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1.
Hormones (Athens) ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38526829

RESUMEN

PURPOSE: Leydig cell hypoplasia (LCH) type II is a rare disease with only a few cases reported. Patients presented with hypospadias, micropenis, undescended testes, or infertility. In this study, we report a new patient with compound heterozygous variants in the LHCGR gene and LCH type II phenotype. METHODS: Whole exome sequencing (WES) was performed followed by Sanger sequencing to confirm the detected variants in the patient and his parents. RESULTS: A novel missense variant (p.Phe444Cys) was identified in a highly conserved site and is verified to be in trans with the signal peptide's 33-bases insertion variant. CONCLUSION: Our research provides a more comprehensive clinical and genetic spectrum of Leydig cell hypoplasia type II. It highlighted the importance of WES in the diagnosis of this uncommon genetic disorder as well as the expansion of the genotype of LCH type II.

2.
J Appl Toxicol ; 43(11): 1645-1666, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37340691

RESUMEN

The Japanese medaka (Oryzias latipes) extended one-generation reproduction test (MEOGRT) (Test Guideline 890.2200) is a Tier 2 test within the Endocrine Disruptor Screening Program of the US Environmental Protection Agency (US EPA). A modified MEOGRT was used to evaluate multigenerational effects of 2-ethylhexyl 4-hydroxybenzoate (2-EHHB) under flow-through conditions starting with adults (parent generation, F0) through a 3-week reproductive phase of the second generation (F2). Fish were exposed to one of five 2-EHHB test concentrations or a dechlorinated tap water control. Fecundity was affected at the lowest exposure (5.32 µg/L) and greater sensitivity occurred in the F1 and F2 generations. Percent fertility was also diminished from no effect level observed in the F0 generation to 101 and 48.8 µg/L in the F1 and F2 generations, respectively. Growth indices were decreased for F0 adult females and F1 subadults and adults at 48.8 µg/L 2-EHHB. Histopathologic examination of gonads, liver, kidney, and thyroid yielded possible delayed reproductive tract development in F1 subadult males, masculinization of the renal phenotype in F1 adult females (renal tubular eosinophilia) and reduced hepatic energy storage (liver glycogen vacuoles) in F1 (11.3 and 48.8 µg/L) and F2 (48.8 and 101 µg/L) males and females, respectively. Endocrine-related findings included a decrease in anal fin papillae in F2 adult males at 101 µg/L. Results of this study demonstrate effects on growth, development, and reproduction that may be mediated by endocrine (weak estrogenic) and nonendocrine mechanisms. Duration of the MEOGRT should not be routinely extended beyond the OCSPP 890 guideline study design.

3.
Regul Toxicol Pharmacol ; 134: 105241, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35940297

RESUMEN

2-Ethylhexyl 4-hydroxybenzoate (2-EHHB), 4-tert-octylphenol (4-OP), 4-nonylphenol-branched (4-NP), benzyl butyl phthalate (BBP) and dibutyl phthalate (DBP) were evaluated using a 21-day Amphibian Metamorphosis Assay (AMA). Xenopus laevis larvae were exposed nominally to each chemical at 3.6, 10.9, 33.0, and 100 µg/L, except 4-NP concentrations were 1.8, 5.5, 16.5 and 50 µg/L. Endpoints included mortality, developmental stage, hind limb length (HLL), snout-vent length (SVL), body weight (BW), and thyroid histopathology. BBP and 4-OP accelerated development compared to controls at the mean measured concentration of 3.5 and 39.8 µg/L, respectively. An increase in developmental stage frequency distribution was observed for 4-OP at 39.8 and 103 µg/L, BBP at all concentrations and DBP at 143 µg/L. Normalized HLL was increased on study day (SD) 21 for all tested substances except 4-NP. Histopathology revealed accelerated development and mild thyroid follicular cell hypertrophy at all BBP concentrations, but moderate severity at 105 µg/L. Increased BW occurred for all chemicals except 4-OP. Increased SVL was observed for 4-NP, BBP and DBP on SD 21. There was insufficient evidence that 4-NP and 2-EHHB affected the hypothalamic-pituitary thyroid axis, however, BBP, DBP and 4-OP showed potential effects on amphibian metamorphosis and thyroid activity, albeit through different lines of evidence.


