RESUMEN
Thyroid dyshormonogenesis (THD) is a heterogeneous group of genetic diseases caused by the total or partial defect in the synthesis or secretion of thyroid hormones. Genetic variants in DUOX2 can cause partial to total iodination organification defects and clinical heterogeneity, from transient to permanent congenital hypothyroidism. The aim of this study was to undertake a molecular characterization and genotype-phenotype correlation in patients with THD and candidate variants in DUOX2. A total of 31 (19.38%) patients from the Catalan Neonatal Screening Program presented with variants in DUOX2 that could explain their phenotype. Fifteen (48.39%) patients were compound heterozygous, 10 (32.26%) heterozygous, and 4 (12.90%) homozygous. In addition, 8 (26.67%) of these patients presented variants in other genes. A total of 35 variants were described, 10 (28.57%) of these variants have not been previously reported in literature. The most frequent variant in our cohort was c.2895_2898del/p.(Phe966SerfsTer29), classified as pathogenic according to reported functional studies. The final diagnosis of this cohort was permanent THD in 21 patients and transient THD in 10, according to reevaluation and/or need for treatment with levothyroxine. A clear genotype-phenotype correlation could not be identified; therefore, functional studies are necessary to confirm the pathogenicity of the variants.
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Oxidasas Duales , Estudios de Asociación Genética , Humanos , Oxidasas Duales/genética , Oxidasas Duales/metabolismo , Femenino , Masculino , Recién Nacido , Disgenesias Tiroideas/genética , Disgenesias Tiroideas/patología , Fenotipo , Mutación , Genotipo , Hipotiroidismo Congénito/genética , Tamizaje Neonatal , TiroxinaRESUMEN
BACKGROUND: The prevalence of vitamin D (vitD) deficiency presenting as rickets is increasing worldwide. Insufficient sun exposure, vitD administration, and/or calcium intake are the main causes. However, vitD system-related genes may also have a role. METHODS: Prospective study: 109 rachitic children completed a 6-mo study period or until rachitic manifestations disappeared. Thirty children were selected as controls. Clinical and biochemical data were evaluated at baseline in patients and controls and biochemistry re-evaluated at radiological healing. Therapy was stratified in three different protocols. Fifty-four single-nucleotide polymorphisms (SNPs) of five vitD system genes (VDR, CP2R1, CYP27B1, CYP24A1, and GC) were genotyped and their association with clinical and biochemcial data was analyzed. RESULTS: Therapy response was similar in terms of radiological healing although it was not so in terms of biochemical normalization. Only VDR gene (promoter, start-codon, and intronic genotypes) was rickets-associated in terms of serum 25-OH-D, calcium, radiological severity and time needed to heal. Eight patients with sufficient calcium intake and 25-OH-D levels carried a VDR genotype lacking minor allele homozygous genotypes at SNPs spread along the gene. CONCLUSION: Although patients presented epidemiologic factors strongly contributing to rickets, genetic modulation affecting predisposition, severity, and clinical course is exerted, at least in part, by VDR gene polymorphic variation.
