Clinical and genetic analyses of a Chinese female with 17α-hydroxylase/17,20-lyase deficiency

Aims: 17α-Hydroxylase/17,20-lyase deficiency (17OHD) is a rare autosomal recessive disease caused by CYP17 gene mutations. This disease is clinically characterised by hypertension, hypokalaemia, sexual infantilism in females or pseudohermaphroditism in males, and adrenal hyperplasia. This study aims to investigate a rare case of 17OHD accompanied by both cystic ovaries and massive adrenal mass.

Methods: This study performed clinical, hormonal, radiological and genetic analyses. Blood samples were collected from the patient for the genetic test. Genomic DNA was extracted from peripheral blood leukocytes, and the coding sequence abnormalities of CYP17 were assessed using polymerase chain reaction and direct sequencing analysis.

Results: The genetic analysis of CYP17 revealed compound heterozygous mutations in the individual. One was a mis-sense mutation of c.1226 C?>?G, which changes codon 409 in exon 7 from proline (CCG) to arginine (CGG). Another was a mutation of p.Val311Asp,fs,330X, which was first reported in a compound heterozygote mutation of Y329fs and V311fs from a Chinese patient.

Conclusion: This study presented a rare case of 17OHD accompanied by both cystic ovaries and massive adrenal mass. This study obtained significant information on the genotype–phenotype correlation of 17OHD.     

Phenotypic variation in a Chinese family with 46,XY and 46,XX 17α-hydroxylase deficiency

Background: 17α-hydroxylase deficiency is a rare autosomal recessive disorder characterized by sexual infantilism, amenorrhea, hypertension and hypokalemia, which is caused by mutations in the CYP17A1 gene. To date, more than 50 mutations in this gene have been described. Methods: The clinical features and biochemical data of a pair of 46,XY and 46,XX Chinese siblings with 17α-hydroxylase deficiency from Singapore were studied. Direct DNA sequence analysis of the CYP17A1 gene was performed. Results: There was significant phenotypic variation between the siblings. The proband (46,XY) presented classically with sexual infantilism, amenorrhea and hypertension. The younger sibling (46,XX) also presented with amenorrhea, but she had breast development and absence of hypokalemic hypertension. The same compound heterozygous mutations in CYP17A1 gene were identified in both patients. A missense mutation (P409R) was detected in exon 7, and a 9-bp deletion (D487-S488-F489del) was detected in exon 8. Conclusion: We confirmed the diagnosis of 17α-hydroxylase deficiency in these two patients. Both P409R and D487-S488-F489del have been described previously and are widely propagated in the Chinese population in East and Southeast Asia. We propose that the phenotypic expression of affected individuals with 17α-hydroxylase deficiency is karyotype-dependent, with individuals having the 46,XX karyotype having less pronounced clinical symptoms.     

Homozygous CYP17A1 mutation (H373L) identified in a 46,XX female with combined 17α-hydroxylase/17,20-lyase deficiency

Background: Defects in cytochrome P450c17 are uncommon forms of congenital adrenal hyperplasia caused by CYP17A1 mutations. An H373L mutation in the CYP17A1 gene has been identified in Japanese and Chinese patients. This mutation impairs 17α-hydroxylase and 17,20-lyase activity. Case: A 23-year-old Korean female (46,XX) presented with absent spontaneous puberty and hypertension. Hormonal findings were consistent with combined 17α-hydroxylase/17,20-lyase deficiency. Very high levels of progesterone and 11-deoxycorticosterone were detected, coincident with normal 17-hydroxysteroid levels. Plasma levels of dehydroepiandrosterone, androstenedione and testosterone were extremely low. Mutation analysis of the CYP17A1 gene identified a homozygous missense mutation changing His (CAC) to Leu (CTC) at codon 373. This mutation is known to completely abolish both 17α-hydroxylase and 17,20-lyase activity. The patient’s nonconsanguineous parents were heterozygous for this mutation. Of note, her serum steroid levels indicated decreased, but still present, 17α-hydroxylase activity in vivo. Conclusion: We detected a homozygous H373L mutation in a patient with combined 17α-hydroxylase/17,20-lyase deficiency. Our findings demonstrate minimally preserved 17α-hydroxylase activity in vivo and contribute to our knowledge of the regional prevalence of this mutation in Northeast Asia.     

