p.H62L, a Rare Mutation of the CYP21 Gene Identified in Two Forms of 21-Hydroxylase Deficiency

Objective: Congenital adrenal hyperplasia (CAH) shows a range of severity which is explained in part by the different mutations of the CYP21 gene. To better understand the incomplete concordance between genotype and phenotype in CAH the role of the sensitizing N363S polymorphism of the glucocorticoid receptor (GR) was examined in CAH patients. Design: CAH patients were screened for N363S. Laboratory findings and clinical characteristics of carriers and non-carriers were analyzed retrospectively. Methods: The CYP21 gene of 200 CAH patients was analyzed by allele-specific PCR. The GR gene was tested for N363S by PCR followed by restriction fragment length polymorphism. Antropometric data (height, weight), degree of intrauterine virilization, hormone concentrations (17-OH-progesterone, dehydroepiandrosterone (DHEA), aldosterone, testosterone, plasma renin activity), substitution doses and clinical course were analyzed. Results: The carrier frequency of N363S in CAH patients was equivalent to that of the general Hungarian population (6% vs 7.8%). Interestingly, none of the non-classical CAH (NC-CAH) patients were carriers of the polymorphism. Carrier girls had milder genital virilization than mutation-matched non-carrier controls. There was no significant difference between the carriers and non-carriers in either the substitution doses, the hormonal, or the auxiological parameters. Conclusions: The association of sensitizing the GR variant with impaired cortisol production in CAH might be compensatory in mild NC-CAH and may prevent severe intrauterine virilization in classical form. Although the exact role of N363S in extrauterine life should be further investigated, the consideration of certain genetic polymorphisms of CAH patients may lead to better, individualized therapeutic regimes.

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Three Novel Mutations in CYP21 Gene in Brazilian Patients with the Classical Form of 21-Hydroxylase Deficiency Due to a Founder Effect

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2001-011939 ◽

2002 ◽

Vol 87 (9) ◽

pp. 4314-4317 ◽

Cited By ~ 38

Author(s):

Ana Elisa C. Billerbeck ◽

Berenice B. Mendonca ◽

Emilia M. Pinto ◽

Guiomar Madureira ◽

Ivo J. P. Arnhold ◽

...

Keyword(s):

Founder Effect ◽

Novel Mutations ◽

Hydroxylase Deficiency ◽

Classical Form ◽

Cyp21 Gene ◽

21 Hydroxylase Deficiency

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Mutation of IVS2 –12A/C>G in Combination with 707–714delGAGACTAC in the CYP21 Gene Is Caused by Deletion of the C4-CYP21 Repeat Module with Steroid 21-Hydroxylase Deficiency

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2003-030047 ◽

2003 ◽

Vol 88 (6) ◽

pp. 2726-2729 ◽

Cited By ~ 12

Author(s):

Hsien-Hsiung Lee ◽

Shwu-Fen Chang ◽

Fuu-Jen Tsai ◽

Li-Ping Tsai ◽

Ching-Yu Lin

Keyword(s):

Congenital Adrenal Hyperplasia ◽

Donor Site ◽

Adrenal Hyperplasia ◽

Hydroxylase Deficiency ◽

Aberrant Splicing ◽

Cyp21 Gene ◽

Pcr Product ◽

Intergenic Recombination ◽

21 Hydroxylase Deficiency

More than 90% of the cases of congenital adrenal hyperplasia are caused by mutations of the CYP21 gene. Approximately 75% of the defective CYP21 genes are generated through intergenic recombination, termed apparent gene conversion, from the neighboring CYP21P pseudogene. Among them, mutation of the aberrant splicing donor site of IVS2 –12A/C>G at nucleotide (nt) 655 is believed to be a result derived from this mechanism and is the most prevalent case among all ethnic groups. However, mutation of 707–714delGAGACTAC rarely exists alone, although this locus is a distance of 53 nt away from IVS2 –12A/C>G. From the molecular characterization of the mutation of IVS2 –12A/C>G combined with 707–714delGAGACTAC in patients with congenital adrenal hyperplasia, we found that it appeared to be in a 3.2-rather than a 3.7-kb fragment generated by Taq I digestion in a PCR product of the CYP21 gene. Interestingly, the 5′ end region of such a CYP21 haplotype had CYP21P-specific sequences. Our results indicate that the coexistence of these two mutations is caused by deletion of the CYP21P, XA, RP2, and C4B genes and intergenic recombination in the C4-CYP21 repeat module. Surprisingly, this kind of the haplotype of the mutated CYP21 gene has not been reported as a gene deletion.

