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Neurofibromatosis type 1 (NF1) is caused by mutations in the NF1 gene. This retrospective study aims to evaluate the clinical manifestations and brain magnetic resonance images (MRI) analysis in 60 genetically confirmed NF1 patients. The results of next-generation sequencing (NGS), Sanger sequencing, and MLPA of NF1 gene were evaluated. A total of 54 different variants were identified. Fourteen out of them were novel variants (25.9%). Patients who complied with NIH criteria had most frequently frameshift variants (11/32 patients), and those with only CALMs had missense variants (9/28 patients). Neurofibromatosis type 1 bright objects (NBOs) on T2-weighted MRI were detected in 42 patients (42/56; 75%). These brain lesions were detected mostly in basal ganglia and in cerebellar vermis. NBOs were detected more in the patients who complied with NIH criteria (80.6%) compared to those who were only CALMs (68%). While frameshift variants (33.3%) were the most common type variants in the patients who had NBOs, the most common variants were splicing (35.7%) and missense (35.7%) variants in the patients whose MRIs were normal. Frameshift variants (11/28 patients; 39.3%) were the most common in the patients with more than one brain locus involvement. Therefore, we consider that frameshift variants may be associated with increased incidence of NBOs and involvement of more than one brain locus. In addition, NBOs may occur less frequently in the patients with splicing variants. To our knowledge, this is the first study evaluated the relationship between NF1 gene variants and NBOs. Future studies may help us understand the etiology of NBOs.
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Neurofibromatosis 1 , Encéfalo/diagnóstico por imagen , Genes de Neurofibromatosis 1 , Humanos , Imagen por Resonancia Magnética , Neurofibromatosis 1/diagnóstico por imagen , Neurofibromatosis 1/genética , Neurofibromina 1 , Estudios RetrospectivosRESUMEN
INTRODUCTION: Persistent müllerian duct syndrome (PMDS) is a rare form of 46, XY disorder of sex development characterized by the persistence of the müllerian structures (uterus, fallopian tubes, the upper part of the vagina) in phenotypically and genotypically normal males. This disease occurs as a result of impairment in the synthesis, release or effect of anti-Müllerian hormone (AMH) during the embryonic period. Approximately 85-88% of PMDS cases have been reported to have AMH or AMHRII mutation. CASE: Herein, we report two PMDS cases from unrelated two families who presented with bilateral undescended testes, persistence of müllerian remnants, and low/undetectable serum AMH levels. Molecular genetic analysis revealed two homozygous variants in AMH. The first one is a novel missense variant (c.1315C > T), the latter is a frameshift variant caused by a deletion (c.343_344delCT), which is less frequently reported type in AMH. CONCLUSION: The diagnosis of PMDS should be kept in mind in patients with externally normal males, bilateral cryptorchidism, and signs of müllerian remnants on laparoscopy.
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Hormona Antimülleriana/genética , Trastorno del Desarrollo Sexual 46,XY/genética , Preescolar , Mutación del Sistema de Lectura , Humanos , Lactante , Masculino , Mutación MissenseRESUMEN
OBJECTIVE: To evaluate orodental, facial, clinical and molecular characteristics of the patients with Noonan Syndrome (NS). STUDY DESIGN: The orodental, clinical and molecular characteristics of 29 mutation-positive patients with NS were recorded. Orodental examination was performed in 17 patients. All exons and exonintron boundries of PTPN11 and SOS1 genes were analyzed by Sanger sequencing. RESULTS: A total of 29 patients with NS from 27 unrelated families were included in the study. Seventeen patients were examined by a specialist in oral medicine. The most common orodental findings were high-arched palate (n=13), gingivitis (n=6) and severe caries (n=6). Anterior open bite, posterior cross bite, Class II malocclusion, hypodontia, prognathism (maxillary or mandibular), macroglossia and gingival hyperplasia were also detected. Thirteen different mutations were observed in PTPN11 gene and exon 3 was the hotspot region. Hypodontia was detected in two patients who had the same mutation in PTPN11 gene, c.181G>A, p.D61N. CONCLUSION: This study indicated a high prevalance of orodental problems including high-arched palate, severe dental caries and gingivitis in patients with mutation-positive NS. The mutation in PTPN11 gene, c.181G>A, p.D61N, may be associated with hypodontia in patients with NS.