A new compound heterozygous mutation in the CYP17A1 gene in a female with 17α-hydroxylase/17,20-lyase deficiency

Abstract

Background: Congenital adrenal hyperplasia due to 17α-hydroxylase/17,20-lyase deficiency (OMIM #202110) is a rare autosomal recessive disorder, which is caused by mutations of the CYP17A1 gene located on chromosome 10q24.3. It has been reported that the type of mutation of the CYP17A1 gene was associated with the extent of 17α-hydroxylase/17,20-lyase deficiency, and the prevalence of common mutation was different among ethnic groups.

Case: A 21-year-old Korean female presented with primary amenorrhea and sexual infantilism, and intermittent hypokalemic episodes. Laboratory test was consistent with hypergonadotropic hypogonadism. The karyotype was 46,XX[20]. Genomic DNA was extracted from peripheral blood leukocytes. All the eight exons of the CYP17A1 gene including flanking regions of introns were amplified by PCR. The mutations of the CYP17A1 gene were detected by direct sequencing. A compound heterozygous mutation was identified; one allele had a missense mutation of c.1118A>T (p.His373Leu), which was reported previously and induced the complete loss of both 17α-hydroxylase/17,20-lyase activity. This mutation has been known to be one of the common mutation types in East Asia. The other allele had a novel 1-bp deletion c.1148delA causing frameshift, premature termination codon (p.Glu383fs) and induced truncated enzymes.

Conclusion: Our experience for stepwise clinical, laboratory and molecular approach would be helpful to diagnose these patients accurately and understand the genetic events in 17α-hydroxylase/17,20-lyase deficiency patients.     

Induction of endometrial cycles and ovulation in a woman with combined 17α-hydroxylase/17,20-lyase deficiency due to compound heterozygous mutations on the P45017α gene

Objective: To describe the case of a Japanese woman with combined 17α-hydroxylase/17,20-lyase deficiency (congenital adrenal hyperplasia type V) and to discuss possible therapeutic procedures in such patients.Design: Case report.Setting: University hospital.Patient(s): A 26-year-old woman with secondary amenorrhea and primary sterility.Intervention(s): Nucleotide sequencing of the P45017α gene (CYP17), induction of endometrial maturation with steroid hormone replacement, and ovulation induction with gonadotropin.Main Outcome Measure(s): Nucleotide sequence of CYP17, endometrial thickness and follicle diameter measured by transvaginal ultrasonography, and histologic evaluation of the endometrium.Result(s): Two different mutations were detected on CYP17: One was a deletion of the phenylalanine codon (TTC) at either amino acid 53 or 54 in exon 1, and the other was a missense mutation with the substitution of histidine (CAC) by leucine (CTC) at position 373 in exon 6. Repeated histologic evaluations performed during treatment with P consistently revealed an unripe endometrium with glands of the early secretory phase and markedly scanty stroma. Ultrasound examination revealed follicular growth and ovulation after gonadotropin administration, but insufficient thickness of the endometrium.Conclusion(s): Ovulation induction was possible in this patient with 17α-hydroxylase/17,20-lyase deficiency, but the endometrial response to steroid hormone replacement was extremely poor.     