Asunto(s)
Disruptores Endocrinos , Glándula Tiroides , Animales , Bioensayo , Disruptores Endocrinos/toxicidad , Larva , Metamorfosis Biológica , Xenopus laevis
4.
Sex Dev ; 16(4): 261-265, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35045414

RESUMEN

INTRODUCTION: Disorders of gonadal development represent a clinically and genetically heterogeneous group of DSD, and the etiology in many cases remains unknown, indicating that our knowledge of factors controlling sex determination is still limited. METHODS: We describe a 46,XY DSD patient from Egypt. The patient was reared as female, born to consanguineous parents, and was referred to us at the age of 5 years because of ambiguous genitalia. On examination, the girl was microcephalic (head circumference -3 SD), but her height and weight were normal for her age and sex. RESULTS: Exome sequencing identified a homozygous variant in the hedgehog acyltransferase (HHAT) gene, which encodes an enzyme that is required for multimerization and signaling potency of the hedgehog secreted proteins. The variant is a novel homozygous missense change c.1329C>A (p.N443K), located within transmembrane domain 9, which segregated with the phenotype in the family. DISCUSSION/CONCLUSION: Our results expand the phenotypic spectrum associated with HHAT variants to include 46,XY gonadal dysgenesis and reinforce the role of exome sequencing in unraveling new genes that play a pivotal role in sexual development.


Asunto(s)
Disgenesia Gonadal 46 XY , Proteínas Hedgehog , Femenino , Humanos , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Disgenesia Gonadal 46 XY/diagnóstico , Mutación Missense/genética , Homocigoto , Fenotipo , Mutación , Aciltransferasas/genética
5.
Mol Genet Genomic Med ; 9(11): e1829, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34609792

RESUMEN

BACKGROUND: This study aimed to delineate the clinical phenotype of patients with 9p deletions, pinpoint the chromosomal breakpoints, and identify the critical region for trigonocephaly, which is a frequent finding in 9p terminal deletion. METHODS: We investigated a cohort of nine patients with chromosome 9p terminal deletions who all displayed developmental delay, intellectual disability, hypotonia, and dysmorphic features. Of them, eight had trigonocephaly, seven had brain anomalies, seven had autistic manifestations, seven had fair hair, and six had a congenital heart defect (CHD). RESULTS: Karyotyping revealed 9p terminal deletion in all patients, and patients 8 and 9 had additional duplication of other chromosomal segments. We used six bacterial artificial chromosome (BAC) clones that could identify the breakpoints at 17-20 Mb from the 9p terminus. Array CGH identified the precise extent of the deletion in six patients; the deleted regions ranged from 16 to 18.8 Mb in four patients, patient 8 had an 11.58 Mb deletion and patient 9 had a 2.3 Mb deletion. CONCLUSION: The gene deletion in the 9p24 region was insufficient to cause ambiguous genitalia because six of the nine patients had normal genitalia. We suggest that the critical region for trigonocephaly lies between 11,575 and 11,587 Mb from the chromosome 9p terminus. To the best of our knowledge, this is the minimal critical region reported for trigonocephaly in 9p deletion syndrome, and it warrants further delineation.


Asunto(s)
Deleción Cromosómica , Craneosinostosis , Cromosomas , Craneosinostosis/genética , Egipto , Humanos , Cariotipificación
6.
Mol Syndromol ; 12(2): 87-95, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34012377

RESUMEN

Mowat-Wilson syndrome (MWS) is a rare autosomal dominant syndrome characterized by dysmorphic features, mental retardation, and congenital heart disease (CHD). MWS results from microdeletions of chromosome 2q23 or de novo SNVs involving the ZEB2 gene. Here, we report on an Egyptian MWS patient diagnosed by chromosomal microarray (CMA). A 1-year-old male child was referred to the CHD clinic, National Research Centre, presenting with dysmorphic features and CHD. The patient was referred to the human cytogenetics department for cytogenetic analysis and for screening of subtelomere rearrangements and microdeletion loci, using MLPA, and all revealed normal results. CMA revealed an interstitial 2.27-Mb microdeletion in chromosome 2q, involving the entire ZEB2 gene and other genes. This study emphasizes the significance of CMA in the detection of microdeletions/microduplications and as a screening tool in cases presenting with CHD and extracardiac manifestations. MWS should be suspected in patients presenting with the characteristic facial dysmorphism, developmental delay, seizures, Hirschsprung disease, and congenital heart anomalies, especially those involving the pulmonary arteries or pulmonary valves. It is recommended to include the ZEB2 locus in the MLPA microdeletions probes.

