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

Rare forms of congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders due to pathogenic variants in genes encoding enzymes and cofactors involved in adrenal steroidogenesis. Although 21-hydroxylase, 11β-hydroxylase, 3β-hydroxysteroid dehydrogenase type 2, 17α-hydroxylase/17,20-lyase, P450 oxidoreductase, steroidogenic acute regulatory protein, cholesterol side-chain cleavage enzyme deficiencies are considered within the definition of CAH, the term 'CAH' is often used to refer to '21-hydroxylase deficiency (21OHD)' since 21OHD accounts for approximately 95% of CAH in most populations. The prevalence of the rare forms of CAH varies according to ethnicity and geographical location. In most cases, the biochemical fingerprint of impaired steroidogenesis points to the specific subtypes of CAH, and genetic testing is usually required to confirm the diagnosis. Despite there are significant variations in clinical characteristics and management, most data about the rare CAH forms are extrapolated from 21OHD. This review article aims to collate the currently available data about the diagnosis and the management of rare forms of CAH.

17α Hydroxylase/17,20 lyase deficiency: clinical features and genetic insights from a large Turkey cohort

PURPOSE

17α Hydroxylase/17,20 lyase deficiency (17OHD) is a rare form of congenital adrenal hyperplasia, typically diagnosed in late adolescence with symptoms of pubertal delay and hypertension. This study aimed to determine the clinical and laboratory characteristics of 17OHD cases and gather data on disease management.

METHODS

Data from 97 nationwide cases were analyzed using the CEDD-NET web system. Diagnostic, follow-up findings, and final heights of patients were evaluated.

RESULTS

Mean age at admission was 13.54 ± 4.71 years, with delayed puberty as the most common complaint. Hypertension was detected in 65% at presentation; hypokalemia was present in 34%. Genetic analysis revealed Exon 1-6 homozygous deletion as the most frequent mutation, identified in 42 cases. Hydrocortisone replacement was universal; pubertal replacement was administered to 66 cases. Antihypertensive treatment was required in 57 (90%) patients. Thirty-seven cases reached final height, with an average SD of 0.015 in 46,XX and -1.43 in 46,XY. Thelarche and pubarche did not develop properly in some cases despite estradiol treatment.

CONCLUSION

This study represents the largest cohort of pediatric cases of 17-hydroxylase deficiency (17OHD) documented in the literature. Hypertension and hypokalemia can serve as guiding indicators for early diagnosis.The final height is typically considered to be normal. The relationship between genotype and phenotype remains elusive. The initial genetic test for exon 1-6 deletions may be MLPA in our region.

A Case Report of 17α-Hydroxylase Deficiency in Two Saudi Siblings With Different Karyotyping

Congenital adrenal hyperplasia (CAH) consists of variable disorders of sex determination and differentiation. 17α-hydroxylase deficiency (17OHD) is an uncommon form of those disorders, which is typically characterized by hypertension, hypokalemia, failure of puberty, and ambiguous genitalia. The 17α-hydroxylase enzyme is encoded by the CYP17A1 gene and it is required for the synthesis of cortisol and sex steroids. The affected females with 17OHD usually present with primary amenorrhea and delayed puberty, which are associated with hypertension and hypokalemia while male patients might show female external genitalia, pseudohermaphroditism, or variable degrees of ambiguous genitalia with intra-abdominal testes in addition to hypertension and hypokalemia as well. We present two Saudi siblings (19 and 16 years old) who were diagnosed with the rare CAH subtype of 17OHD after presenting with long-standing hypertension, refractory hypokalemia, and failure of puberty. It is interesting that both siblings had biochemical primary adrenal insufficiency; however, both patients did not clinically present with an acute adrenal crisis, which is likely due to the effect of increased levels of deoxycorticosterone. Additionally, although both patients have similar phenotypes and clinical presentations, they have different karyotypes. This again highlights the variability of the manifestations that can result from 17OHD even with an identical mutation in the same family. Both patients were treated successfully with dexamethasone, which has led to the normalization of hypertension, resolution of hypokalemia, and discontinuation of anti-hypertensive medications and potassium supplements after several years of treatment. However, the entire management is quite challenging and requires a multidisciplinary approach regarding difficult issues such as gender identity and assignment and fertility issues in addition to a life-long follow-up.