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Calcio/sangre , Trastornos de la Nutrición del Niño/genética , Raquitismo/diagnóstico , Raquitismo/genética , Deficiencia de Vitamina D/genética , Vitamina D/sangre , 25-Hidroxivitamina D3 1-alfa-Hidroxilasa/genética , Alelos , Estudios de Casos y Controles , Ciencias de la Nutrición del Niño , Preescolar , Colestanotriol 26-Monooxigenasa/genética , Familia 2 del Citocromo P450/genética , Femenino , Genotipo , Homocigoto , Humanos , Lactante , Masculino , Polimorfismo de Nucleótido Simple , Estudios Prospectivos , Receptores de Calcitriol/genética , Proteína de Unión a Vitamina D/genética , Vitamina D3 24-Hidroxilasa/genéticaRESUMEN
OBJECTIVE: The steroidogenic acute regulatory protein (StAR) transports cholesterol to the mitochondria for steroidogenesis. Loss of StAR function causes lipoid congenital adrenal hyperplasia (LCAH) which is characterized by impaired synthesis of adrenal and gonadal steroids causing adrenal insufficiency, 46,XY disorder of sex development (DSD) and failure of pubertal development. Partial loss of StAR activity may cause adrenal insufficiency only. PATIENT: A newborn girl was admitted for mild dehydration, hyponatremia, hyperkalemia and hypoglycaemia and had normal external female genitalia without hyperpigmentation. Plasma cortisol, 17OH-progesterone, DHEA-S, androstendione and aldosterone were low, while ACTH and plasma renin activity were elevated, consistent with the diagnosis of primary adrenal insufficiency. Imaging showed normal adrenals, and cytogenetics revealed a 46,XX karyotype. She was treated with fluids, hydrocortisone and fludrocortisone. DESIGN, METHODS AND RESULTS: Genetic studies revealed a novel homozygous STAR mutation in the 3' acceptor splice site of intron 4, c.466-1G>A (IVS4-1G>A). To test whether this mutation would affect splicing, we performed a minigene experiment with a plasmid construct containing wild-type or mutant StAR gDNA of exons-introns 4-6 in COS-1 cells. The splicing was assessed on total RNA using RT-PCR for STAR cDNAs. The mutant STAR minigene skipped exon 5 completely and changed the reading frame. Thus, it is predicted to produce an aberrant and shorter protein (p.V156GfsX19). Computational analysis revealed that this mutant protein lacks wild-type exons 5-7 which are essential for StAR-cholesterol interaction. CONCLUSIONS: STAR c.466-1A skips exon 5 and causes a dramatic change in the C-terminal sequence of the protein, which is essential for StAR-cholesterol interaction. This splicing mutation is a loss-of-function mutation explaining the severe phenotype of our patient. Thus far, all reported splicing mutations of STAR cause a severe impairment of protein function and phenotype.
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Hiperplasia Suprarrenal Congénita/genética , Empalme Alternativo/genética , Trastorno del Desarrollo Sexual 46,XY/genética , Mutación , Fosfoproteínas/genética , Hiperplasia Suprarrenal Congénita/patología , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/genética , Animales , Sitios de Unión/genética , Células COS , Chlorocebus aethiops , Colesterol/química , Colesterol/metabolismo , Trastorno del Desarrollo Sexual 46,XY/patología , Exones/genética , Femenino , Humanos , Recién Nacido , Modelos Moleculares , Fenotipo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Unión Proteica , Estructura Terciaria de ProteínaRESUMEN
Introduction: Defects in any thyroid hormone synthesis steps cause thyroid dyshormonogenesis (THD). THD due to thyroglobulin (TG) gene variants is a cause of congenital hypothyroidism (CH) with a wide clinical spectrum, ranging from mild to severe permanent hypothyroidism. We present high-throughput sequencing results of patients with TG variants. Methods: A CH high-throughput sequencing-panel of the main genes involved in the regulation of thyroid hormonogenesis was performed to identify those TG variants that may be related to patient THD phenotype. Results: We identified 21 TG gene variants in 19 patients (11.8%) which could explain their phenotype. Ten of those (47.6%) were not previously described. CH was biochemically severe in these 19 patients. Eight of them were reevaluated after one month of discontinuing LT4 treatment and all had severe permanent hypothyroidism. We also identified another 16 patients who presented heterozygous TG variants, of whom, at reevaluation, five had mild permanent and only one had severe permanent hypothyroidisms. Discussions: In this study, 10 novel and 11 previously reported variants in the TG gene have been identified that could explain the phenotype of 19 patients from non-consanguineous families from a large THD cohort. Although not all these TG gene variants can explain all the patients' THD phenotypes, some of them had severe or mild permanent hypothyroidism at reevaluation.
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Hipotiroidismo Congénito , Tiroglobulina , Humanos , Tiroglobulina/genética , Femenino , Masculino , Hipotiroidismo Congénito/genética , Niño , Preescolar , Secuenciación de Nucleótidos de Alto Rendimiento , Fenotipo , Lactante , Disgenesias Tiroideas/genética , Mutación , Adolescente , Adulto , Recién NacidoRESUMEN
We report a novel RPGR missense variant co-segregated with a familial X-linked retinitis pigmentosa (XLRP) case. The brothers were hemizygous for this variant, but only the proband presented with primary ciliary dyskinesia (PCD). Thus, we aimed to elucidate the role of the RPGR variant and other modifier genes in the phenotypic variability observed in the family and its impact on motile cilia. The pathogenicity of the variant on the RPGR protein was evaluated by in vitro studies transiently transfecting the mutated RPGR gene, and immunofluorescence analysis on nasal brushing samples. Whole-exome sequencing was conducted to identify potential modifier variants. In vitro studies showed that the mutated RPGR protein could not localise to the cilium and impaired cilium formation. Accordingly, RPGR was abnormally distributed in the siblings' nasal brushing samples. In addition, a missense variant in CEP290 was identified. The concurrent RPGR variant influenced ciliary mislocalisation of the protein. We provide a comprehensive characterisation of motile cilia in this XLRP family, with only the proband presenting PCD symptoms. The variant's pathogenicity was confirmed, although it alone does not explain the respiratory symptoms. Finally, the CEP290 gene may be a potential modifier for respiratory symptoms in patients with RPGR mutations.
