Marwa Elsharkawy

Background: Congenital adrenal hyperplasia (CAH) is a monogenic disorder caused by genetic diversity in the CYP21A2 gene, with 21-hydroxylase deficiency (21-OHD) as the most common type. Early sex assignment and early diagnosis of different genetic variations with a proper technique are important to reduce mortality and morbidity. Proper early sex identification reduces emotional, social, and psychological stress.Aim: Detection of a spectrum of aberrations in the CYP21A2 gene, including copy number variations, gene conversion, chimeric genes, and point variations.Methods: The CYP21A2 gene was screened using MLPA assay in 112 unrelated Egyptian children with 21-OHD CAH (33 males and 79 females).Results: In the studied group, 79.5% were diagnosed within the first month of life. 46.8% of the genetic females were misdiagnosed as males. Among the copy number variation results, large deletions in 15.4% and three types of chimeric genes in 9% (CH-1, CH-7, and CAH-X CH-1) were detected. Regarding gene dosage, one copy of CYP21A2 was found in 5 cases (4.5%), three copies were detected in 7 cases (6.3%), and one case (0.9%) showed four copies. Eight common genetic variants were identified, I2G, large deletions, large gene conversion (LGC), I172N, F306 + T, -113 SNP, 8bp Del, and exon 6 cluster (V237E and M239K) with an allelic frequency of 32.62%, 15.45%, 7.30%, 3.00%, 2.58%, 2.15%, 0.86%, and 0.86%, respectively.Conclusion: High prevalence of copy number variations highlights the added value of using MLPA in routine laboratory diagnosis of CAH patients.

Background: Measurement of multiple steroids, 17 hydroxyprogesterone, 11 deoxycortisol, and 21 deoxycortisol, is required to discriminate between congenital adrenal hyperplasia due to 21 hydroxylase deficiency and that due to 11 beta hydroxylase deficiency. This work aims at the selection of the more appropriate, cost-effective method among either mass spectrometry or radioimmunoassay for the quantitation of the previous steroids. In this study, blood samples were collected from 31 patients that were newly diagnosed with congenital adrenal hyperplasia; 17 hydroxyprogesterone and 21 deoxycortisol were assayed using tandem mass spectrometry. Eleven deoxycortisol was assayed using 2 methods: radioimmunoassay and tandem mass spectrometry. Results: Measuring 11 deoxycortisol using tandem mass spectrometry could significantly discriminate patients with 11 beta hydroxylase deficiency from those with 21 hydroxylase deficiency (p = 0.002), whereas radioimmunoassay failed (p = 0.095). Moreover, the former was highly predictive of 11 beta hydroxylase deficiency at a cutoff ≥ 11 ng/ml with 100% sensitivity and 92.3% specificity. Simultaneous measurement of 21 deoxycortisol and 11 deoxycortisol and their enrollment in an equation yielded an overall predictive accuracy 96.8% for diagnosis of CAH due to both enzymatic deficiencies. Conclusions: Measurement of 11 deoxycortisol using mass spectrometric approach is mandated as a part of work up to differentiate types of congenital adrenal hyperplasia.

Objectives The prevalence of CAH in Egypt is reported to be ten times more than that of the worldwide prevalence. The study aimed at genetic screening of children diagnosed with 21-alpha hydroxylase deficiency congenital adrenal hyperplasia (21OHD-CAH). In addition, the study offers a rapid and easy guide for clinical reporting of common mutations for endocrinologists. Methods A cohort of 174 unrelated Egyptian children with 21OHD-CAH were screened for 11 common CYP21A2 gene mutations using a strip hybridization assay, and then, bioinformatics analysis was done to report the pathogenicity of the common mutations for clinical classification. Results The most common mutations were I2 splice and p.Q318X. Deletions/conversions comprised 45.9% of the cohort, whereas 7.4% of the cases were negative for all mutations. The least positively detected point mutations were p.P453S, cluster E6, p.R483P, and p.L307FS, which were detected in fewer than 5% of cases. Conclusion Strip hybridization assay is a rapid screening tool for the diagnosis of CAH. The authors hypothesized an easy and rapid scheme for clinical interpretation of the strip results to gain the highest value of the strip in diagnosis.