17 alpha-hydroxylase deficiency: A case report of young Chinese woman with a rare gene mutation

We report a young adult woman with 17 alpha-hydroxylase deficiency (17α-OHD) in Shandong province of China. The patient carried compound heterozygous mutations in the CYP17A1 gene: c.985-987 delinsAA (p.Tyr329LysfsX90) and c.1486C > T (p.Arg496Cys). The patient's hypertension and hypokalemia were resolved after taking medications of glucocorticoid, aldactone, and calcium antagonists.

How Is CYP17A1 Activity Altered in Autism? A Pilot Study to Identify Potential Pharmacological Targets

Background: Increasing evidence exists that higher levels of androgens can be found in individuals with autism. Evidence yields to a susceptible role of Cytochrome P450 17A1 (CYP17A1) with its catalyzation of the two distinct types of substrate oxidation by a hydroxylase activity (17-alpha hydroxylase) and C17/20 lyase activity. However, to what extent steps are altered in affected children with autism versus healthy controls remains to be elucidated. Methods: Urine samples from 48 boys with autism (BMI 19.1 ± 0.6 kg/m², age 14.2 ± 0.5 years) and a matched cohort of 48 healthy boys (BMI 18.6 ± 0.3 kg/m², 14.3 ± 0.5 years) as well as 16 girls with autism (BMI 17.5 ± 0.7 kg/m², age 13.8 ± 1.0 years) and a matched cohort of 16 healthy girls (BMI 17.2 ± 0.8 kg/m², age 13.2 ± 0.8 years) were analyzed for steroid hormone metabolites by gas chromatography-mass spectrometry. Results: The activity of 17-alpha Hydroxylase increased by almost 50%, whereas activity of 17/20 Lyase activity increased by around 150% in affected children with autism. Furthermore, the concentration of Cortisol was higher as compared to the average increase of the three metabolites TH-Corticosterone, 5α-TH-Corticosterone and TH-11β-DH-Corticosterone, indicating, in addition, a stimulation by the CRH-ACTH system despite a higher enzymatic activity. Discussion: As it was shown that oxidative stress increases the 17/20-lyase activity via p38α, a link between higher steroid hormone levels and oxidative stress can be established. However, as glucocorticoid as well as androgen metabolites showed higher values in subjects affected with autism as compared to healthy controls, the data indicate, despite higher CYP17A1 activity, the presence of increased substrate availability in line with the Cholesterol theory of autism.

A rare cause of delayed puberty and primary amenorrhea: 17α-hydroxylase enzyme deficiency

AIM

17α-hydroxylase enzyme deficiency is a rare form of congenital adrenal hyperplasia (CAH) and is caused by mutations in the CYP17A1 gene. The main clinical findings are delayed puberty and primary amenorrhea in girls, and disorders of sex development in boys. It can also cause hypertension and hypokalemia in both genders. In this study, we aimed to present the clinical, laboratory and genetic results of 13 patients from eight different families who were diagnosed with complete 17α-hydroxylase enzyme deficiency.

METHODS

The age, symptoms, anthropometric measurements, blood pressure, Tanner stages, and hormonal and chromosome analysis results at the time of admission were recorded from the medical records of the patients. Whole gene next-generation sequencing of CYP17A1 gene was performed to detect mutations. Multiplex ligation dependent probe amplification (MLPA) method were used to detect deletions in the seven patients who had no point mutation were detected in the CYP17A1 gene.

RESULTS

The average age of the patients at the time of admission was 14.8 (range: 12.9-16.6) years. Also at this time, all patients were in adolescence and were raised as females. The karyotypes of eight patients were 46,XY, and of five patients were 46,XX. Ten patients presented with delayed puberty and primary amenorrhea, one patient with delayed puberty and hypertension, and two patients with hypertension and/or hypokalemia. Hypertension and hypokalemia were detected in nine and seven patients, respectively.

