Steroid 21-hydroxylase deficiency, due to the genetic impairment of the CYP21 gene, is a major cause of congenital adrenal hyperplasia (CAH). In about 80% of the cases, the defect is related with the transfer of deleterious point mutations from the CYP21P pseudogene to the active CYP21 gene. Sixteen different point mutations have been searched for in 60 Spanish patients with the classic form of CAH and 171 unaffected family members, using selective amplification of the CYP21 gene followed by allele-specific oligonucleotide hybridization (PCR-ASOH) and sequencing analysis. While 31.9% of the disease alleles carry CYP21 deletions or large gene conversions, around 58% of the alleles carry single point mutations. Corresponding segregation of mutations was found in every case indicating that none of them has apparently appeared de novo. The most frequent mutations found in our sample are i2G, V281L, R356W, Q318X, P453S and F306+t, with rates of 30, 14.2, 10, 9.2, 9.2 and 7.5%, respectively. We found similar frequencies for the A and C polymorphism at position 656 (40 and 31.5%, respectively) in wild-type alleles for the i2G mutation. Around 10% of the alleles, for which no mutations were identified by searching for the sixteen previously known mutations, are currently being sequenced and new possible mutations and polymorphisms have been identified.

1.
White PC, New MI, Dupont B: Congenital adrenal hyperplasia. N Engl J Med 1987;316:1519–1524.
2.
New MI, Speiser PW: Genetics of adrenal steroid 21-hydroxylase deficiency. Endocr Rev 1986;7:331–349.
3.
Dupont B, Oberfield SE, Smithwick EM, Lee TD, Levine LS: Close genetic linkage between HLA and congenital adrenal hyperplasia (21-hydroxylase deficiency). Lancet 1977;ii:1309.
4.
Morel Y, David M, Forest MG, Betuel H, Hauptman G, Andre J, Bertrand J, Miller WL: Gene conversions and rearrangement cause discordance between inheritance of forms of 21-hydroxylase deficiency and HLA types. J Clin Endocrinol Metab 1989;68:592–599.
5.
White PC, Vitek A, Dupont B, New MI: Characterization of frequent deletions causing steroid 21-hydroxylase deficiency. Proc Natl Acad Sci USA 1988;85:4436–4440.
6.
Amor M, Parker KL, Globerman H, New MI, White PC: Mutation in the CYP21B gene (Ile-172 to Asn) causes steroid 21-hydroxylase deficiency. Proc Natl Acad Sci USA 1988;85:1600–1604.
7.
Speiser PW, New MI, White PC: Molecular genetic analysis of nonclassic steroid 21-hydroxylase deficiency associated with HLA-B14, DR1. N Engl J Med 1988;319:19–23.
8.
Tusié-Luna MT, Speiser PW, Dumic M, New MI, White PC: A mutation (Pro-30 to Leu) in CYP21 represents a potential nonclassic steroid 21-hydroxylase deficiency allele. Mol Endocrinol 1991;5:685–692.
9.
Chiou SH, Hu MC, Chung BC: A missense mutation at Ile172-Asn or Arg356-Trp causes steroid 21-hydroxylase deficiency. J Biol Chem 1990;265:3549–3552.
10.
Wedell A, Ritzen EM, Haglund-Stengler B, Luthman: Steroid 21-hydroxylase deficiency: Three additional mutated alleles and establishment of phenotype-genotype relationships of common mutations. Proc Natl Acad Sci USA 1992;89:7232–7236.
11.
Helmberg A, Tusié-Luna MT, Tabarelli M, Kofler R, White P: R339H and P453S: CYP21 mutations associated with nonclassic steroid 21-hydroxylase deficiency that are not apparent gene conversions. Mol Endocrinol 1992;6:1318–1322.
12.
Wedell A, Luthman H: Steroid 21-hydroxylase (P450c21): A new allele and spread of mutations through the pseudogene. Hum Genet 1993;91:236–240.
13.
Lajic S, Levo A, Nikoshkov A, Lundberg Y, Partanen J, Wedell A: A cluster of missense mutations at Arg356 of human steroid 21-hydroxylase may impair redox partner interaction. Hum Genet 1997;99:704–709.
14.
Kirby-Keyser L, Porter CC, Donohoue PA: E380D: A novel point mutation of CYP21 in an HLA-homozygous patient with salt-losing congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Hum Mutat 1997;9:181–182.
15.
Globerman H, Amor M, Parker KL, New MI, White PC: Nonsense mutation causing steroid 21-hydroxylase deficiency. J Clin Invest 1988;82:139–144.
16.
Wedell A, Luthman H: Steroid 21-hydroxylase deficiency: Two additional mutations in salt-wasting disease and rapid screening of disease-causing mutations. Hum Mol Genet 1993;2:499–504.
17.
Lajic S, Wedell A: An intron 1 splice mutation and a nonsense mutation (W23X) in CYP21 causing severe congenital adrenal hyperplasia. Hum Genet 1996;98:182–184.
18.
Levo A, Partanen J: Novel nonsense mutation (W302X) in the steroid 21-hydroxylase gene of a Finnish patient with the salt-wasting form of congenital adrenal hyperplasia. Hum Mutat 1997;9:363–365.
19.
Higashi Y, Tanae A, Inoue H, Hiromasa T, Fujii-Kuriyama Y: Aberrant splicing and missense mutations cause steroid 21-hydroxylase [P450(C21)] deficiency in humans: Possible gene conversion products. Proc Natl Acad Sci USA 1988;85:7486–7490.
20.
Speiser PW, Dupont J, Zhu D, Serrat J, Buegeleisen M, Tusié-Luna MT, Lesser M, New MI, White PW: Disease expression and molecular genotype in congenital adrenal hyperplasia due to 21-hydroxylase deficiency. J Clin Invest 1992;90:584–595.