7.
J Pediatr Genet ; 10(2): 131-138, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33996184

RESUMEN

Paternal microduplication of 11p14.3-p15.5 causes the clinical manifestations of Beckwith-Wiedemann syndrome (BWS), while microdeletion of 18q23-ter is clinically characterized by short stature, congenital malformations, and developmental delay. We describe a 15-month-old girl presenting with protruding tongue, dysmorphic facial features, moderate developmental delay, umbilical hernia, hypotonia, mild-to-moderate pulmonary hypertension, small patent ductus arteriosus, and mild ventricular septal hypertrophy. Brain magnetic resonance imaging showed mild atrophic changes. Chromosomal analysis revealed 46, XX, add(18)(q23). Fluorescence in situ hybridization using subtelomere 18q and whole chromosome painting 18 showed subtelomere deletion in 18q, and the add segment was not derived from chromosome 18. Microarray-based comparative genomic hybridization detected a 22 Mb duplication of chromosome 11p15.5p14.3 and a 3.7 Mb deletion of chromosome 18q23. The phenotype of the chromosomal rearrangements is probably resulted from a combination of dosage-sensitive genes. Our patient had clinical manifestations of both 18q deletion and BWS.

8.
Am J Med Genet A ; 185(6): 1666-1677, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33742552

RESUMEN

Disorders/differences of sex development (DSD) comprise a group of congenital disorders that affect the genitourinary tract and usually involve the endocrine and reproductive system. The aim of this work was to identify genetic variants responsible for disorders of human urogenital development in a cohort of Egyptian patients. This three-year study included 225 patients with various DSD forms, referred to the genetic DSD and endocrinology clinic, National Research Centre, Egypt. The patients underwent thorough clinical examination, hormonal and imaging studies, detailed cytogenetic and fluorescence in situ hybridization analysis, and molecular sequencing of genes known to commonly cause DSD including AR, SRD5A2, 17BHSD3, NR5A1, SRY, and WT1. Whole exome sequencing (WES) was carried out for 18 selected patients. The study revealed a high rate of sex chromosomal DSD (33%) with a wide array of cytogenetic abnormalities. Sanger sequencing identified pathogenic variants in 33.7% of 46,XY patients, while the detection rate of WES reached 66.7%. Our patients showed a different mutational profile compared with that reported in other populations with a predominance of heritable DSD causes. WES identified rare and novel pathogenic variants in NR5A1, WT1, HHAT, CYP19A1, AMH, AMHR2, and FANCA and in the X-linked genes ARX and KDM6A. In addition, digenic inheritance was observed in two of our patients and was suggested to be a cause of the phenotypic variability observed in DSD.


Asunto(s)
Trastorno del Desarrollo Sexual 46,XY/genética , Predisposición Genética a la Enfermedad , Genómica , Desarrollo Sexual/genética , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/genética , Aciltransferasas/genética , Adolescente , Adulto , Aromatasa/genética , Niño , Preescolar , Estudios de Cohortes , Trastorno del Desarrollo Sexual 46,XY/fisiopatología , Egipto/epidemiología , Proteína del Grupo de Complementación A de la Anemia de Fanconi/genética , Femenino , Histona Demetilasas/genética , Proteínas de Homeodominio/genética , Humanos , Hibridación Fluorescente in Situ , Lactante , Masculino , Proteínas de la Membrana/genética , Mutación/genética , Fenotipo , Receptores Androgénicos/genética , Receptores de Péptidos/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Factores de Transcripción SOXB1/genética , Desarrollo Sexual/fisiología , Factor Esteroidogénico 1/genética , Factores de Transcripción/genética , Proteínas WT1/genética , Secuenciación del Exoma , Adulto Joven
9.
Mol Genet Genomic Med ; 9(2): e1546, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33217222