CONCLUSIONS

P450c17 enzyme deficiency should be considered in patients presenting with delayed puberty or primary amenorrhea in the adolescence period and diagnosed with hypergonadotropic hypogonadism, if hypertension and hypokalemia accompany. Early diagnosis prevents the occurrence of important health problems such as hypertension, psychological problems, and gender identity disorders, which affect the majority of these patients.

Genotypic Sex and Severity of the Disease Determine the Time of Clinical Presentation in Steroid 17α-Hydroxylase/17,20-Lyase Deficiency

CONTEXT

Steroid 17α-hydroxylase/17,20-lyase deficiency (17OHD) is characterized by decreased sex steroids and cortisol, and excessive mineralocorticoid action. The clinical symptoms of hypocortisolemia are subtle.

AIM

The clinical, biochemical, and molecular characteristics of patients with 17OHD were evaluated to determine the factors influencing the time of diagnosis and the management.

PATIENTS AND METHODS

Clinical data, steroid profiles by liquid chromatography-tandem mass spectrometry, and Sanger sequencing of the CYP17A1 gene was evaluated in 12 patients with 17OHD diagnosed between 2004 and 2020.

RESULTS

Median age of diagnosis was 13.9 (range: 0.04-29.5) years. Ten of 12 patients had 46,XY karyotype. Except for one boy with partial 17OHD, all patients had female external genitalia hence raised as females. The clinical presentation of 17OHD was earlier (median age: 7 years) in patients, who presented with severe hypertension, atypical genitalia, or positive family history (n = 6, 50%) than those without (median age: 15.3 years; p = 0.0005). The latter group presented with amenorrhea (n = 6, 50%). Steroid profile of patients uniformly showed a typical pattern of 17OHD regardless of the age at diagnosis. Serum gonadotropin concentrations were elevated in patients >12 years (n = 7), normal in pre-adolescents (n = 4), and low in a patient, who had a digenic inheritance of homozygous CYP17A1 and KISS1R mutations.

CONCLUSIONS

Early clinical presentation and diagnosis in 17OHD are associated with symptomatic hypertension in both 46,XX and 46,XY patients or inadequate virilization of external genitalia in 46,XY partial 17OHD. In the absence of these, the clinical presentation is at late pubertal ages at which time amenorrhea and elevated gonadotropins are the hints for diagnosis.

A rare case of 17α-hydroxylase/17, 20-lyase deficiency: Clinical and genetic findings and follow-up outcomes

Here, we reported a case of a 16-year-old Chinese female patient (46, XX) diagnosed as 17α-hydroxylase/17, 20-lyase deficiency (17-OHD) in June 2018 and over 3 years follow-up outcomes; 17-OHD is a rare form of congenital adrenal hyperplasia. The patient presented with primary amenorrhea, underdeveloped secondary sexual characteristics, hypertension and hypokalemia. Hormonal findings revealed decreased estrogen and androgen, increased progesterone, low cortisol concentration and compensatory high adrenocorticotropic hormone level. Mutation analysis of the CYP17A1 gene identified the c.1459_1467del GACTCTTTC homozygous deletion in exon 8, namely, D487_F489del mutation, resulting in the deletion of Aspartate-Serine-Phenylalanine amino acids. The patient's father and mother were all heterozygous carriers of this mutation. The diagnosis and follow-up outcomes provided useful insights to support clinical decision-making and appropriate treatment.

The broad phenotypic spectrum of 17α-hydroxylase/17,20-lyase (CYP17A1) deficiency: a case series

CONTEXT

17α-Hydroxylase/17,20-lyase deficiency (17OHD) caused by mutations in the CYP17A1 gene is a rare form of congenital adrenal hyperplasia typically characterised by cortisol deficiency, mineralocorticoid excess and sex steroid deficiency.

OBJECTIVE

To examine the phenotypic spectrum of 17OHD by clinical and biochemical assessment and corresponding in silico and in vitro functional analysis.

DESIGN

Case series.

