Development and evaluation of a candidate reference measurement procedure for detecting 17α-hydroxyprogesterone in dried blood spots using isotope dilution liquid chromatography tandem mass spectrometry.

17α-Hydroxyprogesterone (17α-OHP) quantification in dried blood spots (DBS) is essential for newborn screening for congenital adrenal hyperplasia (CAH), which is challenging due to its low physiological concentration. The high false-positive rates of immunoassays necessitate the development of more accurate methods. Liquid chromatography tandem mass spectrometry (LC-MS/MS) offers increased specificity and sensitivity, yet standardized procedures for 17α-OHP measurement are required for clinical application. A candidate reference measurement procedure (cRMP) using isotope dilution LC-MS/MS was developed for 17α-OHP quantification in DBS. By utilizing stable isotope-labeled D8-17α-OHP as an internal standard, the cRMP was optimized, covering sample preparation, calibration, and LC-MS/MS analysis. The method performance was validated across several parameters, including precision, accuracy, specificity, detection limits, and matrix effects. Clinical applicability was further assessed through the establishment of reference intervals for healthy newborns. The developed cRMP exhibited a linear range of 1.00 to 80.00 ng/mL for 17α-OHP, with detection and quantification limits of 0.14 ng/mL and 0.52 ng/mL, respectively. Inter- and intraday precision demonstrated coefficients of variation within 1.27 to 5.69%. The recovery rates and matrix effects were well within acceptable limits, ensuring method reliability. Clinical application showed distinct reference intervals for healthy newborns that were unaffected by sex but influenced by weight and gestational age. This method significantly enhances CAH diagnostic accuracy in newborns, providing a valuable tool for clinical laboratories and improving newborn screening program standardization and traceability.

Successful Pregnancy in Isolated 17,20-lyase Deficiency Without Glucocorticoid Use or Assisted Reproduction Techniques.

Isolated 17,20-lyase deficiency (ILD) is a partial form of 17α-hydroxylase/17,20-lyase deficiency that typically presents with infertility and lack of pubertal development. Successful live births have been achieved using assisted reproductive techniques. We present a case of spontaneous pregnancy in an 18-year-old female with ILD without reproduction treatments or glucocorticoid use. She presented to our clinic with absence of pubarche and oligomenorrhea and had typical external genitalia and complete breast development. Follicular phase progesterone and estradiol were within reference values, and androgen levels were undetectable. Corticosterone was increased, and cortisol responded partially to the ACTH-stimulation test. This profile raised a suspicion for ILD, which was confirmed by the finding of the homozygous p.R347H variant in the CYP17A1 gene. Sex steroid replacement and glucocorticoid use during stress were prescribed. She returned 2 years later 20 weeks pregnant. Her gestation was uneventful, and a full-term healthy male was born. This phenomenon could be partially explained by sufficient estrogen synthesis via residual 17,20-lyase enzymatic activity. Intermittent estradiol use may have favored uterine development and fine-tuned the pituitary-gonadal axis rhythm. Normal progesterone levels may have permitted an adequate endometrial "implantation window" without glucocorticoid use. Finally, elevated corticosterone may have compensated for the partial cortisol deficiency.

Congenital Adrenal Hyperplasia with Combined 21-hydroxylase deficiency and 17α-hydroxylase/17,20-lyase deficiency: An undervirilized male.

21-hydroxylase deficiency stands as the most prevalent form of congenital adrenal hyperplasia, primarily resulting from mutations in the CYP21A2 gene. On the other hand, mutations within the CYP17A1 gene lead to 17α-hydroxylase/17,20-lyase enzyme deficiencies. The scarcity of 17-OH deficiency is noteworthy, accounting for less than 1% of all congenital adrenal hyperplasia cases. The male patient, born from a first-degree cousin marriage, exhibited several symptoms, including left undescended testis, micropenis, penile chord, left sensorineural hearing loss, and gynecomastia. He reported micropenis as a concern at the age of 13.5 years. His hormone profile revealed high levels of serum 17-hydroxyprogesterone, progesterone, and pregnenolone. In this case with a 46 XY karyotype, suspicions arose regarding Cytochrome P450 oxidoreductase deficiency due to ambiguous genitalia and an atypical hormone profile. Analysis unveiled two distinct homozygous and pathogenic variants in the CYP21A2 and CYP17A1 genes. Notably, mineralocorticoid precursors escalated, while cortisol and sex steroid precursors decreased during the high (250 mcg) dose ACTH stimulation test. The mutation c.1169C > G (p.Thr390Arg) in CYP17A1, which is the second documented case in literature, stands out due to its unique set of accompanying features. Mutations occurring in CYP21A2 and CYP17A1 result in complete or partial enzyme deficiencies, and the detection of homozygous mutations in two different enzyme systems within the steroidogenic pathway is noteworthy.

