal androgen excess.

Genetic variation of FTO and TCF7L2 in premature adrenarche

Premature adrenarche (PA) has been associated with increased body mass index. Our aim was to determine whether the obesity-associated variant at fat mass and obesity gene (FTO) is more frequent in PA subjects. Furthermore, we hypothesized that altered Wnt signaling due to genetic variants at transcription factor 7-like 2 (TCF7L2) could play a role in the polygenic pathogenesis of PA. We genotyped polymorphisms at FTO rs9939609 and at TCF7L2 rs7903146 and rs12255372 in 73 Finnish white prepubertal children with PA and in 97 age- and sex-matched healthy controls. In addition, we investigated the associations of these genetic variations with weight, height, circulating adrenocortical hormone levels, glucose metabolism, lipid profile, and blood pressure. The differences in the minor allele frequencies (MAFs) of rs9939609, rs7903146, and rs12255372 were not statistically significant between the PA and control groups (difference in MAFs [95% confidence interval]: -0.06 [-0.18, 0.05], 0.04 [-0.05, 0.12], and 0.01 [-0.07, 0.10]; P = .3, .4, and .8, respectively). However, the risk allele at TCF7L2 rs7903146 was more frequent in PA subjects than in controls when we restricted the analysis to the subjects with lower weight-for-height than the median of the PA subjects (weight-for-height <108%, corresponding body mass index SD score <0.79; difference in MAFs [95% confidence interval]: 0.12 [-0.001, 0.23]; P = .038). Risk variant at FTO rs9939609 associated with higher weight-for-height in the healthy children (P = .001). In conclusion, the minor variant at FTO rs9939609 seems to play no major role in the increased weight-for-height of PA subjects; but the risk allele at TCF7L2 rs7903146 may have a role in the pathogenesis of PA in lean subjects.

Expressed sequence tags (ESTs) and single nucleotide polymorphisms (SNPs): What large-scale sequencing projects can tell us about ADME

To date over 800 complete genomes have been sequenced, with many more partially complete. Coupled with the large amount of mRNA transcript sequence data being produced from expression studies, there is now a daunting amount of information available to the research scientist. This review examines how this information may be best used, focusing on examples from sequences encoding absorption, distribution, metabolism and excretion (ADME)-related proteins in particular. Through the use of phylogenetic, splice variant and single nucleotide polymorphism (SNP) analysis, the review examines not only how insights into species-specific responses to drug exposure may be gained, but also how best to utilize this information to predict both individual human responses and the impact of population variance in response.

LRP5 in premature adrenarche and in metabolic characteristics of prepubertal children

OBJECTIVE

Premature adrenarche (PA) is associated with unfavourable metabolic characteristics. We hypothesized that genetic variation in low density lipoprotein (LDL) receptor-related protein 5 (LRP5), which is involved in Wnt signalling in the adrenal cortex and in cholesterol metabolism, plays a role in the pathogenesis of PA.

DESIGN AND PATIENTS

We performed a cross-sectional association study in 73 Finnish children with PA and 97 age- and gender-matched healthy controls.

MEASUREMENTS

LRP5 genotypes were determined by direct sequencing. Single-marker associations with clinical-metabolic characteristics, including adrenocortical function, glucose tolerance and lipid profile, were examined with age and gender as covariates.

RESULTS

Nineteen single nucleotide polymorphisms (SNPs) in LRP5 were found in the 170 children. No significant differences in the genotype distributions were observed between the PA and control groups. SNPs A1330V and N740N were associated with higher serum dehydroepiandrosterone sulphate (DHEAS) levels in the control subjects (A/A vs. A/a; mean 0.8 vs. 1.4 micromol/l, P = 0.01). They were also associated with higher plasma levels of total (4.2 vs. 4.7 mmol/l, P = 0.02) and LDL cholesterol (2.4 vs. 2.9 mmol/l, P = 0.02) in the control group, as was SNP V1119V (P = 0.04 and P = 0.03, respectively). SNPs F549F and V1119V were associated with higher systolic blood pressure (P = 0.04 and P = 0.02, respectively). There were no differences in the parameters of glucose metabolism between the genotype groups.

CONCLUSIONS

Genetic variation in LRP5 did not predispose to PA but was associated with metabolic characteristics, especially lipid profile, in healthy prepubertal children.

CYP19 gene: a genetic modifier of polycystic ovary syndrome phenotype

OBJECTIVE

To evaluate the possible contribution of the (TTTA)n polymorphism of aromatase gene (CYP19) to the hyperandrogenic phenotype of polycystic ovary syndrome (PCOS).

DESIGN

Case-control study.

SETTING

Endocrine outpatients' clinic of a tertiary university hospital.

PATIENT(S)

One hundred eighty women with PCOS and 160 healthy controls of reproductive age.

INTERVENTION(S)

Blood sampling for genotype analysis, and measurement of androgens, E(2), LH, FSH, and fasting glucose and insulin.

MAIN OUTCOME MEASURE(S)

Frequency of the CYP19(TTTA)n polymorphism and association with hormone concentrations.

RESULT(S)

Women with PCOS tended to have more frequently short (TTTA)n alleles (with nine or fewer repeats) than healthy controls (33.1% vs. 29.5%), although the difference was not statistically significant. However, patients in the highest quartile for serum T were more frequently homozygous for short alleles compared with controls (59.1% vs. 42.1%) and patients in lower quartiles (59.1% vs. 36.9%). Furthermore, the patients homozygous for short alleles had higher T/E(2) ratios, higher T levels, and higher LH/FSH ratios compared with those with longer alleles.