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Caries Dental , Síndrome de Noonan , Mordida Abierta , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Humanos , Mutación , Síndrome de Noonan/genética , Fenotipo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genéticaRESUMEN
INTRODUCTION: Microdeletion syndromes may be accompanied by immunological disorders. This study aimed to evaluate the clinical and laboratory data as well as the immune functions of patients diagnosed with a microdeletion syndrome. MATERIAL AND METHODS: 39 patients diagnosed with microdeletion syndrome who were monitored at the Pediatric Genetics and Immunology clinics at Dr. Behcet Uz Children's Hospital were included in this study. All data for this research were obtained from patient records and by individual consultation with their parents. RESULTS: Of the 39 patients, 15 were monitored for a diagnosis of Williams syndrome, 12 for DiGeorge syndrome, 4 for Prader-Willi syndrome, 2 for Wolf-Hirschhorn syndrome, 1 for a 1p36 deletion, 1 for Smith-Magenis syndrome, 2 for Trichorhinophalangeal syndrome type 2 (TRPS2), and 2 for Cri-du-chat syndrome. Of these 39 patients, 10 (25.6%) had a medical history of frequent upper respiratory tract infections. One of the cases with TRPS2 and another with Smith-Magenis syndrome had previously received intravenous antibiotic therapy for infectious disease. Five of the 12 patients with DiGeorge syndrome had low T lymphocytes. Two of the patients with DiGeorge syndrome with a history of frequent infections, with hypogammaglobinemia, and low lymphocytes were receiving regular intravenous immunoglobulin (IVIG) replacement. CONCLUSIONS: It must be taken into account that patients with microdeletion syndromes, especially those with DiGeorge syndrome, may also have immunodeficiencies; therefore, these patients should be closely monitored to prevent development of any complications.
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BACKGROUND: Triple A syndrome (MIM #231550) is associated with mutations in the AAAS gene. However, about 30% of patients with triple A syndrome symptoms but an unresolved diagnosis do not harbour mutations in AAAS. OBJECTIVE: Search for novel genetic defects in families with a triple A-like phenotype in whom AAAS mutations are not detected. METHODS: Genome-wide linkage analysis, whole-exome sequencing and functional analyses were used to discover and verify a novel genetic defect in two families with achalasia, alacrima, myopathy and further symptoms. Effect and pathogenicity of the mutation were verified by cell biological studies. RESULTS: We identified a homozygous splice mutation in TRAPPC11 (c.1893+3A>G, [NM_021942.5], g.4:184,607,904A>G [hg19]) in four patients from two unrelated families leading to incomplete exon skipping and reduction in full-length mRNA levels. TRAPPC11 encodes for trafficking protein particle complex subunit 11 (TRAPPC11), a protein of the transport protein particle (TRAPP) complex. Western blot analysis revealed a dramatic decrease in full-length TRAPPC11 protein levels and hypoglycosylation of LAMP1. Trafficking experiments in patient fibroblasts revealed a delayed arrival of marker proteins in the Golgi and a delay in their release from the Golgi to the plasma membrane. Mutations in TRAPPC11 have previously been described to cause limb-girdle muscular dystrophy type 2S (MIM #615356). Indeed, muscle histology of our patients also revealed mild dystrophic changes. Immunohistochemically, ß-sarcoglycan was absent from focal patches. CONCLUSIONS: The identified novel TRAPPC11 mutation represents an expansion of the myopathy phenotype described before and is characterised particularly by achalasia, alacrima, neurological and muscular phenotypes.