Congenital Adrenal Hyperplasia - A Comprehensive Review of Genetic Studies on 21-Hydroxylase Deficiency from India.

Congenital adrenal hyperplasia (CAH) comprises a heterogeneous group of autosomal recessive disorders impairing adrenal steroidogenesis. Most cases are caused by mutations in the CYP21A2 gene resulting in 21-hydroxylase (21-OH) deficiency (21-OHD). The genetics of 21-OH CAH is complexed by a highly homologous pseudogene CYP21A1P imposing several limitations in the molecular analysis. Therefore, genetic testing is still not a part of routine CAH diagnosis and is mainly dependent on 17-hydroxy progesterone (OHP) measurements. There are very few reports of CYP21A2 gene analysis from India and there is no comprehensive review available on genetic testing and the spectrum of CYP21A2 mutations from the country. This review focuses on the molecular aspects of 21-OHD and the genetic studies on CYP21A2 gene reported from India. The results of these studies insist the compelling need for large-scale CYP21A2 genetic testing and newborn screening (NBS) in India. With a high disease prevalence and consanguinity rates, robust and cost-effective genetic testing for 21-OH CAH would enable an accurate diagnosis in routine clinical practice. Whereas establishing affordable genotyping assays even in secondary care or resource-poor settings of the country can identify 90% of the mutations that are pseudogene derived, initiatives on reference laboratories for CAH across the nation with comprehensive genetic testing facilities will be beneficial in those requiring extended analysis of CYP21A2 gene. Further to this, incorporating genetic testing in NBS and carrier screening programmes will enable early diagnosis, better risk assessment and community-based management.

Divergent Gender Identity in a Phenotypic Male with 46XX Karyotype Caused by a Mutation in CYP21A2 Gene with Congenital Adrenal Hyperplasia.

A male patient in his late twenties presented with ambiguous genitalia to our tertiary specialist unit with complaints of short stature and inadequate copulation. There was no history of consanguinity, and a physical examination raised concerns about possible disorders of sexual development (DSD). Karyotyping and fluorescence in situ hybridization results were consistent with the presence of two X chromosomes, revealing the patient to be a genotypic female. Sanger sequencing showed a heterozygous pathogenic mutation in the CYP21A2 gene known to be associated with 21-hydroxylase deficiency, thus confirming the diagnosis of congenital adrenal hyperplasia (CAH), Prader stage V. DSD with CAH is distressing for the patient and their families, and the management needs a multidimensional approach involving diverse medical, genetic, and psychological considerations. Cytogenetic and molecular genetic studies play an essential role in diagnosis and decision-making and should be made affordable in developing countries for better patient care.

CYP17A1 Pathogenic Variants in 26 Chinese Patients with 17α-Hydroxylase Deficiency by Targeted Long-read Sequencing.

BACKGROUND: 17α-hydroxylase/17,20-lyase deficiency (17-OHD) is a rare subtype of congenital adrenal hyperplasia (CAH) caused by homozygous or compound heterozygous pathogenic variants in the CYP17A1 gene. PURPOSE: This study aimed to identify and characterize pathogenic variants in individuals with 17-OHD, and to classify and validate the pathogenicity of novel variants. METHODS: Variants were identified via targeted long-read sequencing (TLRS) of the entire CYP17A1 gene in enrolled 17-OHD patients. The American College of Medical Genetics and Genomics guidelines were employed to assess the pathogenicity of novel variants. A minigene splicing assay was utilized to determine the impact of variants on RNA splicing. RESULTS: This study encompassed 26 patients with 17-OHD, detecting two trans pathogenic variants per patient using the TLRS method. A total of 20 pathogenic variants in the CYP17A1 were identified, with variant c.985_987delinsAA being the most frequent (28/52 alleles), followed by variant c.1459_1467del (4/52 alleles). Five novel variants including c.280T>C, c.470T>A, c.636_637del, c.866A>G, and c.1095del, were classified as pathogenic/likely pathogenic ones according to ACMG criteria. The minigene assay revealed c.866A>G in exon 5 causes a frameshift due to a 104 base pair deletion, while c.470T>A generates two transcripts, with vast majority spliced like the wild-type, and a small fraction lack 35 base pairs in the 5' flank of exon 3. CONCLUSION: The TLRS can determine the cis/trans orientation of two distant variants. Five novel pathogenic variants were reported, broadening the spectrum of CYP17A1 pathogenic variant. The variant c.866A>G, located deep in exon, affects gene function through mechanisms of aberrant splicing.