CYP17A1 gene mutations and hypertension variations found in 46, XY females with combined 17α-hydroxylase/17, 20-lyase deficiency

The aim of this study was to analyze the structural consequences of the mutations in CYP17A1 gene and their relationship with the variations of clinical manifestations in three patients who presented with complete or partial combined 17α-hydroxylase/17,20-lyase deficiency (17OHD). DNA sequences of the coding exons and intron/exon boundaries of the CYP17A1 gene were analyzed for mutations. In silico analysis with computational three-dimensional model of human P450c17 and multiple alignments analysis were performed to evaluate the spatial conformational changes by missense mutations. Five mutations p.S117fs (c.351_352delCT), p.H373L (c.1184 A>T), p.Y329fs (c.985_987delTACinsAA), p.A82D (c.245 C>A) and p.L209P (c.626 T>C) were identified in three patients, respectively. The novel mutation p.S117fs (c.351_352delCT) has not been reported previously. In silico analysis explained the conformational changes by the described mutations, which resulted in different severe 17OHD. Our studies also suggest that molecular data accompanying with in silico analysis of the CYP17A1 gene are much helpful for the diagnosis, management and genetic counseling of 17OHD.     

A new compound heterozygous mutation in a female with 17α-hydroxylase/17,20-lyase deficiency,slipped capital femoral epiphysis,and adrenal myelolipoma

Abstract

17α-Hydroxylase/17,20-lyase deficiency (17-OHD) is a rare disease caused by mutations of the CYP17A1 gene. Slipped capital femoral epiphysis (SCFE) rarely occurs in adults. There are occasional reports of adrenal myelolipoma (AML) in 17-OHD. A 27-year-old Chinese female (46, XX) visited the hospital for SCFE and presented with continuous hypokalemia, absent spontaneous puberty, and hypertension. Hypergonadotropic hypogonadism was detected. The laboratory tests were consistent with 17-OHD. AML was considered based on the imaging examinations. A mutation analysis of the CYP17A1 gene identified the following compound heterozygous mutation: a frame-shift mutation, i.e. c.985_987delTACinsAA (p.Tyr329fs), that had been reported to be a common mutation in the Chinese population was found in exon 6. Another new nonsense mutation, i.e. c.1270C?>?T (p.Gln424*), that causes a premature termination codon was found in exon 8. Treatment with prednisone had poor efficacy. The administration of 0.75?mg dexamethasone and estradiol/dydrogesterone cyclic treatment significantly improved the patient’s symptoms. For the first time, we report a 17-OHD case accompanied by SCFE, AML, and a novel mutation site in the CYP17A1 gene. We provide insight into the clinical manifestations, genetic analysis, and treatment options of 17-OHD.     

CYP17A1 mutations identified in 17 Chinese patients with 17α-hydroxylase/17,20-lyase deficiency

Context: 17α-hydroxylase deficiency (17OHD) is a relatively rare disease, accounting for about 1% of congenital adrenal hyperplasia cases. The CYP17A1 gene mutation can lead to this disease. Human CYP17A1 gene is located on chromosome 10q24.3. It consists of eight exons encoding 508 amino acids. To date, more than 50 mutations in exons and introns of the CYP17A1 gene have been reported to cause complete or partial 17OHD. Objective: The aim of this study was to investigate the CYP17A1 gene mutation types in 17 Chinese patients, containing 11 complete and six partial 17OHD patients. Setting: We conducted the study in the Department of Obstetrics and Gynecology of Peking Union Medical College Hospital. Patients: Seventeen patients were studied with complete or partial 17OHD. Main outcome measures: The CYP17A1 gene was sequenced and we measured steroid and sex hormone levels. Results: Analysis of the CYP17A1 gene in our patients revealed 12 different kinds of mutation. Two mutations (IVS1-1G>A and L209P) were novel mutations. Mutation c.985_987delTACinsAA (Y329KfsX418) in Exon 6 was the most common mutation in Chinese patients, accounting for 50 percents of the mutant alleles (17/34). Exon 6 was the hot spot since most mutations were detected in this exon (59%, 20/34 alleles). There was no mutation detected in the Exons 4 and 5.     