21.
Tajima T, Fujieda K, Nakayama K, Fujii-Kuriyama Y: Molecular analysis of patient and carrier genes with congenital steroid 21-hydroxylase deficiency by using polymerase chain reaction and single strand conformation polymorphism. J Clin Invest 1993;92:2182–2190.
22.
Owerbach D, Crawford YM, Draznin MB: Direct analysis of CYP21B genes in 21-hydroxylase deficiency using polymerase chain reaction amplification. Mol Endocrinol 1990;4:125–131.
23.
Sanger F, Nicklen S, Coulson AR: DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci USA 1997;12:5463–5467.
24.
Lobato MN, Aledo R, Meseguer A: High variability of CYP21 gene rearrangements in Spanish patients with classic form of congenital adrenal hyperplasia. Hum Hered 1998;48:216–225.
25.
Higashi Y, Hiromasa T, Tanae A, Miki T, Nakura J, Kondo T, Ohura T, Ogawa E, Nakayama K, Fujii-Kuriyama Y: Effects of individual mutations in the P-450 (C21) pseudogene on the P450 (C21) activity and their distribution in the patient genomes of congenital steroid 21-hydroxylase deficiency. J Biochem (Tokio) 1991;109:638–644.
26.
White PC: Genetic diseases of steroid metabolism. Vitam Horm 1994;49:131–195.
27.
Nelson DR, Strobel HW: On the membrane topology of vertebrate cytochrome P-450 proteins. J Biol Chem 1988;263:6038–6050.
28.
Mornet E, Crete P, Kuttenn F, Raux-Demay MC, Boue J, White PC, Boue A: Distribution of deletions and seven point mutations on CYP21B genes in three clinical forms of steroid 21-hydroxylase deficiency. Am J Hum Genet 1991;48:79–88.
29.
Strumberg D, Hauffa BP, Horsthemke B, Grosse-Wilde H: Molecular detection of genetic defects in congenital adrenal hyperplasia due to 21-hydroxylase deficiency: A study of 27 families. Eur J Pediatr 1992;151:821–825.
30.
Ezquieta B, Oliver A, Gracia R, Gancedo PG: Analysis of steroid 21-hydroxylase gene mutations in the Spanish population. Hum Genet 1995;96:198–204.
31.
Wilson RC, Wei J, Cheng KC, Mercado AB, New MI: Rapid deoxyribonucleic acid analysis by allele-specific polymerase chain reaction for detection of mutations in the steroid 21-hydroxylase. J Clin Endocrinol Metab 1995;80:1635–1640.
32.
Day JD, Speiser PW, Schulze E, Bettendorf M, Fitness J, Barany F, White PW: Identification of non-amplifying CYP21 genes when using PCR-based diagnosis of 21-hydroxylase deficiency in congenital adrenal hyperplasia (CAH) affected pedigrees. Hum Mol Genet 1996;5:2039–2048.
33.
Owerbach D, Sherman L, Ballard AL, Azziz R: Pro-453 to Ser mutation in CYP21 is associated with nonclassic steroid 21-hydroxylase deficiency. Mol Endocrinol 1992;6:1211–1215.
34.
Wedell A, Thilén A, Martin E, Stengler B, Luthman H: Mutational spectrum of the steroid 21-hydroxylase gene in Sweden: Implications for genetic diagnosis and association with disease manifestation. J Clin Endocrinol Metab 1994;78:1145–1152.
35.
Barbat B, Bogyo A, Raux-Demay MC, Kuttenn F, Boue J, Simon-Bouy B, Serre JL, Mornet E: Screening of CYP21 gene mutations in 129 French patients affected by steroid 21-hydroxylase deficiency. Hum Mutat 1995;5:126–130.
36.
Carrera P, Bordone L, Azzani T, Brunelli V, Garancini MP, Chiumello G, Ferrari M: Point mutation in Italian patients with classic, non-classic, and cryptic forms of steroid 21-hydroxylase deficiency. Hum Genet 1996;98:662–665.
37.
Levo A, Partanen J: Mutation-haplotype analysis of steroid 21-hydroxylase (CYP21) deficiency in Finland. Implications for the population history of defective alleles. Hum Genet 1997;99:488–497.
38.
Araujo M, Sánches M, Susuki L, Guerra G, Farah S, De Mello M: Molecular analysis of CYP21 and C4 genes in Brasilian families with the classical form of steroid 21-hydroxylase deficiency. Braz J Med Biol Res 1996;29:1–13.
39.
Dardis A, Bergada I, Bergada C, Rivarola M, Belgorosky A: Mutations of the steroid 21-hydroxylase gene in an Argentinian population of 36 patients with classical congenital adrenal hyperplasia. J Pediatr Endocrinol Metab 1997;10:55–61.
40.
Miller WL, Auchus RJ, Geller DH: The regulation of 17,20 lyase activity. Steroids 1997;62:133–142.
41.
Rodrigues NR, Dunham I, Yu CY, Carroll MC, Porter RR, Campbell RD: Molecular characterization of the HLA-linked steroid 21-hydroxylase B gene from an individual with congenital adrenal hyperplasia. EMBO J 1987;6:1653–1661.
42.
Ordoñez-Sanchez ML, Ramirez-Jimenez S, Lopez-Gutierrez AU, Riba L, Gamboa-Cardiel S, Cerrillo-Hinojosa M, Altamirano-Bustamante N, Calzada-Leon R, Robles-Valdes C, Mendoza-Morfin F, Tusié-Luna MT: Molecular genetic analysis of patients carrying steroid 21-hydroxylase deficiency in the Mexican population: Identification of possible new mutations and high prevalence of apparent germ-line mutation. Hum Genet 1998;102:170–171.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.