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H28+C Insertion in the CYP21 Gene: A Novel Frameshift Mutation in a Brazilian Patient with the Classical Form of 21-Hydroxylase Deficiency

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.86.12.8113 ◽

2001 ◽

Vol 86 (12) ◽

pp. 5877-5880 ◽

Cited By ~ 14

Author(s):

Ivy F. Lau ◽

Fernanda C. Soardi ◽

Sofia H. V. Lemos-Marini ◽

Gil Guerra Jr. ◽

Maria Tereza M. Baptista ◽

...

Keyword(s):

Frameshift Mutation ◽

Hydroxylase Deficiency ◽

Classical Form ◽

Cyp21 Gene ◽

Brazilian Patient ◽

21 Hydroxylase Deficiency

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Adrenal 21-hydroxylase gene mutations in Slovenian hyperandrogenic women: evaluation of corticotrophin stimulation and HLA polymorphisms in screening for carrier status

Acta Endocrinologica ◽

10.1530/eje.0.1410132 ◽

1999 ◽

pp. 132-139 ◽

Cited By ~ 13

Author(s):

V Dolzan ◽

J Prezelj ◽

B Vidan-Jeras ◽

K Breskvar

Keyword(s):

Molecular Analysis ◽

Gene Mutations ◽

Hla Typing ◽

Carrier Status ◽

Acth Stimulation ◽

Adrenal Androgen ◽

Hydroxylase Deficiency ◽

Predictive Values ◽

Cyp21 Gene ◽

21 Hydroxylase Deficiency

OBJECTIVE: To study the incidence of 21-hydroxylase deficiency in Slovenian hyperandrogenic women, at the gene level. Previous endocrine studies indicated large differences in the incidence of 21-hydroxylase deficiency in hyperandrogenic women. The predictive values of the 17-hydroxyprogesterone (17-OHP) response to ACTH stimulation and of HLA typing in screening for carrier status were re-evaluated. DESIGN: Molecular analysis of CYP21 gene, ACTH stimulation and human leucocyte antigen (HLA) typing were performed in 83 consecutive Slovenian hyperandrogenic women. MEASUREMENTS: Cortisol and 17-OHP concentrations were measured at baseline and 60 min after ACTH stimulation. Basal adrenal androgen concentrations were also measured. RESULTS: None of 83 hyperandrogenic patients was affected with non-classical 21-hydroxylase deficiency, but 12 of 81 patients (14.8%) had high concentrations of 17-OHP after stimulation, indicative of carrier status. The increase in 17-OHP concentrations could be explained by a carrier status for CYP21 gene mutations in only three of 12 patients (25%), whereas seven of 69 patients (10. 1%) with normal concentrations of 17-OHP after stimulation were found to be carriers of CYP21 gene mutations, indicating low positive predictive values of ACTH stimulation as a screening test for carriers of 21-hydroxylase deficiency. In total, 11 carriers were identified among 83 patients: seven CYP21 gene deletions/conversions, two Gln(318)Stop and one Val(281)Leu mutation and one gene conversion extending from exon 4 to exon 7 were found. The association between Val(281)Leu mutation and HLA-B14 antigen was confirmed in this Slovenian population. CONCLUSIONS: Basal or ACTH-stimulated 17-OHP concentrations are not a good indicator of the carrier status for 21-hydroxylase deficiency among Slovenian hyperandrogenic patients. Reliable screening for carriers of 21-hydroxylase deficiency is possible only by molecular analysis of the CYP21 gene.

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Phenotype-Genotype Correlation in 56 Women with Nonclassical Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.86.1.7131 ◽

2001 ◽

Vol 86 (1) ◽

pp. 207-213 ◽

Cited By ~ 58

Author(s):

Catherine Deneux ◽

Véronique Tardy ◽

Anne Dib ◽

Etienne Mornet ◽

Line Billaud ◽

...