RESUMEN

BACKGROUND: Wolf-Hirschhorn syndrome (WHS) (OMIM 194190) is a multiple congenital anomalies/intellectual disability syndrome. It is caused by partial loss of genetic material from the distal portion of the short arm of chromosome. METHODS: We studied the phenotype-genotype correlation. RESULTS: We present the clinical manifestations and cytogenetic results of 10 unrelated Egyptian patients with 4p deletions. Karyotyping, FISH and MLPA was performed for screening for microdeletion syndromes. Array CGH was done for two patients. All patients exhibited the cardinal clinical manifestation of WHS. FISH proved deletion of the specific WHS locus in all patients. MLPA detected microdeletion of the specific locus in two patients with normal karyotypes, while array CGH, performed for two patients, has delineated the extent of the deleted segments and the involved genes. LETM1, the main candidate gene for the seizure phenotype, was found deleted in the two patients tested by array CGH; nevertheless, one of them did not manifest seizures. The study emphasized the previous. CONCLUSION: WHS is a contiguous gene syndrome resulting from hemizygosity of the terminal 2 Mb of 4p16.3 region. The Branchial fistula, detected in one of our patients is a new finding that, to our knowledge, was not reported.


Asunto(s)
Genotipo , Fenotipo , Síndrome de Wolf-Hirschhorn/genética , Proteínas de Unión al Calcio/genética , Niño , Preescolar , Hibridación Genómica Comparativa , Femenino , Humanos , Hibridación Fluorescente in Situ , Lactante , Cariotipificación , Masculino , Proteínas de la Membrana/genética , Síndrome de Wolf-Hirschhorn/patología
10.
Proc Natl Acad Sci U S A ; 117(24): 13680-13688, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32493750

RESUMEN

Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the testis-determining gene SRY is present in many cases, the etiology is unknown in most SRY-negative patients. We performed exome sequencing on 78 individuals with 46,XX TDSD/OTDSD of unknown genetic etiology and identified seven (8.97%) with heterozygous variants affecting the fourth zinc finger (ZF4) of Wilms' tumor 1 (WT1) (p.Ser478Thrfs*17, p.Pro481Leufs*15, p.Lys491Glu, p.Arg495Gln [x3], p.Arg495Gly). The variants were de novo in six families (P = 4.4 × 10-6), and the incidence of WT1 variants in 46,XX DSD is enriched compared to control populations (P < 1.8 × 10-4). The introduction of ZF4 mutants into a human granulosa cell line resulted in up-regulation of endogenous Sertoli cell transcripts and Wt1Arg495Gly/Arg495Gly XX mice display masculinization of the fetal gonads. The phenotype could be explained by the ability of the mutated proteins to physically interact with and sequester a key pro-ovary factor ß-CATENIN, which may lead to up-regulation of testis-specific pathway. Our data show that unlike previous association of WT1 and 46,XY DSD, ZF4 variants of WT1 are a relatively common cause of 46,XX TDSD/OTDSD. This expands the spectrum of phenotypes associated with WT1 variants and shows that the WT1 protein affecting ZF4 can function as a protestis factor in an XX chromosomal context.


Asunto(s)
Trastornos Testiculares del Desarrollo Sexual 46, XX/metabolismo , Testículo/metabolismo , Proteínas WT1/metabolismo , Trastornos Testiculares del Desarrollo Sexual 46, XX/genética , Trastornos Testiculares del Desarrollo Sexual 46, XX/patología , Animales , Preescolar , Femenino , Humanos , Lactante , Masculino , Ratones , Ovario/crecimiento & desarrollo , Ovario/metabolismo , Testículo/crecimiento & desarrollo , Testículo/patología , Proteínas WT1/química , Proteínas WT1/genética , Dedos de Zinc , beta Catenina/genética , beta Catenina/metabolismo
11.
Mol Syndromol ; 11(5-6): 284-295, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33510599