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Insuficiencia Suprarrenal/genética , Acalasia del Esófago/genética , Mutación/genética , Proteínas de Transporte Vesicular/genética , Adolescente , Insuficiencia Suprarrenal/epidemiología , Insuficiencia Suprarrenal/fisiopatología , Niño , Consanguinidad , Acalasia del Esófago/epidemiología , Acalasia del Esófago/fisiopatología , Exones/genética , Femenino , Homocigoto , Humanos , Masculino , Linaje , Sitios de Empalme de ARN/genética , Turquía/epidemiologíaRESUMEN
Background/aim: CHARGE syndrome is a rare autosomal dominant disease with multiple congenital anomalies and cognitive impairment, which is caused by mutations in the CHD7 gene. This study aimed to disclose the mild end of the phenotypic spectrum of CHARGE syndrome, which has a highly variable expressivity. Materials and methods: Twenty-one patients who had at least one of the major symptoms of CHARGE syndrome (coloboma, choanal atresia, characteristic ear anomalies, semicircular canal hypoplasia, and cranial nerve anomalies) were included in the study. All patients were tested for karyotype analysis and CHD7 gene mutation/deletion. Results: In the study population, 6 different mutations were detected in 5 patients, and 2 different polymorphisms were detected in the CHD7 gene in 3 patients. MLPA analysis of all coding exons of the CHD7 gene revealed no pathogenic deletion/duplication. Conclusion: CHARGE syndrome should be considered as a differential diagnosis to detect the mild end of the spectrum, even if the patient does not fit the criteria.
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Síndrome CHARGE , Síndrome CHARGE/diagnóstico , Síndrome CHARGE/genética , Síndrome CHARGE/patología , Síndrome CHARGE/fisiopatología , Estudios de Casos y Controles , Niño , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Humanos , Mutación/genética , FenotipoRESUMEN
Mutations in components of the major spliceosome have been described in disorders with craniofacial anomalies, e.g., Nager syndrome and mandibulofacial dysostosis type Guion-Almeida. The U5 spliceosomal complex of eight highly conserved proteins is critical for pre-mRNA splicing. We identified biallelic mutations in TXNL4A, a member of this complex, in individuals with Burn-McKeown syndrome (BMKS). This rare condition is characterized by bilateral choanal atresia, hearing loss, cleft lip and/or palate, and other craniofacial dysmorphisms. Mutations were found in 9 of 11 affected families. In 8 families, affected individuals carried a rare loss-of-function mutation (nonsense, frameshift, or microdeletion) on one allele and a low-frequency 34 bp deletion (allele frequency 0.76%) in the core promoter region on the other allele. In a single highly consanguineous family, formerly diagnosed as oculo-oto-facial dysplasia, the four affected individuals were homozygous for a 34 bp promoter deletion, which differed from the promoter deletion in the other families. Reporter gene and in vivo assays showed that the promoter deletions led to reduced expression of TXNL4A. Depletion of TXNL4A (Dib1) in yeast demonstrated reduced assembly of the tri-snRNP complex. Our results indicate that BMKS is an autosomal-recessive condition, which is frequently caused by compound heterozygosity of low-frequency promoter deletions in combination with very rare loss-of-function mutations.
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Atresia de las Coanas/genética , Sordera/congénito , Eliminación de Gen , Cardiopatías Congénitas/genética , Regiones Promotoras Genéticas/genética , Ribonucleoproteína Nuclear Pequeña U5/genética , Empalmosomas/genética , Alelos , Preescolar , Atresia de las Coanas/diagnóstico , Sordera/diagnóstico , Sordera/genética , Exosomas/genética , Facies , Femenino , Perfilación de la Expresión Génica , Frecuencia de los Genes , Genes Reporteros , Cardiopatías Congénitas/diagnóstico , Heterocigoto , Homocigoto , Humanos , Masculino , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Linaje , Fenotipo , Ribonucleoproteína Nuclear Pequeña U5/metabolismo , Análisis de Secuencia de ADN , Empalmosomas/metabolismoRESUMEN
The genetic basis of haemophagocytic lymphohistiocytosis (HLH) has not been elucidated in 10% of affected patients. In this study, we report four HLH episodes in three patients with HAX1 gene mutations. We screened the mutations associated with congenital neutropenia (CN) because the neutropenia persisted following HLH treatment. There were homozygous HAX1 mutations detected in all patients. This is the first case series of patients with CN caused by HAX1 mutation who presented with HLH. We hypothesize that severe neutropenia persists after an HLH episode in children without HLH mutations (especially infants) because these patients have CN caused by HAX1 mutations.