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Trastornos de la Motilidad Ciliar , Retinitis Pigmentosa , Humanos , Masculino , Trastornos de la Motilidad Ciliar/genética , Proteínas del Ojo/metabolismo , Genes Modificadores , Mutación , Retinitis Pigmentosa/genéticaRESUMEN
CONTEXT: IGF-I is essential for normal human growth and mediates its effects through the IGF1R. IGF1R mutations have been associated with varying degrees of intrauterine and postnatal growth retardation. OBJECTIVE: To identify IGF1R gene mutations in a short-statured family with intrauterine growth retardation and microcephaly. METHODS: Direct DNA sequencing was used to identify IGF1R mutations. Multiplex ligation-dependent probe amplification analyses were performed for deletions and duplications of all IGF1R exons. Functional studies were conducted to assess mutation pathogenicity. RESULTS: A novel heterozygous IGF1R missense mutation in exon 7 (c.A1549T, p.Y487F) was identified in a short-statured girl with severe prenatal growth retardation and microcephaly. The same mutation was also identified in her mother, who presented prenatal and postnatal growth failure, and her short-statured maternal grandmother, both of whom exhibited microcephaly. The index case showed a partial response to rhGH. Functional studies performed in dermal fibroblasts from the index case and her mother showed normal IGF-I binding; however, IGF-I activation of intracellular signalling measured as AKT and extracellular signal-regulated kinase phosphorylation was markedly reduced, with patients' values being lower than those of her mother. IGF-I stimulation of DNA synthesis was significantly reduced compared with controls. CONCLUSION: Our results show a novel missense mutation in the IGF1R gene (c.A1549T, p.Y487F) associated with prenatal and postnatal growth failure and microcephaly in the context of familial short stature. The functional studies are in line with the inactivation of one copy of the IGF1R gene with variable expression within the same family.
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Retardo del Crecimiento Fetal/genética , Mutación Missense/genética , Receptor IGF Tipo 1/genética , Adulto , Niño , ADN , Análisis Mutacional de ADN , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Microcefalia , Persona de Mediana Edad , Linaje , Embarazo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismoRESUMEN
CONTEXT: Patients with congenital hyperinsulinism due to ABCC8 variants generally present severe hypoglycemia and those who do not respond to medical treatment typically undergo pancreatectomy. Few data exist on the natural history of non-pancreatectomized patients. OBJECTIVE: This work aims to describe the genetic characteristics and natural history in a cohort of non-pancreatectomized patients with congenital hyperinsulinism due to variants in the ABCC8 gene. METHODS: Ambispective study of patients with congenital hyperinsulinism with pathogenic or likely pathogenic variants in ABCC8 treated in the last 48 years and who were not pancreatectomized. Continuous glucose monitoring (CGM) has been periodically performed in all patients since 2003. An oral glucose tolerance test was performed if hyperglycemia was detected in the CGM. RESULTS: Eighteen non-pancreatectomized patients with ABCC8 variants were included. Seven (38.9%) patients were heterozygous, 8 (44.4%) compound heterozygous, 2 (11.1%) homozygous, and 1 patient carried 2 variants with incomplete familial segregation studies. Seventeen patients were followed up and 12 (70.6%) of them evolved to spontaneous resolution (median age 6.0 ± 4 years; range, 1-14). Five of these 12 patients (41.7%) subsequently progressed to diabetes with insufficient insulin secretion. Evolution to diabetes was more frequent in patients with biallelic variants in the ABCC8 gene. CONCLUSION: The high remission rate observed in our cohort makes conservative medical treatment a reliable strategy for the management of patients with congenital hyperinsulinism due to ABCC8 variants. In addition, a periodic follow-up of glucose metabolism after remission is recommended, as a significant proportion of patients evolved to impaired glucose tolerance or diabetes (biphasic phenotype).