Rapid detection of common variants and deletions of CYP21A2 using MALDI-TOF MS.

Newborn screening (NBS) for congenital adrenal hyperplasia (CAH) based on hormonal testing is successfully implemented in many countries. However, this method cannot detect non-classic CAH and has high false positive rates. We have developed a novel MALDI-TOF MS assay that can identify common variants and deletions of CYP21A2 in the Chinese population. Thirty-seven clinical patients with CAH confirmed by Sanger sequencing and MLPA analysis were detected by MALDI-TOF MS assay. Two CYP21A2 variants were detected in 30 patients and one CYP21A2 variant was detected in 7 patients. The MALDI-TOF MS assay detected 67 mutant alleles in 37 patients with a detection rate of 90.5%. Sanger sequencing revealed that three variants in seven patients were not included in the designed panel. Eleven distinct CYP21A2 variants were identified, including five missense variants, two nonsense variants, two large gene deletions, one splice variant, and one frameshift variant. The most frequent variant was c.293-13C > G (37.84%), followed by c.518T > A (21.62%) and exon 1-7 deletion (17.57%). The high-throughput MALDI-TOF MS assay that can simultaneously detect common variants and deletions of CYP21A2. This assay can be used for population-based genetic screening and rapid detection of suspected patients, and is expected to be a valuable complement to biochemical-based testing for the detection of CAH.

Current Advances in the Management of Congenital Adrenal Hyperplasia.

Congenital adrenal hyperplasia (CAH) is an autosomal recessive genetic condition caused by various enzyme deficiencies that result in disruptions of pathways of adrenal steroidogenesis. 21-hydroxylase deficiency is the most common form of CAH and has a variable phenotype which ranges a spectrum, from the most severe salt-wasting type to the simple-virilizing type and the least severe nonclassical form. Patients with CAH are at risk for various comorbidities due to the underlying adrenal hormone production imbalance as well as the treatment of the condition, which typically includes supraphysiologic glucocorticoid dosing. Children and adults require frequent monitoring and careful medication dosing adjustment. However, there are multiple novel therapies on the horizon that offer promise to patients with CAH in optimizing their treatment regimens and reducing the risk of comorbidities.

Genito-urinary Reconstruction in Female Children With Congenital Adrenal Hyperplasia: Favorable Surgical Outcomes can be Achieved by Contemporary Techniques and a Dedicated Multidisciplinary Management.

INTRODUCTION: Congenital adrenal hyperplasia (CAH) is the most common cause of genital atypia in females. A dedicated multidisciplinary team (MDT) should be included for an optimal management. Here, we aimed to review our surgical experience and to assess long-term urinary, gynecological and endocrine outcomes after primary genitoplasty in this specific cohort. METHODS: Patients born with CAH and who underwent feminizing genitoplasty in our institution were retrospectively identified (2001-2021). We analyzed patients' characteristics, intraoperative details, and postoperative urinary, gynecological, and endocrine outcomes. RESULTS: Forty patients were included and followed-up for a median (IQR) time of 7 (1-19) years. Thirty-eight (95%) had 21-hydroxylase deficiency. After multidisciplinary decision and written consent from patient and/or family, a single-stage reconstructive surgery was performed at a median age of 10 (3-165) months. Median length of hospital stay was 5 (1-7) days. Procedures were: PUM (N = 35 (87.5%)), TUM (N = 3 (7.5%)), urogenital mobilization was unnecessary in 2 (5%). Reduction clitoroplasty was done in 33 (82.5%) patients. Only 3 (7.5%) experienced significant Clavien-Dindo complications requiring additional surgery during the follow-up period. Recurrent urinary tract infections (UTI) occurred in 6 (15%), one required ureteric reimplantation for symptomatic high-grade vesicoureteric reflux. All patients over 3 years were toilet-trained without incontinence. Severe vaginal stenosis occurred in 1 (2.5%) patient. In patients who achieved puberty, 6/9 had vaginal calibration at a median age of 17.3 (16-21) years without detected stenosis. One (2.5%) had major hypertrophy of the right labia minora requiring labiaplasty. Nine (22.5%) reached puberty. Two (5%) patients developed acne/hirsutism. Short stature was noted in 11 (27.5%) and obesity in 18 (45%). CONCLUSION: Based on our contemporary series, genitourinary reconstructive surgery for female patients born with CAH is technically feasible and safe with a low complication rate. A regular follow-up with a MDT to assess long-term complications is necessary, and it is vital to inform patients and families about the different management options with all the risks and benefits of surgery. TYPE OF THE STUDY: original research, clinical research. LEVEL OF EVIDENCE: Level 3 retrospective study.

