Spectacular advances in molecular genetics have enabled the molecular characterisation of many genetic disorders. The clinical applications include: (i) identification of pre-symptomatic and symptomatic affected individuals (monogenic diseases), allowing for early treatment and prevention of complications, (ii) carrier testing for genetic counselling, (iii) pharmacogenetic testing to guide medical treatment, and (iv) susceptibility testing (in polygenic diseases) to determine the risk of developing future disease. Using the model of congenital adrenal hyperplasia (CAH), direct mutational analysis can be applied to: (i) confirm the diagnosis when hormone assays have been equivocal, which would allow for early treatment and prevention of adrenal crisis, (ii) prenatal diagnosis and prenatal treatment in affected females to prevent or reduce prenatal virilisation, (iii) heterozygote carrier identification for genetic counselling, (iv) novel therapeutic applications to optimise treatment, including adjusting the steroid dose based on consistent genotype-phenotype correlations, so as to reduce the incidence of growth-inhibiting effects of steroid excess. However, molecular analysis can occasionally be complicated by multiple mutations on one allele, which may potentially affect genotype-phenotype correlations. Hence, molecular genetic analysis of CAH may eventually be adopted as a second tier confirmation of the disease, but is unlikely to replace the current first tier screening assays of precursor steroid metabolites proximal to the enzyme deficiency.
Adrenal Hyperplasia, Congenital ; diagnosis ; genetics ; Humans ; Molecular Diagnostic Techniques

OBJECTIVE: Genetic screening and prenatal diagnosis was performed in eighteen families with high risk of 21-hydroxylase deficiency (21-OHD) to provide valuable information for genetic counseling in these affected families. METHODS: First, multiplex ligation-dependent probe amplification (MLPA) combined with nested-PCR based Sanger sequencing was used to detect CYP21A2 gene mutations in probands and their parents of eighteen families, with seven probands had been dead. Second, paternity test was applied to exclude the possibility of maternal genomic DNA contamination, and fetal prenatal diagnosis is based on the mutations found in proband or parents of the family. RESULTS: Ten mutations were identified in these eighteen families, including large fragment deletion, I2G, E3del8bp, I172N, V281L, E6 cluster, L307Ffs, Q318X, R356W and R484Pfs. All probands were caused by homozygous or compound heterozygous mutations of CYP21A2 gene and their parents were carriers. By comparing short tandem repeat sites contamination of maternal genomic DNA was not found in fetal DNA. Prenatal diagnosis showed that five fetus were 21-OHD patients, four fetus were carriers and the other nine fetus were normal. CONCLUSION CYP21A2 gene mutation is the etiology of 21-OHD. Genetic testing of CYP21A2 could assist physicians in 21-OHD diagnosis and provided genetic counseling and prenatal diagnosis for parents who are at risk for having a child with congenital adrenal hyperplasia.
Adrenal Hyperplasia, Congenital ; diagnosis ; genetics ; Female ; Genetic Testing ; Humans ; Mutation ; Pregnancy ; Prenatal Diagnosis ; Steroid 21-Hydroxylase

OBJECTIVETo discuss the genetic diagnosis of congenital adrenal hyperplasia (CAH) and investigate the resource of gene mutations in CAH.

METHODEnzymatic methods with restriction endonucleases that specifically recognized the mutation sites were used to detect the gene mutations in patients with CAH and their relatives. Polymerase chain reaction and direct sequencing were used to identify the mutations in 21-hydroxylase gene, and short tandem repeat (STR) typing was used to determine the sources of the mutations.

RESULTSOne CAH patient had two known mutations in 21-hydroxylase gene, namely the I2g and I172N mutations. The former mutation was inherited from the biological mother and the latter was not inherited.

CONCLUSIONThe 9 common mutations of CAH are also the hotspots for new mutations.