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Hiperinsulinismo Congénito , Diabetes Mellitus , Niño , Preescolar , Humanos , Glucemia , Automonitorización de la Glucosa Sanguínea , Hiperinsulinismo Congénito/complicaciones , Hiperinsulinismo Congénito/genética , Hiperinsulinismo Congénito/cirugía , Diabetes Mellitus/etiología , Diabetes Mellitus/genética , Hiperinsulinismo/genética , Mutación , Receptores de Sulfonilureas/genética , Pancreatectomía/efectos adversosRESUMEN
OBJECTIVE: Molecular causes of isolated severe growth hormone deficiency (ISGHD) in several genes have been established. The aim of this study was to analyse the contribution of growth hormone-releasing hormone receptor (GHRHR) gene sequence variation to GH deficiency in a series of prepubertal ISGHD patients and to normal adult height. DESIGN, SUBJECTS AND MEASUREMENTS: A systematic GHRHR gene sequence analysis was performed in 69 ISGHD patients and 60 normal adult height controls (NAHC). Four GHRHR single-nucleotide polymorphisms (SNPs) were genotyped in 248 additional NAHC. An analysis was performed on individual SNPs and combined genotype associations with diagnosis in ISGHD patients and with height-SDS in NAHC. RESULTS: Twenty-one SNPs were found. P3, P13, P15 and P20 had not been previously described. Patients and controls shared 12 SNPs (P1, P2, P4-P11, P16 and P21). Significantly different frequencies of the heterozygous genotype and alternate allele were detected in P9 (exon 4, rs4988498) and P12 (intron 6, rs35609199); P9 heterozygous genotype frequencies were similar in patients and the shortest control group (heights between -2 and -1 SDS) and significantly different in controls (heights between -1 and +2 SDS). GHRHR P9 together with 4 GH1 SNP genotypes contributed to 6·2% of height-SDS variation in the entire 308 NAHC. CONCLUSIONS: This study established the GHRHR gene sequence variation map in ISGHD patients and NAHC. No evidence of GHRHR mutation contribution to ISGHD was found in this population, although P9 and P12 SNP frequencies were significantly different between ISGHD and NAHC. Thus, the gene sequence may contribute to normal adult height, as demonstrated in NAHC.
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Enanismo Hipofisario/genética , Variación Genética/genética , Receptores de Neuropéptido/genética , Receptores de Hormona Reguladora de Hormona Hipofisaria/genética , Estatura/genética , Estatura/fisiología , Niño , Enanismo Hipofisario/sangre , Hormona de Crecimiento Humana/sangre , Humanos , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
The palmitoylation of the Hedgehog (Hh) family of morphogens, named sonic hedgehog (SHH), desert hedgehog (DHH), and Indian hedgehog (IHH), is crucial for effective short- and long-range signaling. The hedgehog acyltransferase (HHAT) attaches the palmitate molecule to the Hh; therefore, variants in HHAT cause a broad spectrum of phenotypes. A missense HHAT novel variant c.1001T>A/p.(Met334Lys) was described in a patient first referred for a 46,XY different sexual development with partial gonadal dysgenesis but with microcephaly, eye defects, and distal phalangeal hypoplasia of both thumbs. The in silico analysis of the variant predicted an affectation of the nearest splicing site. Thus, in vitro minigene studies were carried out, which demonstrated that the variant does not affect the splicing. Subsequent protein in silico studies supported the pathogenicity of the variant, and, in conclusion, this was considered the cause of the patient's phenotype.