Abiraterone in Classic Congenital Adrenal Hyperplasia: Results of Medical Therapy Before Adrenalectomy.

We present the case of a 20-year-old woman with classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency, with uncontrolled hyperandrogenemia despite supraphysiological glucocorticoid therapy. We used abiraterone acetate, an inhibitor of the 17-hydroxylase/17,20-lyase enzyme, to suppress adrenal androgen synthesis and allow physiological glucocorticoid and mineralocorticoid therapy, as a proof-of-concept, before proceeding to bilateral adrenalectomy. We report the patient's clinical course, the changes in adrenal steroids, and the immunohistochemistry of the adrenals.

Successful live birth in women with partial 17α-hydroxylase deficiency: report of two cases.

RESEARCH QUESTION: Can women with partial 17α-hydroxylase deficiency (17-OHD) conceive naturally with adequate hormonal control and endometrial preparation? DESIGN: This report presents two cases of women with partial 17-OHD who achieved successful pregnancies. The first case involved a 27-year-old Chinese woman with recurrent cysts and infertility, and the second case involved a 32-year-old Chinese woman with a complex disorder requiring IVF. Both cases were treated with oral prednisone to control hormone concentrations and underwent endometrial preparation. RESULTS: In the first case, the patient resumed spontaneous ovulation, conceived naturally, and gave birth to a healthy baby. In the second case, after cryopreserving embryos due to a thin endometrium, the patient underwent frozen embryo transfer and achieved a singleton pregnancy. CONCLUSION: This study suggests that women with partial 17-OHD can conceive naturally with appropriate hormonal management and endometrial preparation. These findings provide valuable insights into the reproductive potential of women with this disorder, and highlight the importance of further research in this area.

Severe Carpal Tunnel Syndrome in a Pediatric Patient With a History of Congenital Adrenal Hyperplasia.

The patient is a 17-year-old right-hand-dominant girl with a history of virilizing congenital adrenal hyperplasia (CAH) secondary to 21-hydroxylase enzyme deficiency. Her CAH had been managed with supplemental exogenous steroids, but unfortunately, she had been noncompliant for many years. She subsequently presented with severe progressive numbness and tingling in the bilateral upper extremities that were refractory to conservative management. Electromyography/nerve conduction studies confirmed bilateral carpal tunnel syndrome (CTS) with the right being more severe than the left, and she underwent uncomplicated carpal tunnel releases that relieved her symptoms immediately and completely. Carpal tunnel syndrome secondary to CAH may be associated with the effects of elevated sex hormones within the CTS, leading to inflammation and median nerve entrapment. Moreover, hyperandrogenism is associated with elevated acute phase reactants and inflammatory cytokines, contributing to progressive median neuropathy. To the author's knowledge, there have been no reported cases of severe pediatric CTS with associated hyperandrogenism from CAH.

Multicenter Analysis of Cardiometabolic-Related Diagnoses in Youth with Congenital Adrenal Hyperplasia: a PEDSnet study.