Keyword(s):

Congenital Adrenal Hyperplasia ◽

Phenotypic Expression ◽

Complete Analysis ◽

Primary Amenorrhea ◽

Adrenal Hyperplasia ◽

Hydroxylase Deficiency ◽

Cyp21 Gene ◽

Severe Mutation ◽

21 Hydroxylase Deficiency ◽

Genotype Correlation

Complete analysis of the CYP21 gene was performed in 56 unrelated French women with symptomatic nonclassical congenital adrenal hyperplasia. The mutational spectrum and the phenotype-genotype correlation were examined. The overall predominant mutation was V281L, which was present on 51% of alleles and in 80% of women. Three novel mutations were found: L317M, R435C, and a 5′-end gene conversion. Sixty-three percent of the women were carrying a severe mutation of the CYP21 gene, and hence risk giving birth to children with a classical form of the disease. In such cases, screening for heterozygosity in the partner is crucial. Potential genotype/phenotype correlations were examined by classifying the patients into three groups according to the CYP21 allelic combinations: A (mild/mild), B (mild/severe), and C (severe/severe). Primary amenorrhea was more frequent, and mean basal and stimulated 17-hydroxyprogesterone levels were higher in compound heterozygotes for mild and severe mutations (group B) compared with women with two mild mutations (group A), but there was a considerable overlap for individual values. Surprisingly, in two women, a severe mutation was found on both alleles (group C). Therefore, the phenotype cannot be accurately predicted from the genotype. Variability in phenotypic expression may be conditioned by mechanisms other than genetic heterogeneity at the CYP21 locus.

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Mutations of the CYP21 Gene in Nonclassical Steroid 21-Hydroxylase Deficiency in Japan.

Endocrine Journal ◽

10.1507/endocrj.45.493 ◽

1998 ◽

Vol 45 (4) ◽

pp. 493-497 ◽

Cited By ~ 14

Author(s):

TOSHIHIRO TAJIMA ◽

KENJI FUJIEDA ◽

JUN NAKAE ◽

ATUSHI MIKAMI ◽

GORDON B. CUTLER

Keyword(s):

Hydroxylase Deficiency ◽

Cyp21 Gene ◽

21 Hydroxylase Deficiency

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Analysis of the Chimeric CYP21P/CYP21 Gene in Steroid 21-Hydroxylase Deficiency

Clinical Chemistry ◽

10.1093/clinchem/46.5.606 ◽

2000 ◽

Vol 46 (5) ◽

pp. 606-611 ◽

Cited By ~ 16

Author(s):

Hsien-Hsiung Lee ◽

Jan-Gowth Chang ◽

Chang-Hai Tsai ◽

Fuu-Jen Tsai ◽

Hsiang-Tai Chao ◽

...

Keyword(s):

Congenital Adrenal Hyperplasia ◽

Direct Method ◽

Pcr Amplification ◽

Chimeric Gene ◽

Wild Type ◽

Adrenal Hyperplasia ◽

Specific Primer ◽

Hydroxylase Deficiency ◽

Cyp21 Gene ◽

21 Hydroxylase Deficiency

Abstract Background: A single nonfunctional chimeric gene with its 5′ and 3′ ends corresponding to CYP21P and CYP21, respectively, is caused by unequal gene crossover in the CYP21 genes during meiosis. The presence of the chimeric CYP21P/CYP21 molecule can not be detected by conventional PCR methods and therefore may be lost in PCR amplification. This leads to a false result and diagnostic discordance. Methods: We developed a rapid and direct method to detect a chimeric CYP21P/CYP21 gene that uses a 3′-specific primer for the CYP21 gene and two different 5′ primers for both CYP21 and CYP21P to amplify the wild-type CYP21 and the chimeric CYP21P/CYP21 genes. A secondary PCR that can differentiate the chimeric from the wild-type gene was also performed. The PCR product was directly analyzed on agarose gel. Results: After careful titration, we found that earlier failure to detect the chimeric CYP21P/CYP21 gene could be caused by unequal concentrations of two independent alleles as the PCR template or by the lack of primers to amplify chimeric molecules. We successfully amplified the chimeric gene using our improved method. Conclusions: The chimeric CYP21P/CYP21 is present in a large portion of congenital adrenal hyperplasia patients. By adding a CYP21P/CYP21-specific primer, we were able to amplify and detect both homozygous and heterozygous chimeric genes. Therefore, our new PCR-based assay is a more effective way to analyze congenital adrenal hyperplasia mutations.

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