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Disgenesia Gonadal , Microcefalia , Humanos , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Microcefalia/complicaciones , Microcefalia/genética , Pulgar , Desarrollo Sexual , Aciltransferasas/genéticaRESUMEN
BACKGROUND: Children's diffuse lung disease, also known as children's Interstitial Lung Diseases (chILD), are a heterogeneous group of rare diseases with relevant morbidity and mortality, which diagnosis and classification are very complex. Epidemiological data are scarce. The aim of this study was to analyse incidence and prevalence of chILD in Spain. METHODS: Multicentre observational prospective study in patients from 0 to 18 years of age with chILD to analyse its incidence and prevalence in Spain, based on data reported in 2018 and 2019. RESULTS: A total of 381 cases with chILD were notified from 51 paediatric pulmonology units all over Spain, covering the 91.7% of the paediatric population. The average incidence of chILD was 8.18 (CI 95% 6.28-10.48) new cases/million of children per year. The average prevalence of chILD was 46.53 (CI 95% 41.81-51.62) cases/million of children. The age group with the highest prevalence were children under 1 year of age. Different types of disorders were seen in children 2-18 years of age compared with children 0-2 years of age. Most frequent cases were: primary pulmonary interstitial glycogenosis in neonates (17/65), neuroendocrine cell hyperplasia of infancy in infants from 1 to 12 months (44/144), idiopathic pulmonary haemosiderosis in children from 1 to 5 years old (13/74), hypersensitivity pneumonitis in children from 5 to 10 years old (9/51), and scleroderma in older than 10 years old (8/47). CONCLUSIONS: We found a higher incidence and prevalence of chILD than previously described probably due to greater understanding and increased clinician awareness of these rare diseases.
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A wide variation in height gain rate is observed in children small for gestational age (SGA) treated with growth hormone (GH). The aim of this study was to evaluate prepubertal and pubertal growth, height gain attained at adult age and to assess potential predictive factors in catch-up growth. Changes in metabolic profile were also analyzed. PATIENTS AND METHODS: Seventy-eight children born SGA were treated with a GH median dose of 33.0±2.8mcg/kg/day at a mean age of 7.3±2.0 (boys) and 6.0±1.8 (girls). RESULTS: Mean height (SDS) at GH onset was -3.31±0.7 for boys and -3.48±0.7 for girls. According to age at pubertal growth spurt onset patients were classified in their pubertal maturity group. Adult height attained expressed in SDS was -1.75±0.7 for boys and -1.69±1.0 for girls, both below the range of their mid-parental height. The greatest height gain occurred during the prepubertal period. Patients with greater height gain were lighter (p<0.001), shorter (p=0.005), and younger (p=0.02) at the start of GH, and also showed a greater increase in growth velocity during the first year on GH (p<0.001). SGA children started puberty at the same age and with the same distribution into pubertal maturity group as the reference population. No relevant GH-related adverse events were reported, including in the insulin resistance parameters evaluated. Differences were found in fasting plasma glucose values, but were without clinical relevance. IGF-I plasma values remained within the safety range. CONCLUSIONS: GH therapy is safe and beneficial for SGA children. The response to GH therapy is widely heterogeneous, suggesting that GH should be started at a young age and the GH dose prescribed should be individualized. SGA children started puberty at the same age as the reference population. The only factor that predicts greater adult height is growth velocity during the first year of therapy.
RESUMEN
A wide variation in height gain rate is observed in children small for gestational age (SGA) treated with growth hormone (GH). The aim of this study was to evaluate prepubertal and pubertal growth, height gain attained at adult age and to assess potential predictive factors in catch-up growth. Changes in metabolic profile were also analyzed. PATIENTS AND METHODS: Seventy-eight children born SGA were treated with a GH median dose of 33.0±2.8mcg/kg/day at a mean age of 7.3±2.0 (boys) and 6.0±1.8 (girls). RESULTS: Mean height (SDS) at GH onset was -3.31±0.7 for boys and -3.48±0.7 for girls. According to age at pubertal growth spurt onset patients were classified in their pubertal maturity group. Adult height attained expressed in SDS was -1.75±0.7 for boys and -1.69±1.0 for girls, both below the range of their mid-parental height. The greatest height gain occurred during the prepubertal period. Patients with greater height gain were lighter (p<0.001), shorter (p=0.005), and younger (p=0.02) at the start of GH, and also showed a greater increase in growth velocity during the first year on GH (p<0.001). SGA children started puberty at the same age and with the same distribution into pubertal maturity group as the reference population. No relevant GH-related adverse events were reported, including in the insulin resistance parameters evaluated. Differences were found in fasting plasma glucose values, but were without clinical relevance. IGF-I plasma values remained within the safety range. CONCLUSIONS: GH therapy is safe and beneficial for SGA children. The response to GH therapy is widely heterogeneous, suggesting that GH should be started at a young age and the GH dose prescribed should be individualized. SGA children started puberty at the same age as the reference population. The only factor that predicts greater adult height is growth velocity during the first year of therapy.