RESUMEN

Monosomy 1p36 syndrome is one of the most common submicroscopic deletion syndromes, which is characterized by the presence of delayed developmental milestones, intellectual disability, and clinically recognizable dysmorphic craniofacial features. The syndrome comprises 4 cytogenetic groups including pure terminal deletions, interstitial deletions, complex rearrangements, and derivative chromosomes 1 due to unbalanced translocations, where unbalanced translocations represent the least percentage of all cases of monosomy 1p36 (7%). Most patients with monosomy 1p36 due to an unbalanced translocation can be cytogenetically diagnosed using conventional techniques. However, chromosomal microarray analysis is mandatory in these cases to detect copy number variance and size of the deletion and allows for setting a phenotype-genotype correlation. Here, we studied a 1.5-year-old female patient who showed intellectual disability, delayed milestones, hypotonia, seizures, and characteristic dysmorphic features including brachycephaly, straight eyebrows, deep-set eyes, downslanting palpebral fissures, midface hypoplasia, depressed nasal bridge, long philtrum, and pointed chin. Conventional cytogenetic analysis (CCA), microarray study, and fluorescence in situ hybridization (FISH) analysis were performed. CCA showed a translocation involving chromosomes 1 and 21, 45,XX,der(1)t(1;21)(p36.32;q21.1)dn. Microarray analysis revealed copy number losses at both 1p36 and proximal 21q. FISH confirmed the presence of the 1p36 deletion, but was not performed for 21q. We have concluded that phenotype-genotype correlation for monosomy 1p36 syndrome can be performed for the fundamental clinical manifestations; however, the final aspect of the syndrome depends on composite factors. Monosomy 1p36 due to unbalanced translocation may present either classically or with additional altered features of various severity based on the copy number variations involving different chromosomes.

12.
Sex Dev ; 13(5-6): 221-227, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32535607

RESUMEN

Ovotesticular difference of sex development (OT DSD) is a rare genetic disorder with an incidence of about 1/100,000 live births. The majority of OT DSD patients show a 46,XX karyotype, others may have 46,XX/46,XY chimerism or exhibit various mosaic sex chromosome combinations, and less commonly they may have a 46,XY karyotype. The aim of this work is to report the clinical, pathological, and karyotypic variations in OT DSD patients diagnosed among a large cohort of DSD patients. The study included 10 patients thoroughly evaluated for clinical, genital, and hormonal abnormalities and subjected to imaging studies, laparoscopy with gonadal biopsy, karyotype, and FISH analysis. The current study revealed a greater percentage of mosaic cell line combinations than previously reported and showed variable cytogenetic abnormalities, including the rare isodicentric (Y)(p11.32) abnormality and X;Y translocation. The study also revealed a unique pattern of gonadal type and combination frequencies. To our knowledge, this is the first study on OT DSD patients among a large cohort of DSD patients in Egypt and the Middle East.

13.
Cytogenet Genome Res ; 156(2): 71-79, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30273929

RESUMEN

We report on a female patient who was first evaluated at the age of 6 years with developmental delay, dysmorphic facial features, seizures, and autistic behavior. A brain CT showed complete agenesis of the corpus callosum, and EEG recorded bilateral epileptogenic foci. Karyotype analysis revealed 45,X,psu dic(14;X)(p11;p22). FISH using 14q and Xp subtelomeric probes, combined with a SHOX gene-specific probe, and centromere X and XIST gene analysis revealed ish psu dic(14;X)(D14S1420+; DXYS129-, SHOX-, DXZ1+, XIST+). Array CGH detected a 2-Mb loss at Xp22.33 and a 4.6-Mb gain at Xp22.2p22.12. The deletion contains 34 genes, of which CSF2RA and SHOX are OMIM morbid genes. The duplication also contains some OMIM morbid genes, of which CDKL5, NH5, RPS6KA3, and AP1S2 are the most important. The late replicating chromatin technique was used to detect the pattern of X inactivation in the normal X and in the translocated chromosome. The translocated X was found to be inactive in 70% of the studied blood lymphocytes with patchy extension of inactivation to chromosome 14. In conclusion, the phenotype of the patient may be partially affected by the haploinsufficiency of the genes that are known to escape X inactivation and that lie within the deleted region and by other deleted or duplicated genes on the abnormal X chromosome due to an alternative pattern of X inactivation. The phenotype of the patient was significantly aggravated and complicated by the functional monosomy of some genes on chromosome 14 due to partial spreading of inactivation and silencing of those genes. This case report indicates the importance of structural and functional studies and emphasizes the clinical importance of the follow-up of abnormal microarrays.