Isolated mild clitoral hypertrophy may reveal 46,XY disorders of sex development in infancy due to 17βHSD-3 defect confirmed by molecular analysis

Aims.?17-β-Hydroxysteroid dehydrogenase type 3 (17βHSD-3) is expressed exclusively in the testes where it converts Δ4 androstenedione (Δ4) to testosterone (T). Here, we report a patient with a rare mutation at a critical site in HSD17B3 gene leading to deficiency of 17β HSD-3 enzyme.

Methods.?We describe a 3-year old healthy female of consanguineous Lebanese descent, who presented to the endocrine service with isolated mild clitoromegaly. Adrenocorticotropic hormone (ACTH) and human chorionic gonadotrophin (hCG) stimulation tests were performed. Genes for sex-determining region Y (SRY), steroidogenic factor-1 (SF-1) and 17βHSD-3 (HSD17B3) were sequenced.

Results.?The post-hCG stimulation T levels and T/Δ4 ratio was low. Patient had a 46,XY karyotype. Sequence analysis of the HSD17B3 gene revealed a homozygous R80W missense mutation on exon 3. No mutation was found in SRY and SF1 genes. Mullerian structures were not detected on pelvic imaging.

Conclusions.?A low T/Δ4 ratio is indicative of 17βHSD-3 deficiency and associated with isolated clitoromegaly. The R80 site is critical for NADPH binding, thus the mutation at this site leads to 17βHSD-3 deficiency presenting as 46,XY disorder of sex development.     

Genetic defect of a combined 17 α-hydroxylase/17,20-lyase deficiency patient with adrenal crisis

Combined 17 α-hydroxylase/17,20-lyase deficiency (17OHD) is a rare autosomal recessive disease that is a type of congenital adrenal hyperplasia, which results in hypertension, hypokalemia, sexual infantilism, primary amenorrhea in females (46,XX), or pseudohermaphroditism in males (46,XY). It is mainly caused by mutation in the CYP17A1 gene, which encodes a key enzyme in the steroidogenic pathway. However, these patients rarely experience adrenal crisis, due to abnormally high corticosterone levels. Here, we report a 17OHD patient who experienced clinical adrenal crisis on day 1 after gonadectomy. Her (46,XY) genetic defect was c0.715?C?>?T p.Arg239-stop in exon 4 of CYP17A1, which was confirmed by targeted sequence capture/high-throughput sequencing and Sanger sequencing technology. To the best of our knowledge, 17OHD with adrenal crisis has not been reported previously, and the reason why it arose in this patient might have been inappropriate glucocorticoid administration during the perioperative period.     

The Glu331del mutation in the CYP17A1 gene causes atypical congenital adrenal hyperplasia in a 46,XX female

17α-Hydroxylase deficiency is an uncommon type of congenital adrenal hyperplasia (CAH) caused by mutations in the CYP17A1 gene encoding both 17α-hydroxylase and 17,20-lyase, essential for sex steroids production. Main clinical features include lack of pubertal development, hypertension, and hypokalemia. We report the first case of a 46,XX female homozygote for the p.Glu331del mutation in the CYP17A1 gene showing an atypical clinical presentation. She was evaluated the first time for primary amenorrhea and delayed puberty in the presence of low levels of androgens, 17β-estradiol, serum cortisol, and high levels of progesterone and gonadotropins. After puberty, the patient did not show hypocortisolism and/or hypertension. She started estrogen therapy for pubertal induction, followed by ethinylestradiol/gestodene with clinical and biochemical stability during the follow-up period. At the age of 40 years, she developed hypokalemia and clinical signs of hypocortisolism. Oral corticosteroid treatment was started showing a prompt clinical improvement. Modeling analysis predicted the main outcome of the E331 deletion to impair cytochrome b5 binding, according to a major effect on the enzyme’s lyase activity. These data broaden the molecular and clinical spectrum of CAH caused by 17α-hydroxylase deficiency and adds to current genotype–phenotype correlations.     