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Hormona de Crecimiento Humana , Recién Nacido Pequeño para la Edad Gestacional , Metaboloma , Pubertad , Adolescente , Adulto , Estatura , Niño , Preescolar , Femenino , Hormona de Crecimiento Humana/uso terapéutico , Humanos , Recién Nacido , MasculinoRESUMEN
PURPOSE: Thyroid dyshormonogenesis is a heterogeneous group of hereditary diseases produced by a total/partial blockage of the biochemical processes of thyroid-hormone synthesis and secretion. Paired box 8 (PAX8) is essential for thyroid morphogenesis and thyroid hormone synthesis. We aimed to identify PAX8 variants in patients with thyroid dyshormonogenesis and to analyze them with in vitro functional studies. PATIENTS AND METHODS: Nine pediatric patients with a eutopic thyroid gland were analyzed by the Catalan screening program for congenital hypothyroidism. Scintigraphies showed absent, low, or normal uptake. Only one patient had a hypoplastic gland. On reevaluation, perchlorate discharge test was negative or compatible with partial iodine-organization deficit. After evaluation, 8 patients showed permanent mild or severe hypothyroidism. Massive-sequencing techniques were used to detect variants in congenital hypothyroidism-related genes. In vitro functional studies were based on transactivating activity of mutant PAX8 on a TG-gene promoter and analyzed by a dual-luciferase assays. RESULTS: We identified 7 heterozygous PAX8 exonic variants and 1 homozygous PAX8 splicing variant in 9 patients with variable phenotypes of thyroid dyshormonogenesis. Five were novel and 5 variants showed a statistically significant impaired transcriptional activity of TG promoter: 51% to 78% vs the wild type. CONCLUSIONS: Nine patients presented with PAX8 candidate variants. All presented with a eutopic thyroid gland and 7 had deleterious variants. The phenotype of affected patients varies considerably, even within the same family; but, all except the homozygous patient presented with a normal eutopic thyroid gland and thyroid dyshormonogenesis. PAX8 functional studies have shown that 6 PAX8 variants are deleterious. Our studies have proven effective in evaluating these variants.
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Hipotiroidismo Congénito/genética , Factor de Transcripción PAX8/genética , Glándula Tiroides/fisiología , Adolescente , Variación Biológica Poblacional , Niño , Hipotiroidismo Congénito/diagnóstico , Hipotiroidismo Congénito/tratamiento farmacológico , Hipotiroidismo Congénito/fisiopatología , Femenino , Estudios de Seguimiento , Terapia de Reemplazo de Hormonas , Humanos , Lactante , Recién Nacido , Masculino , Mutación , Tamizaje Neonatal , Fenotipo , Pruebas de Función de la Tiroides , Glándula Tiroides/diagnóstico por imagen , Glándula Tiroides/patología , Tiroxina/uso terapéuticoRESUMEN
INTRODUCTION: Primary ciliary dyskinesia (PCD) is characterized by an alteration in the ciliary structure causing difficulty in the clearance of respiratory secretions. Diagnosis is complex and based on a combination of techniques. The objective of this study was to design a gene panel including all known causative genes, and to corroborate their diagnostic utility in a cohort of Spanish patients. METHODS: This was a multicenter cross-sectional study of patients with a high suspicion of PCD, according to European Respiratory Society criteria, designed around a gene panel for massive sequencing using SeqCap EZ capture technology that included 44 genes associated with PCD. RESULTS: We included 79 patients, 53 of whom had a diagnosis of confirmed or highly probable PCD. The sensitivity of the gene panel was 81.1%, with a specificity of 100%. Candidate variants were found in some of the genes of the panel in 43 patients with PCD, 51.2% (22/43) of whom were homozygotes and 48.8% (21/43) compound heterozygotes. The most common causative genes were DNAH5 and CCDC39. We found 52 different variants, 36 of which were not previously described in the literature. CONCLUSIONS: The design and implementation of a tailored gene panel produces a high yield in the genetic diagnosis of PCD. This panel provides a better understanding of the causative factors involved in these patients and lays down the groundwork for future therapeutic approaches.