14.
Sex Dev ; 12(5): 211-217, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30007989

RESUMEN

Disorders of sex development (DSD) are conditions with an abnormal development of chromosomal, gonadal, or anatomical sex. Sex chromosome DSD involve conditions associated with either numerical or structural abnormalities of the sex chromosomes. This study included patients comprising a wide spectrum of presenting features suggestive of DSD and aimed at studying the frequency of sex chromosome abnormalities among 108 Egyptian DSD patients who presented to the Clinical Genetics and Endocrinology Clinics, National Research Centre (NRC) over the 2-year period of 2013 and 2014. The age of the studied patients ranged from 2 months to 39 years. The patients exhibited various presentations, including ambiguous genitalia, undescended testis, hypogonadism, short stature with Turner manifestations, primary or secondary amenorrhea, primary infertility, edema of the dorsum of the hands and feet, and dysmorphic features. The patients were subjected to detailed clinical examination, pubertal staging, and cytogenetic analysis. Our study reported a wide karyotypic diversity and a high frequency of sex chromosome DSD, reaching 44.44% (48/108). In conclusion, we showed a high incidence of sex chromosome DSD among Egyptian DSD patients with wide karyotype/phenotype diversity. The most frequent sex chromosome DSD detected among patients of the present study was Turner syndrome and variants (52.08%; 25/48) followed by Klinefelter syndrome and variants (43.75%; 21/48). Further long term studies are necessary for accurate detection of frequencies of different types of sex chromosomal anomalies and associated phenotypes.

16.
J Sex Med ; 14(9): 1165-1174, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28859874

RESUMEN

BACKGROUND: Mutations in the HSD17B3 gene are associated with a 46,XY disorder of sexual development (46,XY DSD) as a result of low testosterone production during embryogenesis. AIM: To elucidate the molecular basis of the disorder by chemically analyzing four missense mutations in HSD17B3 (T54A, M164T, L194P, G289S) from Egyptian patients with 46,XY DSD. METHODS: Expression plasmids for wild-type 17ß-hydroxysteroid hydrogenase type 3 (17ß-HSD3) and mutant enzymes generated by site-directed mutagenesis were transiently transfected into human HEK-293 cells. Protein expression was verified by western blotting and activity was determined by measuring the conversion of radiolabeled Δ4-androstene-3,17-dione to testosterone. Application of a homology model provided an explanation for the observed effects of the mutations. OUTCOMES: Testosterone formation by wild-type and mutant 17ß-HSD3 enzymes was compared. RESULTS: Mutations T54A and L194P, despite normal protein expression, completely abolished 17ß-HSD3 activity, explaining their severe 46,XY DSD phenotype. Mutant M164T could still produce testosterone, albeit with significantly lower activity compared with wild-type 17ß-HSD3, resulting in ambiguous genitalia or a microphallus at birth. The substitution G289S represented a polymorphism exhibiting comparable activity to wild-type 17ß-HSD3. Sequencing of the SRD5A2 gene in three siblings bearing the HSD17B3 G289S polymorphism disclosed the homozygous Y91H mutation in the former gene, thus explaining the 46,XY DSD presentations. Molecular modeling analyses supported the biochemical observations and predicted a disruption of cofactor binding by mutations T54A and M164T and of substrate binding by L196P, resulting in the loss of enzyme activity. In contrast, the G289S substitution was predicted to disturb neither the three-dimensional structure nor enzyme activity. CLINICAL TRANSLATION: Biochemical analysis of mutant 17ß-HSD3 enzymes is necessary to understand genotype-phenotype relationships. STRENGTHS AND LIMITATIONS: Biochemical analysis combined with molecular modeling provides insight into disease mechanism. However, the stability of mutant proteins in vivo cannot be predicted by this approach. CONCLUSION: The 17ß-HSD3 G289S substitution, previously reported in other patients with 46,XY DSD, is a polymorphism that does not cause the disorder; thus, further sequence analysis was required and disclosed a mutation in SRD5A2, explaining the cause of 46,XY DSD in these patients. Engeli RT, Tsachaki M, Hassan HA, et al. Biochemical Analysis of Four Missense Mutations in the HSD17B3 Gene Associated With 46,XY Disorders of Sex Development in Egyptian Patients. J Sex Med 2017;14:1165-1174.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas/genética , Trastorno del Desarrollo Sexual 46,XY/enzimología , Trastorno del Desarrollo Sexual 46,XY/genética , Mutación Missense , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Trastorno del Desarrollo Sexual 46,XY/sangre , Egipto , Femenino , Genotipo , Células HEK293 , Homocigoto , Humanos , Masculino , Fenotipo , Testosterona/sangre
17.
PLoS One ; 12(7): e0181297, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28686738

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0118748.].