PATIENTS AND RESULTS

We assessed eight patients with 17OHD, including four with extreme 17OHD phenotypes: two siblings presented with failure to thrive in early infancy and two with isolated sex steroid deficiency and normal cortisol reserve. Diagnosis was established by mass spectrometry-based urinary steroid profiling and confirmed by genetic CYP17A1 analysis, revealing homozygous and compound heterozygous sequence variants. We found novel (p.Gly111Val, p.Ala398Glu, p.Ile371Thr) and previously described sequence variants (p.Pro409Leu, p.Arg347His, p.Gly436Arg, p.Phe53/54del, p.Tyr60IlefsLys88X). In vitro functional studies employing an overexpression system in HEK293 cells showed that 17,20-lyase activity was invariably decreased while mutant 17α-hydroxylase activity retained up to 14% of WT activity in the two patients with intact cortisol reserve. A ratio of urinary corticosterone over cortisol metabolites reflective of 17α-hydroxylase activity correlated well with clinical phenotype severity.

CONCLUSION

Our findings illustrate the broad phenotypic spectrum of 17OHD. Isolated sex steroid deficiency with normal stimulated cortisol has not been reported before. Attenuation of 17α-hydroxylase activity is readily detected by urinary steroid profiling and predicts phenotype severity.

SIGNIFICANCE STATEMENT

Here we report, supported by careful phenotyping, genotyping and functional analysis, a prismatic case series of patients with congenital adrenal hyperplasia due to 17α-hydroxylase (CYP17A1) deficiency (17OHD). These range in severity from the abolition of function, presenting in early infancy, and unusually mild with isolated sex steroid deficiency but normal ACTH-stimulated cortisol in adult patients. These findings will guide improved diagnostic detection of CYP17A1 deficiency.

Novel mutations of the CYP17A1 gene in four Chinese 46,XX cases with partial 17a-hydroxylase/17,20-lyase deficiency

The condition 17a-Hydroxylase/17,20-lyase deficiency (17-OHD) is a rare kind of congenital adrenal hyperplasia (CAH) characterized by failure to synthetize cortisol, adrenal androgens and gonadal steroids. Partial deficiency is much rarer, presenting with subtler symptoms. In this study, we summarized the clinical characteristics and identified the underlying gene mutation in four Chinese 46,XX patients with partial 17-OHD. Mutational analysis of the CYP17A1 gene was performed by polymerase chain reaction (PCR) and Sanger sequencing. Clinical and hormonal findings in these patients were consistent with typical manifestations of partial 17-OHD. All patients were found to have a compound heterozygous mutation of the CYP17A1 gene, with five mutations identified. Among them, c.887 T > C(p. I296T), c.1019G > A(p. R340H) and c.1346G > A(p. R449H) were novel missense mutations. In conclusion, we identified three novel missense mutations of the CYP17A1 gene from four patients with partial 17-OHD deficiency. Genotype-phenotype correlation analysis revealed that these novel mutations can lead to partial 17-OHD. Our findings thus provide novel insight into the clinical evaluations and molecular basis of 17-OHD.

Clinical, biochemical and genetic characteristics of children with congenital adrenal hyperplasia due to 17α-hydroxylase deficiency

Objectives Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder, that could rarely be due to 17 α-hydroxylase deficiency (17αOHD) and/or 17,20 lyase deficiency. Mutation of CYP17A1 gene causes deficiency of glucocorticoids and androgens but excess of mineralocorticoids. Lack of genital ambiguity in most children causes a delay in diagnosis even until puberty. Classical presentation with hypertension and hypokalemia is often not encountered. We intended to study the clinical, biochemical and genetic characteristics of children diagnosed with CAH due to 17αOHD. Methods Three children who were diagnosed with CAH due to 17αOHD in our institute and on follow up were included in this retrospective study. Clinical, biochemical and genetic characteristics of these children were retrieved and studied from electronic medical records. Results Two children were genetic females and one was genetic male, but all three were raised as females. All had hypertension at diagnosis except one but none had hypokalemia. All of them had mutation in the CYP17A1 gene. The two females responded well to oestrogen and progesterone and had adequate estrogenization clinically. Conclusions Even though CAH due to 17αOHD is quite rare, it should be considered while evaluating young individuals with hypogonadism, hypertension with or without hypokalemia. Lack of genital ambiguity and absence of classical signs at presentation does not rule out this not so uncommon condition and warrants follow up.