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Síndrome de Kartagener , Estudios Transversales , Homocigoto , Humanos , Síndrome de Kartagener/diagnóstico , MutaciónRESUMEN
Primary microcephaly (MCPH) is a genetically heterogeneous disorder showing an autosomal recessive mode of inheritance. Patients with MCPH present head circumference values two or three standard deviations (SDs) significantly below the mean for age- and sex-matched populations. MCPH is associated with a nonprogressive mild to severe intellectual disability, with normal brain structure in most patients, or with a small brain and gyri without visceral malformations. We present the case of an adult patient born from Argentinian nonconsanguineous healthy parents. He had a head circumference >5 SD below the mean, cerebral neuroimaging showing hypoplasia of the corpus callosum, bilateral migration disorder with heterotopia of the sylvian fissure and colpocephaly. The patient was compound heterozygous for pathogenic variants in the CENPJ gene (c.289dupA inherited from his mother and c.1132 C > T inherited from his father). Our patient represents an uncommon situation for the usual known context of CENPJ and MCPH, including family origin (Argentinian), pedigree (nonconsanguineous), and genotype (a compound heterozygous case with two variants predicting a truncated protein). Next-generation sequencing studies applied in a broader spectrum of clinical presentations of MCPH syndromes may discover additional similar patients and families.
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CONTEXT: Mutations in cytochrome P450 oxidoreductase (POR) cause a form of congenital adrenal hyperplasia (CAH). We report a novel R550W mutation in POR identified in a 46,XX patient with signs of aromatase deficiency. OBJECTIVE: Analysis of aromatase deficiency from the R550W mutation in POR. DESIGN, SETTING, AND PATIENT: Both the child and the mother had signs of virilization. Ultrasound revealed the presence of uterus and ovaries. No defects in CYP19A1 were found, but further analysis with a targeted Disorders of Sexual Development NGS panel (DSDSeq.V1, 111 genes) on a NextSeq (Illumina) platform in Madrid and Barcelona, Spain, revealed compound heterozygous mutations c.73_74delCT/p.L25FfsTer93 and c.1648C > T/p.R550W in POR. Wild-type and R550W POR were produced as recombinant proteins and tested with multiple cytochrome P450 enzymes at University Children's Hospital, Bern, Switzerland. MAIN OUTCOME MEASURE AND RESULTS: POR-R550W showed 41% of the WT activity in cytochrome c and 7.7% activity for reduction of MTT. Assays of CYP19A1 showed a severe loss of activity, and CYP17A1 as well as CYP21A2 activities were also lost by more than 95%. Loss of CYP2C9, CYP2C19, and CYP3A4 activities was observed for the R550W-POR. Predicted adverse effect on aromatase activity as well as a reduction in binding of NADPH was confirmed. CONCLUSIONS: Pathological effects due to POR-R550W were identified, expanding the knowledge of molecular pathways associated with aromatase deficiency. Screening of the POR gene may provide a diagnosis in CAH without defects in genes for steroid metabolizing enzymes.
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Trastornos del Desarrollo Sexual 46, XX/patología , Hiperplasia Suprarrenal Congénita/patología , Aromatasa/deficiencia , Aromatasa/genética , Mutación , Trastornos del Desarrollo Sexual 46, XX/genética , Hiperplasia Suprarrenal Congénita/genética , Niño , Femenino , Humanos , Masculino , Linaje , Fenotipo , PronósticoRESUMEN
Primary ciliary dyskinesia (PCD) is an autosomal recessive rare disease caused by an alteration of ciliary structure. Immunofluorescence, consisting in the detection of the presence and distribution of cilia proteins in human respiratory cells by fluorescence, has been recently proposed as a technique to improve understanding of disease-causing genes and diagnosis rate in PCD. The objective of this study is to determine the accuracy of a panel of four fluorescently labeled antibodies (DNAH5, DNALI1, GAS8 and RSPH4A or RSPH9) as a PCD diagnostic tool in the absence of transmission electron microscopy analysis. The panel was tested in nasal brushing samples of 74 patients with clinical suspicion of PCD. Sixty-eight (91.9%) patients were evaluable for all tested antibodies. Thirty-three cases (44.6%) presented an absence or mislocation of protein in the ciliary axoneme (15 absent and 3 proximal distribution of DNAH5 in the ciliary axoneme, 3 absent DNAH5 and DNALI1, 7 absent DNALI1 and cytoplasmatic localization of GAS8, 1 absent GAS8, 3 absent RSPH9 and 1 absent RSPH4A). Fifteen patients had confirmed or highly likely PCD but normal immunofluorescence results (68.8% sensitivity and 100% specificity). In conclusion, immunofluorescence analysis is a quick, available, low-cost and reliable diagnostic test for PCD, although it cannot be used as a standalone test.