Adrenal Hyperplasia, Congenital ; diagnosis ; genetics ; Gene Deletion ; Genotype ; Humans ; Mutation ; Point Mutation ; Polymerase Chain Reaction ; Steroid 21-Hydroxylase ; genetics

Congenital adrenal hyperplasia is an uncommon diagnosis in routine clinical practice. 21-hydroxylase deficiency, which is its most common subtype, may be diagnosed at birth in a female infant by virilisation or by features of salt wasting in both genders. However, other uncommon subtypes of this condition such as 17-alpha-hydroxylase deficiency, 11-beta-hydroxylase deficiency may present much later in adolescence or adulthood. A high index of suspicion is necessary when evaluating children with hypertension, hypokalaemia, metabolic alkalosis or sexual infantilism.
Adolescent ; Adrenal Hyperplasia, Congenital ; diagnosis ; genetics ; Alkalosis ; diagnosis ; Diagnosis, Differential ; Female ; Humans ; Hypertension ; diagnosis ; Hypokalemia ; diagnosis ; Models, Biological ; Paralysis ; diagnosis ; Sexual Infantilism ; diagnosis ; Steroid 21-Hydroxylase ; metabolism

Congenital lipoid adrenal hyperplasia (CLAH) is caused by mutations to the steroidogenic acute regulatory protein (StAR) gene associated with the inability to synthesize all adrenal and gonadal steroids. Inadequate treatment in an infant with this condition may result in sudden death from an adrenal crisis. We report a case in which CLAH developed in Korean siblings; the second child was prenatally diagnosed because the first child was affected and low maternal serum estriol was detected in a prenatal screening test. To our knowledge, this is the first prenatal diagnosis of the Q258X StAR mutation, which is the only consistent genetic cluster identified to date in Japanese and Korean populations.
46, XY Disorders of Sex Development/*diagnosis/*genetics ; Adrenal Hyperplasia, Congenital/*diagnosis/*genetics ; Adult ; Asian Continental Ancestry Group ; Female ; Genetic Testing/*methods ; Humans ; Korea ; Prenatal Diagnosis/*methods

OBJECTIVE: To identify pathogenic mutations in 25 Chinese pedigrees affected with congenital adrenal hyperplasia (CAH). METHODS: Mutations of the CYP21A2 gene were detected with locus-specific PCR/restriction endonuclease analysis, multiplex ligation-dependent probe amplification assay, and direct sequencing of the entire CYP21A2 gene. Prenatal diagnosis was offered to fetuses at risk for CAH. RESULTS: All 50 alleles of the CYP21A2 gene carried by the 25 pedigrees were successfully delineated. Large deletions and conversions have accounted for 16 (32%) of the alleles, which included 9 entire CYP21A2 gene deletions, 6 chimeric CYP21A1P/CYP21A2 genes, and 1 partial conversion of the CYP21A2 gene. For the remaining 34 alleles, there were 9 micro-conversions and 4 de novo mutations [including a previously unreported c.62G>A (p.Trp21X) mutation]. Prenatal diagnosis was provided for 28 fetuses with a high risk for CAH, among whom 8 were found to be affected. CONCLUSION The detection of CYP21A2 gene mutations can facilitate appropriate genetic counseling and prenatal diagnosis for the affected pedigrees.
Adrenal Hyperplasia, Congenital ; diagnosis ; genetics ; Asian Continental Ancestry Group ; China ; Female ; Humans ; Mutation ; Pedigree ; Pregnancy ; Prenatal Diagnosis ; Steroid 21-Hydroxylase ; genetics

BACKGROUNDSteroid 11beta-hydroxylase deficiency (11beta-OHD), an autosomal recessive inherited disease, accounts for 5% - 8% of congenital adrenal hyperplasia. It was scarcely reported in China. This article reports two Chinese girls with 11beta-OHD.

METHODSThe two patients were sisters and presented with hypertrichosis, skin pigmentation, laryngeal prominence and virilization of external genitalia. The patients were followed up for their clinical symptoms and signs, hormone profile, and adrenal image. The genomic deoxyribonucleic acids of the patients and their parents were isolated. 11beta-hydroxylase gene (CYP11B1) was amplified by polymerase chain reaction and directly sequenced.

RESULTSHormone tests showed that serum cortisol was in the low limit of normal range, whereas the concentrations of adrenocorticotropic hormone, testosterone and progesterone were much higher than those of normal adult females. There were obvious adrenal hyperplasia and advance of bone age. After 11 months of treatment with dexamethasone, the skin pigment became regressed; the breast, uterus and ovary gradually developed and normal menstrual cycle started while the manifestations of virilization did not change. A single point mutation of CYP11B1 (R454C, GGC --> TGC) in all the members of this family was detected. The sisters were homozygous and their parents were heterozygous.