Primary amenorrhea in two sisters: description of a Mexican family with 17α hydroxylase-17 lyase deficiency caused by arginine – stop mutation

A rare cause of congental adrenal hyperplasia is 17α-hydroxylase deficiency. It results in sexual infantilism, primary amenorrhea in females, pseudohermaphroditism in males, hypertension, and hypokalemia. We studied two female siblings from a rural community in Mexico. The cause of consultation was primary amenorrhea. The proband had low levels of estrogen, progesterone and cortisol. Deoxycorticosterone and corticosterone levels were elevated. The proband was homozygous for a transversion of cytosine to thymine at exon 4 (CGA→TGA), causing a premature stop codon at position 239 (R239X). Analysis of family members showed the presence of this heterozygous mutation in the mother, father and one healthy sibling. In summary, we describe a Mexican family with 17α-hydroxylase deficiency due to R239X mutation.     

Combined 17α-hydroxylase/17,20-lyase deficiency with short stature: case study

Backgrounds: 17α-hydroxylase/17,20-lyase deficiency (17-OHD) is an uncommon form of congenital adrenal hyperplasia. Most patients are tall owing to delayed closure of epiphyses as a result of deficiency of sex hormones.

Methods: We present a 17-OHD case with unusual short stature and reviewed related literature.

Results: A 17-year-old female patient presented with primary amenorrhea, hypertension, hypokalemia and hypergonadotropic hypogonadism (HH). Sequencing of the CYP17A1 gene identified a homozygous c.985_987delTACinsAA in exon 6 that confirmed the diagnosis of 17-OHD. However, her height (148?cm, height standard deviation score [HSDS] ?2.28) was unusually low compared with that of other 17-OHD patients. Levels of growth hormone (GH) and insulin-like growth factor (IGF)-1 were normal, and the GH provocation test excluded the possibility of GH deficiency. She underwent glucocorticoid and sex-hormone replacement therapy, reaching a final height of 152?cm (HSDS ?1.59). These data suggest that tall stature is not a requisite characteristic of 17-OHD. Further studies are needed to clarify the effects of sex hormone on linear bone growth (LBG) in 17-OHD patients.     

Partial 17alpha-hydroxylase/17,20-lyase deficiency–clinical report of five Chinese 46,XX cases

Objectives. To summarize the clinical characteristics of partial 17α-hydroxylase/17,20-lyase deficiency (17OHD) in 46,XX Chinese patients.

Methods. Five cases of 46,XX partial 17OHD from Peking Union Medical College Hospital were studied retrospectively by summarizing and analyzing their clinical data. The molecular pathogenic mechanisms involved are discussed after reviewing the literature.

Results. Both complete and partial 17OHD patients have hypergonadotropic hypogonadism and elevated serum levels of adrenocorticotropic hormone and mineralocorticoids. The clinical characteristics of partial 17OHD are different from those of complete 17OHD; patients with the former having various degrees of estrogenic and androgenic impacts such as the development of breasts and pubic hair, and oligomenorrhea or secondary amenorrhea. Elevated serum progesterone with or without elevated serum 17α-hydroxyprogesterone and recurrent ovarian cysts are typical manifestations of partial 17OHD. Furthermore, hypokalemic hypertension may be absent in partial 17OHD. The 46,XX partial 17OHD should be differentiated from pure gonadal dysgenesis, premature ovarian failure and polycystic ovarian syndrome. It has been reported that specific mutations of the CYP17 gene can cause partial loss of 17α-hydroxylase/17,20-lyase activities or dissociation between the 17α-hydroxylase and the 17,20-lyase functions. Oral contraceptive pills are effective for artificial menstruation, but not for the correction of hormone deficiency. A low dose of cortisol should be prescribed in the presence of hypokalemic hypertension.

Conclusion. The congenital partial 17OHD should be included in the differential diagnosis of menstrual disorders. In these cases, elevated progesterone offers a valuable clue for further investigation.     