CONTEXT: Small cohorts of youth with congenital adrenal hyperplasia (CAH) demonstrate increased risk of obesity and poor cardiometabolic health. OBJECTIVE: To determine the odds of cardiometabolic-related diagnoses in youth with CAH compared to matched controls in a cross-sectional analysis in a large, multisite database (PEDSnet). DESIGN: Electronic health record data (2009-2019) were used to determine odds of cardiometabolic-related outcomes based on diagnosis, anthropometric and laboratory data using logistic regression among youth with CAH vs. controls. SETTING: Six PEDSnet sites. PATIENTS OR OTHER PARTICIPANTS: Youth with CAH and >1 outpatient visit in PEDSnet (n=1,647) were propensity-score matched on 8 variables to controls (n=6,588). A subset of youth with classic CAH (n=547, with glucocorticoid and mineralocorticoid prescriptions) were matched to controls (n=2,188). INTERVENTION(S): N/A. MAIN OUTCOME MEASURE(S): Odds of having cardiometabolic-related diagnoses among youth over 2 years with CAH compared to matched controls. RESULTS: Outcomes were calculated for all individuals with CAH (median age at last visit 12.9 years [7.3, 17.6]) and a subset with classic CAH (median age at last visit 11.6 years [4.7, 17.5]) compared to their matched controls. All patients with CAH had higher odds of overweight/obesity (odds ratio [95% confidence interval] 3.63 [3.24,4.07]), hypertension (3.07 [2.60,3.64]), dysglycemia (1.95 [1.35,2.82], dyslipidemia (2.28 [1.79,2.91]) and liver dysfunction (2.30 [1.91,2.76]) compared to matched controls. Patients with classic CAH had higher odds of overweight/obesity (3.21 [2.61,3.93]), hypertension (8.22 [6.71,10.08]), and liver dysfunction (2.11 [1.55,2.89]) compared to matched controls. CONCLUSIONS: Overall, youth with CAH are at increased risk of diagnoses related to worse cardiometabolic health.

A comparison of obstetric and neonatal outcomes in polycystic ovary syndrome and congenital adrenal hyperplasia: a retrospective analysis of a population database.

OBJECTIVE: To investigate potential differences in pregnancy, delivery, and neonatal outcomes between 2 hyperandrogenic conditions in reproductive-aged women: polycystic ovary syndrome (PCOS) and congenital adrenal hyperplasia (CAH). DESIGN: Retrospective population-based study with data from the Health Care Cost and Utilization Project-Nationwide Inpatient Sample Database from 2004-2014. SETTING: Not applicable. PATIENT(S): A total of 14,881 women with PCOS and 298 women with CAH. INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Gestational diabetes mellitus, placenta previa, pregnancy-induced hypertension (HTN), gestational HTN, preeclampsia, eclampsia, preeclampsia and eclampsia superimposed on HTN, preterm birth, preterm premature rupture of membrane, abruptio placenta, chorioamnionitis, mode of delivery, maternal infection, hysterectomy, blood transfusion, venous thromboembolism (deep vein thrombosis and pulmonary embolism during pregnancy, intrapartum, or postpartum), maternal death, chorioamnionitis, septicemia during labor, postpartum endometritis, septic pelvic, peritonitis, small for gestational age, congenital anomalies, and intrauterine fetal demise. RESULT(S): After adjusting for potential confounders, we found that women with PCOS were at increased risk of developing pregnancy-induced HTN (adjusted odds ratio [OR] = 1.76; 95% confidence interval [CI]: 1.12-2.77) and gestational diabetes (adjusted OR = 1.68; 95% CI: 1.12-2.52) when compared with women with CAH. Contrary women with CAH were at increased risk for delivery via cesarean section (adjusted OR = 0.59; 95% CI: 0.44-0.80) and small for gestational age neonates (adjusted OR = 0.32; 95% CI: 0.20-0.52). CONCLUSION(S): To our knowledge, this study is the first to directly compare obstetric and neonatal outcomes between patients with PCOS and CAH. Despite the similar phenotypes and some common hormonal and biochemical profiles, such as insulin resistance, hyperinsulinemia, and hyperandrogenism, our results suggest the existence of additional metabolic pathways implicated in the pathogenesis of pregnancy complications.

CAHQL: A patient reported outcome instrument to assess health-related quality of life in congenital adrenal hyperplasia.