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Proteínas Adaptadoras Transductoras de Señales/genética , Linfohistiocitosis Hemofagocítica/genética , Mutación/genética , Síndromes Congénitos de Insuficiencia de la Médula Ósea , Femenino , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Hematínicos/uso terapéutico , Humanos , Lactante , Masculino , Neutropenia/congénito , Neutropenia/genéticaRESUMEN
Chronic neutropenia (CN) is defined as neutropenia that persists for >3 months; it is caused by a heterogeneous group of diseases in children. The aim of the present study was to evaluate the significance and clinical manifestations of CN in children at a single children's hospital. Between October 2004 and April 2014, CN patient data were evaluated retrospectively. Thirty-one patients were assessed in this study. Thirteen of them (41.9%) were younger than 12 months of age at initial diagnosis. There was no difference in the absolute number of neutrophils at diagnosis between the children aged younger than 12 months and those aged 12 months and older at CN onset. Twenty-two of the patients (70.9%) were diagnosed during treatment for acute infections. A total of 11 patients (35.5%) were hospitalized because of recurrent infections. Most of the recurrent infections occurred in the lungs (81.8%). Congenital neutropenia (CoN) was identified in 14 patients (45.1%). Eight of 14 patients (57.1%) required granulocyte-colony stimulating factor treatment, and none of them experienced adverse effects from this treatment. Fifteen patients (48.3%) were diagnosed with idiopathic neutropenia. Comparison between the idiopathic and CoN groups revealed no differences in age, the absolute number of neutrophils, or the presence of infection at diagnosis; however, differences were detected in sex and the rate of spontaneous recovery from neutropenia. Ten of the patients (32.2%) experienced spontaneous recovery from neutropenia during a follow-up period of 7 to 52 months. In current study, we found a higher CoN ratio in the CN patients compared with previous reports, which may be due to the high rate of consanguineous marriages in our country. However, the finding of CN requires several laboratory investigations, prolonged follow-up, and advanced molecular analysis, and its etiology can remain idiopathic.
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Neutropenia/diagnóstico , Neutropenia/epidemiología , Neutropenia/etiología , Adolescente , Niño , Preescolar , Enfermedad Crónica , Femenino , Humanos , Lactante , Masculino , Estudios RetrospectivosRESUMEN
OBJECTIVES: Nuclear receptor subfamily 5 group A member 1 (NR5A1) is a transcription factor critical for the development of various organs. Pathogenic variants in NR5A1 are associated with a spectrum of disorders of sex development (DSD). CASE PRESENTATION: A 15-month-old baby, raised as a girl, was referred for genital swelling and ambiguous genitalia. Born to healthy consanguineous parents, the baby had a phallus, perineal hypospadias, labial fusion, and a hypoplastic scrotum. Hormonal evaluation showed normal levels, and ultrasonography revealed small gonads and absence of Müllerian derivatives. Post-human chorionic gonadotropin (hCG) testing indicated an adequate testosterone response. The karyotype was 46,XY, and in it was found a homozygous NR5A1 variant (c.307 C>T, p.Arg103Trp) in a custom 46 XY DSD gene panel. Notably, the patient exhibited complete sex reversal, hyposplenia, and no adrenal insufficiency. CONCLUSIONS: Previously, NR5A1 pathogenic variants were considered to be dominantly inherited, and homozygous cases were thought to be associated with adrenal insufficiency. Despite the homozygous pathogenic variant, our patient showed hyposplenism with normal adrenal function; this highlights the complexity of NR5A1 genotype-phenotype correlations. These patients should be monitored for adrenal insufficiency and DSD as well as splenic function.
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Trastorno del Desarrollo Sexual 46,XY , Homocigoto , Factor Esteroidogénico 1 , Humanos , Factor Esteroidogénico 1/genética , Trastorno del Desarrollo Sexual 46,XY/genética , Femenino , Masculino , Lactante , Mutación , PronósticoRESUMEN
PURPOSE: Screening of mutations in the paired box 3 (PAX3) gene in three generations of a Turkish family with Waardenburg syndrome type 1 (WS1). METHODS: WS1 was diagnosed in a 13-month-old girl according to the WS Consortium criteria. Detailed family history of the proband revealed eight affected members in three generations. Routine clinical and audiological examination and ophthalmologic evaluation were performed on eight affected and five healthy members of the study family. Dystopia canthorum was detected in all affected patients; however, a brilliant blue iris was present in five patients who also had mild retinal hypopigmentation. Genomic DNA was extracted from the peripheral blood of affected and unaffected individuals in the family as well as 50 unrelated healthy volunteers. All coding exons and adjacent intronic regions of PAX3 were sequenced directly. RESULTS: A novel missense heterozygous c.788T>G mutation was identified in eight patients. This nucleotide alteration was not found in unaffected members of the study family or in the 50 unrelated control subjects. The mutation causes V263G amino-acid substitution in the homeodomain of the PAX3 protein, which represents the 45(th) residue of helix 3. CONCLUSIONS: We identified a novel missense c.788T>G mutation in PAX3 in a family with Waardenburg syndrome with intrafamilial phenotypic heterogeneity.