Role of CYP2C19 polymorphisms in patients with endometriosis

Aim.?To investigate the association of CYP2C19 genotypes with endometriosis.

Methods.?The study included 100 women who underwent laparotomy or laparoscopy: 50 patients with endometriosis diagnosed with surgery and histopathology, and 50 control subjects who had no evidence of endometriosis during exploratory laparotomy or laparoscopy. Genomic DNA of subjects was extracted from the whole blood using High Pure PCR template preparation kit. Genotyping of CYP2C19 polymorphisms were detected by using a LightCycler CYP2C19 mutation detection kit in a real-time PCR, and were compared between the two groups.

Results.?Logistic regression analyses showed that the CYP2C19*2 heterozygote genotype was associated with a significantly increased risk of endometriosis. The odds ratio of endometriosis for the CYP2C19*2 heterozygote genotype was 3.165 (p = 0.023) compared with the control group. CYP2C19*3 genotype was detected as wild in all subjects in the endometriosis and control groups.

Conclusion.?Our results suggest that CYP2C19*2 heterozygote genotype has higher risk of developing endometriosis. Therefore, CYP2C19*2 allele gene polymorphisms may be associated with genetic susceptibility of endometriosis.     

Two consecutive successful live birth in woman with 17α hydroxylase deficiency by frozen–thaw embryo transfer under hormone replacement endometrium preparation

17α-Hydroxylase deficiency is rare autosomal recessive disorder that manifested by hypertension, hypokalemia, delayed sexual development, primary amenorrhea and infertility. The information regarding infertility care and conception in women with this disorder are extremely limited. We report a 24-year-old Japanese woman with primary amenorrhea who was diagnosed as partial 17α-hydroxylase deficiency caused by homozygous 3?bp deletion in exon 1 of 17α-hydroxylase gene. In vitro fertilization with controlled ovarian stimulation was carried out and all viable embryo were frozen. During ovarian stimulation, serum progesterone levels were markedly elevated, and endometrial growth was impaired. Utilizing frozen-thaw embryo transfer under hormonal replacement (glucocorticoid, estradiol and progesterone), she had successfully given two consecutive live birth. Women with 17α-hydroxylase deficiency with residual ovarian reserve can afford reproductive success by appropriate diagnosis and treatment by assisted reproductive technology.     

17-Hydroxyprogesterone deficiency as a cause of sexual infantilism and arterial hypertension: Laboratory and molecular diagnosis – a case report

The differential diagnosis of hypertension associated with hypokalemia in infancy and adolescence should necessarily include deficiency of the 17α-hydroxylase enzyme, a rare form of congenital adrenal hyperplasia (CAH). In addition to hypertension, the classic syndrome caused by this deficiency is characterized by suppressed production of sex hormones and consequently sexual infantilism. Although rare (1% of all forms of CAH), there appears to be a higher incidence of this syndrome in some population groups. This is a case report on two sisters followed up at the Department of Obstetrics and Gynecology, School of Medicine, Universidade Estadual de Campinas (UNICAMP), who were both found to have the 46,XY genotype with homozygosis for W406R, exon 7 of the CYP17 gene (OMIM 202110). The condition was diagnosed only at puberty when hypergonadotropic hypogonadism resulted in sexual infantilism; however, arterial hypertension had been present since infancy and late diagnosis and lack of timely adequate treatment resulted in complications.     

Polymorphisms in ESR1, ESR2 and HSD17B1 genes are associated with fertility status in endometriosis

Objective.?To investigate whether polymorphisms in genes involved in biosynthesis and signalling of sex steroids influence susceptibility to endometriosis and to infertility associated with it.