CONTEXT: Measuring health-related quality of life (HRQoL) is a crucial aspect of evaluating health care outcomes. Patients with congenital adrenal hyperplasia (CAH) often self-report deficiencies in HRQoL. OBJECTIVE: The aim of our study was to develop a disease-specific patient reported outcome (PRO) instrument to evaluate the HRQoL of patients >16 years old with classic congenital adrenal hyperplasia (CAH). DESIGN, SETTING AND OUTCOMES: Following the FDA guidelines for developing PRO instruments, we developed a conceptual framework for the instrument. A preliminary instrument was created after interviewing a representative sample of 12 patients with CAH between 16 to 68 years old and 3 parents, and obtaining expert feedback from 4 endocrinologists. The instrument was edited after cognitive interviews with 6 patients. Internal consistency of the instrument was evaluated using Cronbach's alpha. Validity was assessed by comparing the scores of our instrument with scores from widely used validated instruments for HRQoL and PRO not specific to CAH. RESULTS: Sixty-nine patients 16 to 75 years old participated in validating our preliminary instrument. The final questionnaire consists of 44 questions within 7 domains: General Health, Adrenal Insufficiency, Glucocorticoid Excess, Physical Functioning, Mental Health and Cognition, Social Functioning, and Sexual Functioning, with acceptable internal consistency (Chronbach's alpha≥0.6) and validity (r = -0.350 to 0.866). CONCLUSION: CAHQL is the first validated PRO instrument to capture disease specific HRQoL outcomes in CAH. In addition to its anticipated use in the clinical setting, the instrument could be used to assess the efficacy of novel treatments in development.

Case report: Development of central precocious puberty in a girl with late-diagnosed simple virilizing congenital adrenal hyperplasia complicated with Williams syndrome.

Congenital adrenal hyperplasia (CAH) and Williams Syndrome (WS; MIM # 194050) are distinct genetic conditions characterized by unique clinical features. 21-Hydroxylase deficiency (21-OHD; MIM #201910), the most common form of CAH, arises from mutations in the CYP21A2 gene, resulting in virilization of the external genitalia in affected females, early puberty in males, and short stature. Williams syndrome, caused by a microdeletion of 7q11.23, presents with distinctive facial features, intellectual disability, unique personality traits, early puberty, and short stature. This case report describe the clinical features of a 4-year-old girl referred due to progressive virilization and developmental delay. Genetic analysis confirmed concurrent CAH and WS, identifying a novel mutation in the CYP21A2 gene (c.1442T>C). Following corticosteroid therapy initiation, the patient developed central precocious puberty. This case report delves into the pubertal change patterns in a patient affected by overlapping genetic conditions, providing valuable insights in to the intricate clinical manifestation and management of these rare complex disorders.

Can incorporating molecular testing improve the accuracy of newborn screening for congenital adrenal hyperplasia?

BACKGROUND: Single-tier newborn screening (NBS) for CAH using 17-hydroxyprogesterone (17OHP) measured by fluoroimmunoassay (FIA) in samples collected at 24-48 hours produces a high false-positive rate (FPR). 2nd tier steroid testing can reduce the FPR and has been widely implemented. We investigated the accuracy of an alternative multi-tier CAH NBS protocol that incorporates molecular testing of the CYP21A2 gene and reduces the 1st tier 17OHP cutoff to minimize missed cases. METHODS: Created a Minnesota-specific CYP21A2 pathogenic variants panel; develop a rapid, high-throughput multiplex, allele-specific-primer-extension assay; perform 1-year retrospective analysis of Minnesota NBS results comparing metrics between a conventional steroid-based two-tier protocol and a molecular-based multi-tier NBS protocol, applied post-hoc. RESULTS: CYP21A2 gene sequencing of 103 Minnesota families resulted in a Minnesota-specific panel of 21 pathogenic variants. Centers for Disease Control and Prevention (CDC) created a molecular assay with 100% accuracy and reproducibility. Two-tier steroid-based screening of 68,659 live births during 2015 resulted in 2 false negatives (FNs), 91 FPs, and 1 true positive (TP). A three-tier protocol with a lower 1st-tier steroid cutoff, 2nd-tier 21-variant CYP21A2 panel and 3rd-tier CYP21A2 sequencing would have resulted in 0 FNs, 52 FPs and 3 TPs. CONCLUSIONS: Incorporation of molecular testing could improve the accuracy of CAH NBS, although some distinct challenges of molecular testing may need to be considered before implementation by NBS programs.

Challenging Molecular Diagnosis of Congenital Adrenal Hyperplasia (CAH) Due to 21-Hydroxylase Deficiency: Case Series and Novel Variants of CYP21A2 Gene.