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Mutación Missense , Factores de Transcripción Paired Box/genética , Síndrome de Waardenburg/genética , Sustitución de Aminoácidos/genética , Secuencia de Bases , Estudios de Casos y Controles , Análisis Mutacional de ADN , Ojo/patología , Femenino , Tamización de Portadores Genéticos , Humanos , Lactante , Masculino , Factor de Transcripción PAX3 , Linaje , Fenotipo , Turquía , Síndrome de Waardenburg/patologíaRESUMEN
Attempted suicide with levothyroxine is very rare and has been described only in a few case reports. Although acute accidental or intentional overdoses of thyroid hormones can lead to marked elevations in serum T4 levels, many children who take as much as 5-10 mg of levothyroxine as a single dose have few or no symptoms of thyrotoxicosis. We report an adolescent girl who attempted suicide by ingesting levothyroxine. She responded well to ß-adrenergic blockade.
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Intento de Suicidio , Tirotoxicosis/inducido químicamente , Tiroxina/toxicidad , Adolescente , Antagonistas Adrenérgicos beta/uso terapéutico , Femenino , Humanos , Tirotoxicosis/diagnóstico , Tirotoxicosis/tratamiento farmacológicoRESUMEN
Marshall-Smith syndrome (MSS) and Malan syndrome (MS) are both allelic disorders caused by mutations in the NFIX gene. MS is characterized by overgrowth, intellectual disability, distinctive facial features, and accelerated skeletal maturation. On the other hand, clinical features of MSS consist of advanced bone age, dysmorphic features, intellectual disability, and failure to thrive at birth. In this study, we presented the clinical and molecular findings of two different patients with MS and MSS as a rare cause of intellectual disability and reported two novel variants in the NFIX gene. NFIX gene sequencing revealed a novel heterozygous c.1287delC (p.G430Vfs*34) mutation in patient 1 whose clinical diagnosis was compatible with Marshall-Smith syndrome, and in the second patient, physical features consistent with Malan syndrome, was detected a heterozygous one nucleotide duplication, c.303dupC (pCys102LeufsTer17).
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Discapacidad Intelectual , Recién Nacido , Humanos , Discapacidad Intelectual/complicaciones , Discapacidad Intelectual/genética , Factores de Transcripción NFI/genética , Fenotipo , Mutación/genéticaRESUMEN
Objective: Congenital hypopituitarism (CH) is a rare disease characterized by one or more hormone deficiencies of the pituitary gland. To date, many genes have been associated with CH. In this study, we identified the allelic variant spectrum of 11 causative genes in Turkish patients with CH. Materials and methods: This study included 47 patients [21 girls (44.6%) and 26 boys (55.4%)] from 45 families. To identify the genetic etiology, we screened 11 candidate genes associated with CH using next-generation sequencing. To confirm and detect the status of the specific familial variant in relatives, Sanger sequencing was also performed. Results: We identified 12 possible pathogenic variants in GHRHR, GH1, GLI2, PROP-1, POU1F1, and LHX4 in 11 patients (23.4%), of which six were novel variants: two in GHRHR, two in POU1F1, one in GLI2, and one in LHX4. In all patients, these variants were most frequently found in GLI2, followed by PROP-1 and GHRHR. Conclusion: Genetic causes were determined in only 23.4% of all patients with CH and 63% of molecularly diagnosed patients (7/11) from consanguineous families. Despite advances in genetics, we were unable to identify the genetic etiology of most patients with CH, suggesting the effect of unknown genes or environmental factors. More genetic studies are necessary to understand the etiology of CH.