Materials and methods.?Patients with endometriosis (n?=?150) and fertile controls (n?=?199) were genotyped for polymorphisms in oestrogen receptor genes ESR1 (rs2234693 – T/C single nucleotide polymorphism (SNP), dinucleotide (TA)_n repeat) and ESR2 (dinucleotide (CA)_n repeat), progesterone receptor gene PGR (rs10895068 – G/A SNP, 306-bp Alu-insertion), 17β-hydroxysteroid dehydrogenase type 1 gene HSD17B1 (rs605059 – A/G SNP), and aromatase gene CYP19A1 (rs10046 – C/T SNP, (TTTA)_n tetranucleotide repeat, 3-bp TCT insertion/deletion polymorphism).

Results.?The HSD17B1 A/G SNP A allele increased overall endometriosis risk and the risk of stage I–II disease, while ESR1 longer (TA)_n repeats only correlated with susceptibility to stage I–II endometriosis. When considering patients' fertility status, HSD17B1 A/G SNP A allele and ESR1 longer (TA)_n repeats were associated with endometriosis accompanied by infertility, while ESR2 shorter (CA)_n repeats were linked with endometriosis without infertility. Other polymorphisms were distributed similarly among patients and controls.

Conclusions.?Genetic variants in ESR1, ESR2, and HSD17B1 genes could modify susceptibility to endometriosis and might influence the fertility status in endometriosis patients.     

Association of anthropometric,androgenic and insulin-related features with polymorphisms in exon 8 of SHBG gene in women with polycystic ovary syndrome

ABSTRACT

Objective: Sex hormone binding globulin (SHBG) levels are often low in women with polycystic ovary syndrome (PCOS). In addition to metabolic and nutritional factors, SHBG levels are determined by genetic polymorphisms in SHBG gene. The aim of this study was to investigate the association of polymorphisms in exon 8 of SHBG gene with anthropometric and biochemical features of women with PCOS.

Design: Prospective, observational study.

Patients: One hundred and ninety-four women with PCOS.

Main outcome measure(s): Genotype analysis of exon 8 in SHBG gene was performed. Serum SHBG, total testosterone, free testosterone, 17-α-hydroxyprogesterone, TSH, PRL, glucose and insulin levels were determined.

Main finding(s): Single nucleotide polymorphism (SNP) E326K located at codon 326 in exon 8 of SHBG gene was identified. Serum SHBG levels decreased significantly with increasing copy number of the variant allele for SNP E326K after adjustment for BMI, androgenic and insulin-related traits. Genotype analysis also revealed SNP, rs6259, located at codon 327 in exon 8 of SHBG gene, which is not associated with SHBG levels.

Conclusion: SNP, E326K, in exon 8 of SHBG gene may influence the metabolism of SHBG independently of BMI, androgenic and insulin-related features in women with PCOS.     

CYP1B1基因多态性与卵巢癌易感性的研究

目的:研究CYP1B1基因外显子2密码子119(G-T)、外显子3密码子432(C-G)多态性与卵巢癌遗传易感性的关系。方法:应用等位基因特异性聚合酶链反应(AS-PCR)法对53例卵巢癌患者和30例对照者进行CYP1B1基因密码子119(G-T)、密码子432(C-G)突变分析,用免疫组化SP法进一步研究雌激素受体(ER)、孕激素受体(PR)的表达,分析其是否受CYP1B1基因多态性的影响。结果:CYP1B1基因密码子432中等位基因C、G在卵巢癌组和对照组分布的差异有统计学意义(P<0.05),其中等位基因G使卵巢癌发病风险增加2.71倍。CYP1B1基因密码子432C/G各基因型分布两组间差异有统计学意义(P<0.01),纯合突变(G/G)基因型、杂合突变(C/G)基因型与野生(C/C)基因型相比,患卵巢癌的危险度分别提高了4.53倍和4.43倍。此外,432G/G、C/G基因型者ER阳性表达率高于432(C/C)基因型,三者间有显著差异(P<0.05)。结论:CYP1B1基因密码子432突变等位基因与卵巢癌的发生有一定关系,突变基因型增加了卵巢癌的发病风险,且与ER的表达相关。