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

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.

A Rare Cause of Congenital Adrenal Hyperplasia: Clinical and Genetic Findings and Follow-up Characteristics of Six Patients with 17-Hydroxylase Deficiency Including Two Novel Mutations

OBJECTIVE

17α-hydroxylase/17,20 lyase deficiency (17OHD) is a rare form of congenital adrenal hyperplasia (CAH), characterized by hypertension and varying degrees of ambiguous genitalia and delayed puberty. The disease is associated with bi-allelic mutations in the CYP17A1 gene located on chromosome 10q24.3. We aimed to present clinical and genetic findings and follow-up and treatment outcomes of 17OHD patients.

METHODS

We evaluated six patients with 17OHD from five families at presentation and at follow up. Standard deviation score of all auxological measurements was calculated according to national data and karyotype status. CYP17A1 gene sequence alterations were investigated in all patients.

RESULTS

The mean (±standard deviation) age of patients at presentation and follow-up time was 14.6±4.2 and 5.0±2.7 years respectively. Five patients were referred to us because of delayed puberty and primary amenorrhea and four for hypertension. One novel single nucleotide insertion leading to frame shift and another novel variant occurring at an ultra rare position, leading to a missense change, are reported, both of which caused 17OHD deficiency. Steroid replacement was started. The three patients with 46,XY karyotype who were raised as females underwent gonadectomy. Osteoporosis was detected in five patients. Four patients needed antihypertensive treatment. Improvement in osteoporosis was noted with gonadal steroid replacement and supportive therapy.

CONCLUSION

17OHD, a rare cause of CAH, should be kept in mind in patients with pubertal delay and/or hypertension. Patients with 46,XY who are raised as females require gonadectomy. Due to late diagnosis, psychological problems, gender selection, hypertension and osteoporosis are important health problems affecting a high proportion of these patients.

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.

Diagnostic yield of targeted gene panel sequencing to identify the genetic etiology of disorders of sex development

Disorders of sex development (DSD) vary phenotypically and are caused by a number of genetic etiologies. This study investigated the genetic etiology of DSD patients using targeted exome sequencing of 67 known DSD-associated genes in humans. This study included 37 patients with 46, XY DSD and seven patients with 46, XX DSD. We identified known pathogenic mutations or deletion in nine (20.5%) patients in the AR, CYP17A1, SRD5A1, and DMRT1/2 genes. Novel variants were identified in nine patients (20.5%) in the AR, ATRX, CYP17A1, CHD7, MAP3K1, NR5A1, and WWOX genes. Among them, four patients harbored pathogenic or likely pathogenic variants, while the remaining five patients (11.4%) had variants of uncertain significance. We were able to make a genetic diagnosis in 29.5% of patients with pathogenic or likely pathogenic mutations. Targeted exome sequencing is an efficient tool to improve the diagnostic yield of DSD, despite its phenotypic and genetic heterogeneity.

17α-HYDROXYLASE/17, 20-LYASE DEFICIENCY: CLINICAL AND MOLECULAR CHARACTERIZATION OF EIGHT CHINESE PATIENTS

OBJECTIVE

17α-hydroxylase/17, 20-lyase deficiency (17OHD) is caused by mutations in the cytochrome P450 17A1 (CYP17A1) gene. To better understand 17OHD, a rare disease, we described the clinical features and performed CYP17A1 gene analysis in 8 affected Chinese patients.

METHODS

Patients with complete (7/8) or partial (1/8) 17OHD were derived from 6 families. The diagnosis was established according to their clinical, biochemical, hormonal, and radiological characteristics. Long-term follow-up of some patients was also designed.

RESULTS

Patients with 17OHD suffered from varying degrees of hypokalemia and hypertension. Symptoms in female patients with partial 17OHD manifested as secondary amenorrhea, recurrent ovarian cysts, elevated estradiol level, and lower follicle-stimulating hormone and luteinizing hormone levels; primary amenorrhea was typical in patients with complete 17OHD. Adrenal masses and decreased bone mineral density (BMD) were discovered in 2 patients, respectively. During long-term follow-up, 4 patients developed low BMD, while 3 individuals underwent respiratory infections and recurrent urinary tract infections. CYP17A1 gene analysis revealed 7 different kinds of mutation, including 1 novel mutation, L266V.