18.
J Toxicol Environ Health A ; 80(4): 236-249, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28569618

RESUMEN

Triclosan (TCS), an antibacterial, has been shown to be an endocrine disruptor in the rat. Previously, subchronic TCS treatment to female rats was found to advance puberty and potentiate the effect of ethinyl estradiol (EE) on uterine growth when EE and TCS were co-administered prior to weaning. In the pubertal study, a decrease in serum thyroxine (T4) concentrations with no significant change in serum thyroid-stimulating hormone (TSH) was also observed. The purpose of the present study was to further characterize the influence of TCS on the reproductive and thyroid axes of the female rat using a chronic exposure regimen. Female Wistar rats were exposed by oral gavage to vehicle control, EE (1 µg/kg), or TCS (2.35, 4.69, 9.375 or 37.5 mg/kg) for 8 months and estrous cyclicity monitored. Although a divergent pattern of reproductive senescence appeared to emerge from 5 to 11 months of age between controls and EE-treated females, no significant difference in cyclicity was noted between TCS-treated and control females. A higher % control females displayed persistent diestrus (PD) by the end of the study, whereas animals administered with positive control (EE) were predominately persistent estrus (PE). Thyroxine concentration was significantly decreased in TCS-administered 9.375 and 37.5 mg/kg groups, with no marked effects on TSH levels, thyroid tissue weight, or histology. Results demonstrate that a long-term exposure to TCS did not significantly alter estrous cyclicity or timing of reproductive senescence in females but suppressed T4 levels at a lower dose than previously observed.


Asunto(s)
Envejecimiento/efectos de los fármacos , Ciclo Estral/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Reproducción/efectos de los fármacos , Glándula Tiroides/efectos de los fármacos , Triclosán/toxicidad , Animales , Antiinfecciosos Locales/toxicidad , Femenino , Ratas , Ratas Wistar , Pruebas de Toxicidad Crónica
19.
J AOAC Int ; 100(2): 387-391, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28118571

RESUMEN

An analytical method for determining the presence and levels of residual active ingredients found in neutralized suspensions of phenolic and quaternary ammonium salt-based antimicrobial products was developed using solid-phase extraction in combination with LC-tandem MS. A single-laboratory validation of the method was performed at three concentration levels for the quaternary ammonium compounds (also referred to as benzalkonium chlorides or BACs) and the phenols in the presence of letheen broth neutralizer at 2.5 and 2.75 µg/mL, respectively, as well as at dilutions of 1:10 and 1:100 in those concentrations. The method's lowest LODs were 0.005 µg/g for BACs and 0.006 µg/g for phenols. The average recovery of the fortified samples for both active ingredients ranged between 80 and 124%, and RSDs were generally <20%. In a related study, the effectiveness of letheen broth with and without sodium thiosulfate was evaluated as a neutralizer for sodium hypochlorite. The results showed that letheen broth without sodium thiosulfate neutralizes chlorine concentrations up to 60 ppm, and that 200 µg sodium thiosulfate are required to neutralize a 72 ppm concentrated chlorine solution in letheen broth.


Asunto(s)
Antiinfecciosos/análisis , Compuestos de Benzalconio/análisis , Compuestos de Bifenilo/análisis , Diclorofeno/análogos & derivados , Cromatografía por Intercambio Iónico/métodos , Medios de Cultivo/química , Diclorofeno/análisis , Lípidos/química , Fenoles/química , Hipoclorito de Sodio/química , Espectrometría de Masas en Tándem/métodos , Tiosulfatos/química
20.
Sex Dev ; 11(5-6): 280-283, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29320783

RESUMEN

WT1 gene mutations have been described in 46,XY patients with ambiguous genitalia or complete gonadal dysgenesis with or without Wilms' tumor, nephropathy, gonadoblastoma, and other defects, e.g., cryptorchidism or hypospadias. p.R462W is a hot spot mutation in exon 9 and is the most common mutation in patients with Denys-Drash syndrome. However, in this study we report an Egyptian patient with a novel phenotype carrying the p.R462W mutation. We also review the heterogeneity of phenotypes of previously reported patients with the p.R462W (previously referred to as Arg394Trp) mutation.


Asunto(s)
Trastorno del Desarrollo Sexual 46,XY/genética , Gonadoblastoma/genética , Proteínas WT1/genética , Egipto , Femenino , Humanos , Lactante , Masculino , Mutación/genética
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