Summary: Background: Early childhood obesity is a public health problem worldwide. It affects different aspects of physical and mental child's health. Identifying the etiologies, especially treatable and preventable causes, can direct health professionals toward proper management. Analysis of serum leptin levels and leptin gene mutations is a rapid and easy step toward the diagnosis of congenital leptin deficiency that is considered an important cause in early childhood obesity.Objectives: The aim of this study was to diagnose monogenic leptin deficiency in Egyptian children presenting with early onset obesity (EOO).Methods: The current cross‐sectional study included 80 children who developed obesity during the first year of life with BMI > 2 SD (for age and sex). The studied population was subjected to history taking, auxological assessment, serum leptin assay, and leptin gene sequencing.Results: Ten cases had leptin deficiency (12.5%), while 18 cases showed elevated leptin levels (22.5%). Leptin gene variants in the coding region were identified in 30% of the leptin‐deficient group: two novel homozygous disease‐causing variants (c.104 T > G and c.34 delC) and another previously reported homozygous pathogenic variant (c.313C > T).Conclusion: Leptin deficiency is considered a significant cause of monogenic obesity in Egyptian children with early‐onset obesity as the diagnosis of these patients would be a perfect target for recombinant leptin therapy.

Objectives: Permanent neonatal diabetes (PNDM) is caused by mutations in the genes responsible for the synthesis of different proteins that are important for the normal behavior of beta cells in the pancreas. Mutations in the insulin gene (INS) are considered as one of the causes of diabetes in neonates. This study aimed to investigate the genetic variations in the INS gene in a group of Egyptian infants diagnosed with PNDM. Methods: We screened exons 2 and 3 with intronic boundaries of the INS gene by direct gene sequencing in 30 PNDM patients and 20 healthy controls. A detailed clinical phenotyping of the patients was carried out to specify the diabetes features in those found to carry an INS variant. Results: We identified five variants (four SNPs and one synonymous variant), c(0).187 + 11T > C, c.-17-6T > A, c.*22A > C, c.*9C > T, and c.36G > A (p.A12A), with allelic frequencies of 96.7%, 80%, 75%, 5%, and 1.7%, respectively. All showed no statistically significance difference compared with the controls, with the exception of c.*22A > C. Conclusion: Genetic screening for the INS gene did not reveal an evident role in the diagnosis of PNDM.

Steroid 21-hydroxylase deficiency (21-OHD) is the common type of congenital adrenal hyperplasia (CAH) caused by defects in the CYP21A2 gene, as an autosomal recessive disease, genetic analysis has a prominent role in its diagnosis. Our objectives were to determine the prevalence of common mutations in a group of Egyptian patients with 21-OHD and their families using rapid methods, and also to detect the rate of deletion, duplication and conversions in CYP21A2 gene. Rapid detection methods were used: allele-specific PCR for c.293-13A>G (g.659A>G), c.518T>A (p.I172N) variants and c.332_339del (8-bp deletion in exon 3), and real-time, quantitative PCR assay was used to detect deletion in the CYP21A2 gene. 29 Egyptian patients, 38 family members, and 20 healthy controls were all included in the study. The frequency of c.293-13A>G splice mutation was reported in 96.6 % cases, G allele had 2.5-folds higher risk to develop CAH than other alleles. The c.518T>A mutation was reported in 69 % cases, children carrying the mutant allele were 2.1 times more risk. The most frequent combined mutations detected were c.293-13A/C>G/c.518T>A in 58.6 % cases. The genetic analysis of the splice site mutation c.293-13A>G and c.518T>A variant can be used as good biomarkers for early detection of cases and carriers in 21-OHD CAH Egyptian children, since the methods used have rapid turnaround time.