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BACKGROUND: Age at pubertal growth spurt (PGS) onset varies and is sex-dependent. We present anthropometric pubertal growth data for five 1-year interval age maturity groups: very early, early, intermediate, late and very late. METHODS: Longitudinal growth study of 458 healthy children (223 boys, 235 girls). Ages at PGS onset and at adult height attainment, total pubertal growth (TPG), and peak height velocity (PHV) were evaluated. PGS begins between the ages of 10 and 15 in boys and 8 and 13 in girls; children were allocated to the corresponding 1-year interval age maturity group. RESULTS: For each sex, the earlier the start of PGS onset, the higher were PHV and TPG gain. However, adult heights were similar among the five pubertal maturity groups. Height SDS values for mean values of the very early, early, late and very late maturity groups calculated according to data from the five pubertal maturity groups taken together as a single group differed from zero in both sexes, mainly during the pubertal years for the very early (> +1) and very late (> -1) maturers. These differences disappeared at adult height. CONCLUSIONS: Our data might contribute to better clinical evaluation of pubertal growth according to individual pubertal maturity tempo.
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Estatura/fisiología , Pubertad/fisiología , Adolescente , Factores de Edad , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , EspañaRESUMEN
Persistent müllerian duct syndrome (PMDS) is characterized by the presence of müllerian duct derivatives in otherwise phenotypically normal males. Homozygous or compound heterozygous alterations in AMH or AMHR2 have been identified in approximately 88% of PMDS cases. We report on a male patient with bilateral undescended gonads, müllerian derivatives, and normal serum AMH levels. A novel homozygous missense mutation, c.119G>C;p.Gly40Ala, in exon 2 of AMHR2 was detected that supported the clinical diagnosis of PMDS.
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Trastorno del Desarrollo Sexual 46,XY/genética , Mutación/genética , Receptores de Péptidos/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Trastorno del Desarrollo Sexual 46,XY/diagnóstico por imagen , Homocigoto , Humanos , Lactante , Recién Nacido , Laparoscopía , MasculinoRESUMEN
Disorders/differences of sex development (DSD) are the result of a discordance between chromosomal, gonadal, and genital sex. DSD may be due to mutations in any of the genes involved in sex determination and development in general, as well as gonadal and/or genital development specifically. MAMLD1 is one of the recognized DSD genes. However, its role is controversial as some MAMLD1 variants are present in normal individuals, several MAMLD1 mutations have wild-type activity in functional studies, and the Mamld1-knockout male mouse presents with normal genitalia and reproduction. We previously tested nine MAMLD1 variants detected in nine 46,XY DSD patients with broad phenotypes for their functional activity, but none of the mutants, except truncated L210X, had diminished transcriptional activity on known target promoters CYP17A1 and HES3. In addition, protein expression of MAMLD1 variants was similar to wild-type, except for the truncated L210X. We hypothesized that MAMLD1 variants may not be sufficient to explain the phenotype in 46,XY DSD individuals, and that further genetic studies should be performed to search for additional hits explaining the broad phenotypes. We therefore performed whole exome sequencing (WES) in seven of these 46,XY patients with DSD and in one 46,XX patient with ovarian insufficiency, who all carried MAMLD1 variants. WES data were filtered by an algorithm including disease-tailored lists of MAMLD1-related and DSD-related genes. Fifty-five potentially deleterious variants in 41 genes were identified; 16/55 variants were reported in genes in association with hypospadias, 8/55 with cryptorchidism, 5/55 with micropenis, and 13/55 were described in relation with female sex development. Patients carried 1-16 variants in 1-16 genes together with their MAMLD1 variation. Network analysis of the identified genes revealed that 23 genes presented gene/protein interactions with MAMLD1. Thus, our study shows that the broad phenotypes of individual DSD might involve multiple genetic variations contributing towards the complex network of sexual development.