Unexpectedly high mutation rate of cyp11b1 compared to cyp21a2 in randomly-selected turkish women: a large screening study

PURPOSE

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders resulting from enzyme deficiencies associated with steroidogenesis. The clinical presentation of non-classic CAH (NCAH) in females is often indistinguishable from other hyperandrogenic disorders like polycystic ovary syndrome (PCOS). The data on the prevalence of NCAH in unselected women in the literature is scanty. The research aimed to evaluate the prevalence of NCAH, carrier frequencies, and the correlation between clinical symptoms and genotype in Turkish women.

METHODS

The study group comprised two hundred and seventy randomly-selected unrelated asymptomatic women of reproductive age (18-45). Subjects were recruited from female blood donors. All volunteers underwent clinical examination and hormone measurements. The protein-encoding exons and exon-intron boundaries of the CYP21A2, CYP11B1, HSD3β2 and CYP21A2 promoter were sequenced by direct DNA sequencing.

RESULTS

After genotyping, seven (2.2%) individuals were diagnosed with NCAH. The heterozygous carrier frequencies of CYP21A2, CYP21A2 promoter, CYP11B1, and HSD3β2 genes with 34, 34, 41, and 1 pathologic mutation were determined at 12.6%, 12.6%, 15.2%, and 0.37% of volunteers, respectively. Gene-conversion (GC) frequencies between CYP21A2/CYP21A1P and CYP11B1/CYP11B2 were determined as 10.4% and 14.8%, respectively.

CONCLUSION

Despite GC-derived higher mutation frequency determined in the CYP11B1 gene, the reason for the low frequency of NCAH due to 11OHD compared to 21OHD might be that gene-conversion arises with active CYP11B2 rather than an inactive pseudogene. HSD3β1 exhibits high homology with HSD3β2 located on the same chromosome; remarkably, it demonstrates low heterozygosity and no GC, most probably the outcome of a tissue-specific expression pattern.

The role of androgen receptor CAG repeat polymorphism in androgen excess disorder and idiopathic hirsutism

PURPOSE

The study aimed to investigate whether repeat number in the androgen receptor (AR) gene has any contribution to phenotypes of the disease of androgen excess (polycystic ovary syndrome (PCOS), idiopathic hyperandrogenemia (IHA) and idiopathic hirsutism (IH) in a cohort of Turkish women.

METHODS

Three hundred and fifty-four voluntary premenopausal women (172 healthy controls and 182 patients with androgen excess disorders and idiopathic hirsutism) 18-45 years of age seen at an outpatient endocrine clinic at Erciyes University Hospital between January 2013 and December 2014 were included. All volunteers have undergone physical examination and biochemical evaluation. The polymorphic (CAG)n repeat of the human AR was determined by fragment analyses.

RESULTS

Detailed clinical analyses of the patients ended up with 137 PCOS, 24 IHA, and 21 IH. Pairwise comparisons revealed the CAG repeat number differences between the PCOS and controls (p = 0.005) and IH and controls (p = 0.020). Women with CAG repeat length ≤ 17 had a significantly increased twofold risk for PCOS than those women with > 17 CAG repeats OR: 2.0 (95% CI 1.2-3.3, p = 0.005). Women with CAG repeat length ≤ 17 had a significantly increased threefold risk for IH than those women with > 17 CAG repeats OR: 2.9 (95% CI 1.2-7.3, p = 0.020). When correlation analysis was performed, a weak negative correlation was detected between the short allele and FGS score (r = - 0.131, p = 0.013) and a positive relationship between total testosterone and longer allele in the IHA group (r = 0.425, p = 0.039). Median repeat length of the shorter allele between oligomenorrhea and woman with normal menstrual cycle was found to be statistically significant (p = 0.017).

CONCLUSION

This study indicated that the risk of PCOS and IH is associated with the inheritance of ARs with shorter CAG repeats.

Comprehensive genotyping of Turkish women with hirsutism

INTRODUCTION

Hirsutism is a medical sign rather than a disease affects 5-8% of women of reproductive age. Hirsutism is associated with hyperandrogenemia in most patients excluding those with idiopathic hirsutism (IH). The most common cause of hirsutism is polycystic ovary syndrome (PCOS) followed by IH and idiopathic hyperandrogenemia (IHA); however, the clinical presentation of non-classical congenital adrenal hyperplasia (NCAH) in females is often indistinguishable from other hyperandrogenic disorders with common clinical signs such as hirsutism.