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Hipopituitarismo , Femenino , Humanos , Masculino , Alelos , Hipopituitarismo/diagnóstico , Hipopituitarismo/genética , Mutación , Proteínas Nucleares/genética , Factor de Transcripción Pit-1/genética , Factores de Transcripción/genética , Proteína Gli2 con Dedos de Zinc/genéticaRESUMEN
Microcephaly-lymphedema-chorioretinal dysplasia (MLCRD) syndrome is a rare syndrome that was first described in 1992. Characteristic craniofacial features include severe microcephaly, upslanting palpebral fissures, prominent ears, a broad nose, and a long philtrum with a pointed chin. Recently, mutations in KIF11 have been demonstrated to cause dominantly inherited MLCRD syndrome. Herein, we present a patient with MLCRD syndrome whose parents were first cousins. The parents are unaffected, and thus a recessive mode of inheritance for the disorder was considered likely. However, the propositus carries a novel, de novo nonsense mutation in exon 2 of KIF11. The patient also had midline cleft tongue which has not previously been described in this syndrome.
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Cinesinas/genética , Linfedema/genética , Microcefalia/genética , Mutación , Displasia Retiniana/genética , Secuencia de Bases , Codón sin Sentido , Consanguinidad , Exones , Facies , Heterocigoto , Humanos , Lactante , Recién Nacido , Linfedema/diagnóstico , Masculino , Microcefalia/diagnóstico , Fenotipo , Displasia Retiniana/diagnóstico , TurquíaRESUMEN
Coffin-Lowry syndrome (CLS) is a rare X-linked disorder that, usually affects males, presenting with intellectual disability, short stature, growth retardation, short hands, hyperextensible fingers and progressive kyphoscoliosis. Due to skewed X chromosome inactivation, the clinical presentations of the affected females vary greatly and clinical manifestations could range from mild intellectual disability to typical features of CLS in males. Here, we reported two different novel RPS6KA3 gene mutations in two unrelated CLS patients and also described concomitant compulsive eyebrow-pulling behavior in one of these cases for the first time in the literature.
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Síndrome de Coffin-Lowry , Discapacidad Intelectual , Síndrome de Coffin-Lowry/genética , Conducta Compulsiva , Cejas , Femenino , Humanos , Discapacidad Intelectual/genética , Mutación/genéticaRESUMEN
OBJECTIVES: Non-syndromic monogenic obesity is a rare cause of early-onset severe obesity in the childhood period. The aim of this study was to screen four obesity related genes (LEP, LEPR, MC4R and POMC) in children and adolescents who had severe, non-syndromic early onset obesity. METHODS: Next-generation sequencing of all exons in LEP, LEPR, MC4R and POMC was performed in 154 children and adolescents with early onset severe obesity obesity. RESULTS: Fifteen different variants in nineteen patients were identified with a variant detection rate of 12.3%. While six different heterozygous variants were observed in MC4R gene (10/154 patients; 6.5%), five different variants in POMC gene (four of them were heterozygous and one of them was homozygous) (6/154 patients; 3.9%) and four different homozygous variants in LEPR gene (3/154 patients; 1.9%) were described. However, no variants were detected in the LEP gene. The most common pathogenic variant was c.496G>A in MC4R gene, which was detected in four unrelated patients. Six novel variants (6/15 variants; 40%) were described in seven patients. Four of them including c.233C>A and c.752T>C in MC4R gene and c.761dup and c.1221dup in LEPR gene were evaluated as pathogenic or likely pathogenic. CONCLUSIONS: In conclusion, MC4R variants are the most common genetic cause of monogenic early-onset obesity, consistent with the literature. The c.496G>A variant in MC4R gene is highly prevalent in early-onset obese patients.