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive genetic defects in cortisol synthesis and shows elevated ACTH concentrations, which in turn has downstream effects. The most common variant of CAH, 21-hydroxylase deficiency (21OHD), is the result of pathogenic variants in the CYP21A2 gene and is one of the most common monogenic disorders. However, the genetics of 21OHD is complex and challenging. The CYP21A2 gene is located in the RCCX copy number variation (CNV), a complex, multiallelic, and tandem CNV in the major histocompatibility complex (MHC) class III region on chromosome 6 (band 6p21.3). Here, CYP21A2 and its pseudogene CYP21A1P are located 30 kb apart and share a high nucleotide homology of approximately 98% and 96% in exons and introns, respectively. This high-sequence homology facilitates large structural rearrangements, copy number changes, and gene conversion through intergenic recombination. There is a good genotype-phenotype correlation in 21OHD, and genotyping can be performed to confirm the clinical diagnosis, predict long-term outcomes, and determine genetic counseling. Thus, genotyping in CAH is clinically relevant but the interpretations can be challenging for non-initiated clinicians. Here, there are some concrete examples of how molecular diagnosis can sometimes require the use of multiple molecular strategies.

Novel STAR Gene Variant of Congenital Lipoid Adrenal Hyperplasia With Testicular Adrenal Rests.

A mutation in the steroidogenic acute regulatory protein (STAR) gene, which encodes a protein that plays a crucial role in steroid hormone synthesis, causes a severe form of congenital adrenal hyperplasia (CAH) known as lipoid CAH (LCAH). LCAH presents with primary adrenal insufficiency (PAI) as well as atypical genitalia. Individuals with LCAH require adrenal steroid hormone supplements for survival. Masculinization in males with STAR deficiency varies from incomplete to normal virilization. Radiological examinations reveal enlarged and lipid-laden adrenals. A 10-year-old boy born of second-degree consanguinity presented with weight gain and hyperpigmentation for 1 year. He was diagnosed with PAI at age 7 months and treated with hydrocortisone and fludrocortisone. Dynamic adrenal gland testing revealed undetectable hormone reserves. Imaging detected hypoplastic adrenals and a small testis with testicular adrenal rests (TART). Genetic analysis indicated a novel homozygous pathogenic variant of STAR in exon 7, c.814C > G(pArg272Gly) associated with LCAH (OMIM No. 201710). Testing revealed that asymptomatic family members and relatives were heterozygotes for the variant. The patient was diagnosed with nonclassic LCAH with hypoplastic adrenals and TART. Adequate hormone supplementation resulted in TART regression. This genetic variation is reported for the first time.

Revealing a New Homozygous Variant in CYP17A1 c.908G>A (p. Gly303Asp) by Genotyping a Chinese Patient with 46, XY 17a-Hydroxylase/17,20-Lyase Deficiency and Adrenal Space-Occupying Lesion.

BACKGROUND: 17α-hydroxylase/17,20-lyase deficiency (17OHD) is an autosomal recessive genetic disorder caused by a mutation of the cytochrome P450, family 17, subfamily A, polypeptide 1 (CYP17A1). This study reports the case of a 22-year-old Chinese patient (46, XY) with 17OHD and a unilateral adrenal space-occupying lesion. METHODS: The patient underwent serological, radiographic, genetic, and molecular analyses including whole-genome exome sequencing through high-throughput sequencing (HTS) technology to analyze the genetic conditions of both the patient and her parents. Additionally, chromosomal karyotype analysis was performed. The impact of the novel mutation on protein conformation was investigated by examining the three-dimensional structure of human CYP17A1 using the SWISS-MODEL website tool (PDB code 3RUK). RESULTS: The patient had a chromosomal karyotype 46, XY, and presented with hypertension, hypokalemia, and male pseudohermaphroditism. Furthermore, decreased levels of testosterone, dehydroepiandrosterone sulfate, and estradiol, along with increased levels of progesterone, luteinizing hormone, and follicle-stimulating hormone (FSH), were observed. DNA sequencing revealed a homozygous mutation (c.908G>A, p.G303A) in the fifth exon of the CYP17A1. Both parents carried a heterozygous c.908G>A mutation in the same exon, confirming the inheritance of the patient's exonic mutation. CONCLUSION: For the first time, this study reports a novel homozygous mutation (c.908G>A in the fifth exon) in CYP17A1. Modeling analysis of CYP17A1 suggested that the substitution of glycine with aspartic acid at position 303 induces alterations in the number, structure, and electrostatic potential of the protein's local binding sites. The p.G303A mutation may possess pathogenic properties. Our study expands the mutation spectrum of CYP17A1.