OBJECTIVE

The primary aim of the study is to examine the physical properties of the three genes and to make a detailed comparison of the mutations with the clinical data to contribute the etiology of hirsutism.

SUBJECTS AND METHODS

122 women admitted to the Endocrinology Clinic at Erciyes University Hospital with hirsutism were enrolled in the study between 2013-2014. All the participants were clinically evaluated. Protein-encoding exons, exon-intron boundaries of CYP21A2 (including proximal promoter), CYP11B1 and HSD3B2 genes were analyzed via state-of-the-art genetic studies.

RESULTS

DNA sequencing analyses revealed two homozygous and three compound heterozygous 21-hydroxylase deficient (21OHD) NCAH patients. Additionally, three novel CYP21A2 mutations (A89V, M187I and G491S) and two novel CYP11B1 mutations (V188I and G87A) were determined. The frequencies of heterozygous mutations in CYP21A2 (including promoter), CYP11B1 and HSD3B2 genes were determined as 26.5% (15% coding region, 11.5% promoter), 11.5% and 0%, respectively.

CONCLUSION

21OHD-NCAH prevalence was determined to be ~4%. Unexpectedly, high heterozygous mutation rates were observed in CYP11B1 gene and CYP21A2 promoter region. CYP11B1 and HSD3B2 deficiencies were not prevalent in Turkish women with hirsutism despite the existence of higher heterozygous mutation rate in CYP11B1.

Comparison of spironolactone and spironolactone plus metformin in the treatment of polycystic ovary syndrome

The aim of this study was to evaluate and compare the effects of spironolactone and spironolactone plus metformin treatments on body mass index (BMI), hirsutism score, hormone levels, and insulin resistance in women with polycystic ovary syndrome (PCOS). Thirty-seven patients with PCOS were randomly assigned to receive spironolactone 100 mg/d (spironolactone group, 18 patients) or spironolactone 100 mg/d plus metformin 2000 mg/d (combination group, 19 patients) for 12 months. BMI, modified Ferriman-Gallway score (FGS), serum levels of regarding hormones, and homeostasis model assessment of insulin resistance (HOMA-IR) index were assessed before and after the treatments. Six patients in the spironolactone group and four patients in the combination group reported inter-menstrual vaginal bleeding during treatments. In hirsutism scores, the spironolactone therapy resulted in 25.2% reduction, while combination therapy resulted in 28.3% reduction (p > 0.05, between groups). When the groups were compared in terms of percent changes in BMI, FGS, HOMA-IR, and hormone values other than free testosterone, no significant difference was noted. In the present study, FGSs were significantly decreased in both groups; however, combination therapy was not more effective than spironolactone alone in terms of BMI, FGS, hormone levels, or insulin resistance.

Is idiopathic hirsutism (IH) really idiopathic? mRNA expressions of skin steroidogenic enzymes in women with IH

OBJECTIVE

Hirsutism results from hyperandrogenemia and/or exaggerated androgen responsiveness. Among various causes of hirsutism, some patients do not exhibit androgen excess which is called idiopathic hirsutism (IH). The pathogenesis of IH could not so far be clearly established.

DESIGN

To investigate the mRNA expression of aromatase enzyme and the other enzymes having functional roles in the steroidogenic pathway, in freshly obtained skin tissue from subumbilical skin and the arm of the patients with IH and healthy women.

METHODS

Twenty-one women with IH and 15 healthy women were included in the study. We aimed to determine mRNA expressions of genes associated with local androgen synthesis and metabolism (CYP11A1, STS, CYP19A1, SRD5A1, SRD5A2, HSD3B1, AR, COMT, ESR1, ESR2, HSD3B2, CYP17A1, SULT2A1, SULT1E1, HSD17B2, IL6, TGFB1, TNFA) from skin biopsy and blood samples of patients with IH and the data compared with healthy subjects.

RESULTS

Patients with IH exhibit significantly lower interleukin 6 (IL6) mRNA expression and higher steroid sulphatase (STS) and hydroxysteroid (17beta) dehydrogenase 2 (HSD17B2), gene mRNA expression, respectively, in the subumbilical region skin biopsies. Similarly, patients with IH exhibit significantly lower IL6 mRNA expression and higher STS and HSD17B2 gene mRNA expression, respectively, in the arm skin compared to healthy women's subumbilical region.

CONCLUSIONS

In both arm and subumbilical skin biopsy of patients with IH, we observed an up-regulation of HSD17B2 and STS, decreased IL6 mRNA expression, probably determining an increase in the local amount of active androgens, which could then be used as substrate for other androgen metabolic routes.