CONCLUSIONSThe clinical manifestation of 11beta-OHD is complicated. The manifestation of virilization could not regress after treatment with dexamethasone. The novel missense mutation of CYP11B1 (R454C, GGC --> TGC) is the pathogenesis of 11beta-OHD at least in some Chinese patients.

Adrenal Hyperplasia, Congenital ; diagnosis ; drug therapy ; genetics ; Child ; Dexamethasone ; therapeutic use ; Female ; Glucocorticoids ; therapeutic use ; Humans ; Male ; Mutation, Missense ; genetics ; Steroid 11-beta-Hydroxylase ; genetics

For the purpose of prenatal diagnosis of CAH, genetic linkage analysis by HLA genotyping with lymphocytes and cultured amniotic cells were performed in a family at risk in which two consecutive children had been affected with SW CAH. In addition, the response of serum 17-OHP to intravenous ACTH was determined in obligate carrier parents, and 17-OHP concentration of amniotic fluid was also measured at 16 weeks of gestation. As might be expected, the baseline levels of 17-OHP in obligate parents were significantly higher than that of normal control. Although the post stimulation response of 17-OHP to ACTH in the mother (I-2) was significantly higher than that of normal control, the post stimulation levels of 17-OHP were in normal range in the father (I-1). The 17-OHP level (5.7 ng/ml) in the amniotic fluid showed intermediate value compared to Pang's report (normal less than 30 ng/ml, CAH greater than 12.0 ng/ml) suggesting heterozygote of the fetus. Genetic linkage analysis by HLA genotyping with cultured amniotic cells revealed heterozygote in their fetus (II-3) who has received one chromosome No,6 containing HLA haplotype A24, B40, Cw3 (normal allele for 21-OH) from the father and the other chromosome No,6 containing HLA haplotype A2, Bw62, Cw4 (mutant allele for 21-OH D) from the mother. In conclusion, attempts to detect heterozygote for 21-OH deficiency by ACTH stimulation test were partially successful and prenatal diagnosis of CAH by the hormone studies in ammiotic fluid requires reliable values in normal, heterozygotes and patients group, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
*Adrenal Hyperplasia, Congenital/*diagnosis/enzymology/genetics ; Adult ; Amniocentesis ; Cells, Cultured ; Female ; Fetal Diseases/*diagnosis/enzymology ; HLA Antigens/analysis ; Heterozygote Detection ; Humans ; Pedigree ; Pregnancy ; *Prenatal Diagnosis ; Steroid Hydroxylases

OBJECTIVETo develop a method for elucidating genetic basis of 21-hydroxylase deficiency.

METHODSSanger sequencing of entire 21-hydroxylase coding gene CYP21A2 was carried out to detect point mutations, and multiplex ligation-dependent probe amplification (MLPA) and locus-specific PCR/enzyme restriction method were used to detect large deletions and conversion mutations.

RESULTSNine children were analyzed. Point mutations of the CYP21A2 gene have been identified as: IVS2 13A/C>G (9 alleles), p.Arg356Trp (1 allele), Cluster E6 (1 allele), p.Gln318X (1 allele), and Prom conv (1 allele). While the former 4 mutations are pathogenic, the role of Prom conv mutation in the pathogenesis was uncertain. Three cases had entire CYP21A2 gene deletions (3 alleles), three had CYP21A1P/CYP21A2 chimeric mutations (3 alleles). The genotypes of all patients were determined. And all of the mutations were inherited from parents.

CONCLUSIONA rational method for detecting point mutations and large deletions/conversions of CYP21A2 gene has been established.

Adrenal Hyperplasia, Congenital ; diagnosis ; genetics ; Alleles ; Base Sequence ; Child ; Child, Preschool ; Female ; Gene Order ; Genotype ; Humans ; Infant ; Male ; Multiplex Polymerase Chain Reaction ; Steroid 21-Hydroxylase ; genetics

Adolescent ; Adrenal Hyperplasia, Congenital ; diagnosis ; genetics ; Adrenal Insufficiency ; Child ; Child, Preschool ; DAX-1 Orphan Nuclear Receptor ; genetics ; Female ; Genetic Diseases, X-Linked ; diagnosis ; genetics ; Humans ; Hypoadrenocorticism, Familial ; Male ; Mutation ; Pedigree ; Phenotype ; Young Adult