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Obesidad Mórbida , Receptor de Melanocortina Tipo 4 , Adolescente , Niño , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mutación , Obesidad/genética , Obesidad Mórbida/genética , Proopiomelanocortina/genética , Receptor de Melanocortina Tipo 4/genética , Receptores de Leptina/genéticaRESUMEN
Objectives: Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive diseases characterized by salt wasting or virilization. 21 hydroxylase deficiency (21-OHD) accounts for 90-95% of all cases of CAH and caused by the genetic defects of CYP21A2. Other forms include 3-ß-hydroxysteroid dehydrogenase deficiency, 11-ß-hydroxylase deficiency (11ß-OHD) (%5-8), 17-α-hydroxylase deficiency (17α-OHD), and steroidogenic acute regulatory protein (STAR) defects (congenital lipoid adrenal hyperplasia) with mutations in HSD3B2, CYP11B1, CYP17A1, and STAR, respectively. Objectives: Herein, we aimed to present the clinical and genetic features of 64 patients with various types of CAH. Methods: Sixty-four patients with CAH, monitored in the Izmir Dr. Behcet Uz Children Hospital Division of Pediatric Endocrinology, were retrospectively analyzed for the clinical, laboratory, and genetic data. Results: Fifty-six patients (87.5%) had 21-OHD and four patients (6.3%) had 17α-OHD, three patients (4.7%) had 11ß-OHD, and one patient (1.5%) had STAR defect. The most common presenting features in 21-OHD were ambiguous genitalia. Patients with 21-OHD were diagnosed earlier than the rare groups. Disease-causing variants of CYP21A2 were identified in 46 patients. The most common mutations were IVS2, Q318X, I172N, and large deletions. Three patients with 11ß-OHD were presented with enlargement of penis and early pubic hair at the median presenting age of 26 months. 17α-OHD deficiency was detected in 4 cases. Genetic analysis revealed two different homozygous CYP17A1 variants. The patient with STAR defect was presented with dehydration and cholestasis in 44 days of the life. Genetic analysis of patient with STAR deficiency revealed a novel homozygous variant. Conclusion: The current study reported a genotype-phenotype correlation consistent with literature data in CAH cases with 21-OHD. This study also reported novel homozygous variants in STAR and CYP17A1 genes that lead to rare types of CAH.
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Dysosteosclerosis (DOS) is a rare sclerosing bone dysplasia characterized by unique osteosclerosis of the long tubular bones and platyspondyly. DOS is inherited in an autosomal recessive manner and is genetically and clinically heterogeneous. To date, four individuals with DOS who have five different TNFRSF11A mutations have been reported. Based on their data, it is hypothesized that mutations producing aberrant mutant RANK proteins (missense or truncated or elongated) cause DOS, while null mutations lead to osteopetrosis, autosomal recessive 7 (OPTB7). Herein, we present the fifth case of TNFRSF11A-associated DOS with a novel homozygous frame-shift mutation (c.19_31del; p.[Arg7CysfsTer172]). The mutation is predicted to cause nonsense mutation-mediated mRNA decay (NMD) in all RANK isoform transcripts, resulting in totally null allele. Our findings suggest genotype-phenotype relationship in TNFRSF11A-associated OPTB7 and DOS remains unclear, and that the deficiency of TNFRSF11A functions might cause DOS, rather than osteopetrosis. More data are necessary to understand the phenotypic spectrum caused by TNFRSF11A mutations.
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Autosomal recessive osteopetrosis is also known as infantile malignant osteopetrosis (IMO). The clinical course is often serious and if left untreated, it is fatal in the 1st year of life. Diagnosis is challenging and often delayed or misdiagnosed. Herein, we present an infant girl who was diagnosed with IMO during evaluations for her hypotonicity and thrombocytopenia. A novel mutation of the chloride voltage-gated channel 7 (CLCN7) gene was also reported. A 10-day-old female patient was referred to our hospital for evaluation of hypotonicity. Her physical examination was normal, other than hypotonicity. Laboratory analysis revealed thrombocytopenia and hypocalcemia. In the progress, while she was followed in outpatient clinic, hepatosplenomegaly was detected at the age of 3 months. IMO was suspected with the findings of hepatosplenomegaly, cytopenia, hypocalcemia, difficulty of obtaining bone marrow, peripheral smear findings, and hearing loss. The X-ray of the bones was consistent with IMO. A novel pathogenic homozygous c.1504>T (p.Arg502Trp) mutation in CLCN7 gene was revealed. IMO is a rare disorder and it is important to differentiate this entity for better clinical outcome. The presence of neurological and hematological findings, organomegaly, hearing loss, and vision disorders must attract attention to IMO.