CONCLUSION

The clinical characteristics of partial 17OHD were different from those of complete 17OHD. Low BMD and infections were common in patients with 17OHD on long-term steroid treatment. Seven mutations were identified in the CYP17A1 gene, and 1 was novel.

ABBREVIATIONS

ACTH = adrenocorticotropic hormone BMD = bone mineral density CAH = congenital adrenal hyperplasia CT = computed tomography DEXA = dual-energy X-ray absorptiometry DEX = dexamethasone 17OHD = 17α-hydroxylase/17, 20-lyase deficiency.

Gonadal malignancy in 202 female patients with disorders of sex development containing Y-chromosome material

The objective of this study was to examine risks for gonadal malignancy in a large sample of adult female patients with disorders of sex development (DSD). A retrospective-observational study was conducted from July 1992 to March 2015 and 202 women with DSD were enrolled. Tumor risks for different types of DSD were measured. We found that the patients' total gonadal-malignancy risk was 18.3% (37/202). Tumors included gonadoblastoma (n = 11), seminoma (n = 8), dysgerminoma (n = 5), choriocarcinoma (n = 1), sertoli cell tumors (n = 11), and leydig cell tumors (n = 1). The incidence of gonadal malignancy in patients with complete androgen insensitivity syndrome (CAIS), pure 46, XY gonadal dysgenesis, 45 X/46 XY mixed gonadal dysgenesis, 17α-hydroxylase/17, 20-lyase deficiency and partial androgen insensitivity syndrome (PAIS) were 27.1% (13/48), 22.4% (15/67), 10.9% (5/46), 10% (2/20) and 9.5% (2/21), respectively. Our results suggest that the incidence of gonadal malignancy increases with age for female patients with Y-chromosome material. Upon diagnoses, immediate, prophylactic gonadectomies should be considered for adult female patients with DSD containing Y chromosome material if they cannot receive regular follow-ups.

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.

New, recurrent, and prevalent mutations: Clinical and molecular characterization of 26 Chinese patients with 17alpha-hydroxylase/17,20-lyase deficiency

BACKGROUND

Combined 17alpha-hydroxylase/17,20-lyase deficiency (17OHD), caused by mutations in the CYP17A1 gene, is a rare autosomal recessive form of congenital adrenal hyperplasia and characterized by hyporeninemic hypokalemic hypertension, primary amenorrhea and absence of secondary sexual characteristics.

SUBJECTS AND METHODS

Twenty six 17OHD subjects from 23 Chinese families were recruited. The CYP17A1 gene was sequenced and 17alpha-hydroxylase/17,20-lyase enzymatic activities were assessed in vitro.

RESULTS

Eight CYP17A1 mutations were identified in 23 patients. Of eight mutations, c.985_987delinsAA/p.Y329Kfs and c.1460_1469del/p.D487_F489del mutations accounted for 60.8% (28/46) and 21.7% (10/46) of the mutant alleles, respectively. The enzymatic activities for both mutations were completely abolished. We also identified three novel mutations c.971_972insG/p.K325Afx, c.1464_1466delT/p.F489Sfx and c.1386G>T/p.R462S. The enzymatic activities for c.971_972insG/p.K325Afx and c.1464_1466delT/p.F489Sfx mutations were almost completely abolished, whereas the mutation c.1386G>T/p.R462S only resulted in partial reduction of 17alpha-hydroxylase (34.6%) and 17,20 lyase activities (27.0%), which is correlated with the partial 17OHD phenotype in this patient.

CONCLUSION

The c.985_987delinsAA/p.Y329Kfs and c.1460_1469del/p.D487_F489del mutations are prevalent in Chinese 17OHD patients. The genetic defects are well correlated with the phenotypes in both complete and partial forms of 17OHD.

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.