CONCLUSION(S)

Although CYP19 may not be a major genetic determinant of PCOS, it may act as a genetic modifier of the hyperandrogenic phenotype of PCOS. The presence of short CYP19(TTTA)n alleles may contribute to prenatal androgenization programming the development of PCOS phenotype in adult life.

Association between CYP19A1 polymorphisms and sex hormones in postmenopausal Japanese women

In postmenopausal women, extraovarian sex hormone production plays an important role in hormone-related diseases, such as breast and endometrial cancers. Aromatase, an enzyme encoded by CYP19A1, is a key enzyme involved in estrogen biosynthesis. The impact of CYP19A1 polymorphisms on serum sex hormone levels in the Japanese population has never been investigated. This study enrolled 100 postmenopausal Japanese women found to be without cancer. Twenty-five CYP19A1 loci were identified, and measurements were conducted on serum levels of sex hormones; lifestyle data were collected, namely estrone (E1), estradiol (E2), testosterone and sex hormone-binding globulin (SHBG). We conducted a cross-sectional analysis to evaluate the impact of CYP19A1 haplotype on serum sex hormone levels. We found that subjects with BMI>or=25 kg/m(2) showed a significant difference in circulating testosterone levels (0.29+/-0.19, P=0.050). Neither age nor the amount of physical exercise or drinking habits showed any effect on hormone levels. We identified seven haplotype blocks in CYP19A1 by LD analysis. Estrone levels differed in rs12148604 (SNP 1) and rs11632903 (SNP14). No significant locus for estradiol was observed. SHBG levels were associated with rs4441215 (SNP11). Testosterone levels were strongly associated with rs752760 (SNP24) and rs2445768 (SNP25) and weakly associated with SNP 1, SNP11 and SNP14 as well. We found that polymorphisms in CYP19A1 influence sex hormone levels in Japanese postmenopausal women.

Female reproductive disorders: the roles of endocrine-disrupting compounds and developmental timing

OBJECTIVE

To evaluate the possible role of endocrine-disrupting compounds (EDCs) on female reproductive disorders emphasizing developmental plasticity and the complexity of endocrine-dependent ontogeny of reproductive organs. Declining conception rates and the high incidence of female reproductive disruptions warrant evaluation of the impact of EDCs on female reproductive health.

DESIGN

Publications related to the contribution of EDCs to disorders of the ovary (aneuploidy, polycystic ovary syndrome, and altered cyclicity), uterus (endometriosis, uterine fibroids, fetal growth restriction, and pregnancy loss), breast (breast cancer, reduced duration of lactation), and pubertal timing were identified, reviewed, and summarized at a workshop.

CONCLUSION(S)

The data reviewed illustrate that EDCs contribute to numerous human female reproductive disorders and emphasize the sensitivity of early life-stage exposures. Many research gaps are identified that limit full understanding of the contribution of EDCs to female reproductive problems. Moreover, there is an urgent need to reduce the incidence of these reproductive disorders, which can be addressed by correlative studies on early life exposure and adult reproductive dysfunction together with tools to assess the specific exposures and methods to block their effects. This review of the EDC literature as it relates to female health provides an important platform on which women's health can be improved.

Sex-specific differences in CYP450 isoforms in humans

BACKGROUND

The activity of various CYP isoforms is critical for maintaining the clinical effectiveness of many medications. Therefore, determining the sex-dependent activity of clinically relevant CYP families is highly important for optimal therapeutic effectiveness.

OBJECTIVE

This review examined the sex-dependent activity of CYP3A, CYP1A2, CYP2D6, CYP2C9, CYP2C19 and CYP2E1.

METHODS

This review searched for studies performed in humans and hormonal status was not a limiting factor.

RESULTS/CONCLUSIONS

The current evidence suggests that CYP2E1 and CYP1A2 activity is higher in males than females, while CYP3A, one of the most clinically relevant CYP isoforms, appears to have greater activity in females. Overall, more studies are needed to fully support these conclusions as there are many factors that influence drug metabolism and thus it is very difficult to isolate gender as a sole modulator of CYP activity.

Functional genetic polymorphisms and female reproductive disorders: Part I: Polycystic ovary syndrome and ovarian response

BACKGROUND

The identification of polymorphisms associated with a disease can help to elucidate its pathogenesis, and this knowledge can be used to improve prognosis for women with a particular disorder, such as polycystic ovary syndrome (PCOS). Since an altered response to ovarian stimulation is also a characteristic of the disease, further knowledge about its aetiology could help in defining the parameters that determine the response of an individual to ovarian stimulation.

METHODS

PubMed and EMBASE databases were systematically searched for gene association studies published until the end of August 2007, using search criteria relevant to PCOS and ovarian response to stimulation. Data from additional papers identified through hand searches were also included; 139 publications were reviewed.

RESULTS

Several genes involved in ovarian function and metabolism are associated with increased susceptibility to PCOS, but none is strong enough to correlate alone with susceptibility to the disease, or response to therapy. A single-nucleotide polymorphism in exon 10 of the FSH receptor (FSHR) gene, FSHR p.N680S, was consistently identified as having a significant association with ovarian response to FSH.

CONCLUSIONS

No consistent association between gene polymorphism and PCOS could be identified. The FSHR gene may play a significant role in the success of ovarian stimulation, and can be used as a marker to predict differences in FSHR function and ovarian response to FSH. Genotyping the FSHR p.N680S polymorphism may provide a means of identifying a population of poor responders before in vitro fertilization procedures are initiated.