Congenital Adrenal Hyperplasia due to 17-alpha-hydoxylase/17,20-lyase Deficiency Presenting with Hypertension and Pseudohermaphroditism: First Case Report from Oman

This is the first report of congenital adrenal hyperplasia (CAH) due to combined 17α-hydroxylase/17,20 lyase deficiency in an Omani patient who was initially treated for many years as a case of hypertension. CAH is an uncommon disorder that results from a defect in steroid hormones biosynthesis in the adrenal cortex. The clinical presentation depends on the site of enzymatic mutations and the types of accumulated steroid precursors. A 22-year-old woman who was diagnosed to have hypertension since the age of 10 years who was treated with anti-hypertensive therapy was referred to the National Diabetes and Endocrine Centre, Royal Hospital, Oman. The patient also had primary amenorrhea and features of sexual infantilism. Full laboratory and radio-imaging investigations were done. Adrenal steroids, pituitary function and karyotyping study were performed and the diagnosis was confirmed by molecular mutation study. Laboratory investigations revealed adrenal steroids and pituitary hormones profile in addition to 46XY karyotype that are consistent with the diagnosis of CAH due to 17α-hydroxylase deficiency. Extensive laboratory workup revealed low levels of serum cortisol (and its precursors 17α-hydroxyprogesterone and 11-deoxycortisol), adrenal androgens (dehydroepiandrosterone sulfate and androstenedione), and estrogen (estradiol); and high levels of mineralocorticoids precursors (11-deoxycorticosterone and corticosterone) with high levels of ACTH, FSH and LH. Mutation analysis revealed CYP17A1-homozygous mutation (c.287G>A p.Arg96Gln) resulting in the complete absence of 17α-hydroxylase/17,20-lyase activity. The patient was treated with dexamethasone and ethinyl estradiol with cessation of anti-hypertensive therapy. A review of the literature was conducted to identify previous studies related to this subtype of CAH. This is the first biochemically and genetically proven case of CAH due to 17α-hydroxylase/17,20-lyase deficiency in Oman and in the Arab World described in the literature.

A review of the literature on common CYP17A1 mutations in adults with 17-hydroxylase/17,20-lyase deficiency, a case series of such mutations among Koreans and functional characteristics of a novel mutation

OBJECTIVE

17α-hydroxylase/17,20-lyase deficiency is a rare form of congenital adrenal hyperplasia, characterized by hypertension and sexual infantilism and caused by loss-of-function mutations in CYP17A1. This study investigated the clinical and molecular characteristics of six adults with 17α-hydroxylase/17,20-lyase deficiency and the functional consequences of a novel CYP17A1 mutation.

MATERIALS AND METHODS

Six phenotypic females, three with 46,XY and three with 46,XX karyotypes, presented with primary amenorrhea and hypertension. All had elevated levels of plasma adrenocorticotropic hormone, serum gonadotropin, progesterone, and 11-deoxycorticosterone, and reduced testosterone and dehydroepiandrosterone sulfate (DHEA-S). All coding exons and flanking intronic sequences of CYP17A1 were directly sequenced using genomic DNA. Wild-type and mutant CYP17A1 cDNAs were inserted into the pcDNA3.1/V5-His-P450c17 vector, and transiently expressed in COS-7 cells. This was followed by an assessment of 17α-hydroxylase and 17,20-lyase activities by measuring the conversions of progesterone to 17-hydroxyprogesterone and 17-hydroxypregnenolone to DHEA.

RESULTS

The mutation analysis identified one patient with compound heterozygosity for p.H373L and p.W406L, one with compound heterozygosity for p.H373L and p.A174E, three with compound heterozygosity for p.Y329fs and p.H373L, and one with homozygosity for p.H373L. An in vitro functional analysis of the novel p.W406L mutation revealed a complete loss of 17α-hydroxylase/17, 20-lyase activities.

CONCLUSIONS

p.H373L was the most common mutation among these Korean patients, consistent with the high allele frequency of p.H373L in Chinese and Japanese populations, suggesting possible founder effects in Asian countries. The novel p.W406L mutation caused a complete loss of both catalytic activities, indicating that this amino acid is critical for P450c17 function.