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Central congenital hypothyroidism (CH) can occur as an isolated deficiency or as part of combined pituitary hormone deficiency. Unlike primary CH, central CH cannot be detected by newborn screening (NBS) using dry filter paper blood TSH levels, and early diagnosis remains challenging. In this study, the clinical and genetic backgrounds of patients with isolated central CH were determined through a questionnaire-based survey among members of the Japanese Society for Pediatric Endocrinology. The known causes of isolated central CH were studied in 14 patients, including six with previously reported patient data. The results revealed IGSF1 and TBL1X pathogenic variants in nine and one patient, respectively. All six patients with low free thyroxine (FT4) levels detected in NBS carried IGSF1 pathogenic variants. Five patients with isolated central CH diagnosed after 3 months of age were variant-negative, except for one female patient with a heterozygous IGSF1 variant. Two of the four variant-negative patients and a variant-positive patient were diagnosed with pituitary hypoplasia. One and two patients with IGSF1 variant had obesity and intellectual disability, respectively. Left amblyopia was identified in the patient with a TBL1X variant. The study revalidated that IGSF1 variants comprise the most frequent pathogenic variant in patients with isolated central CH in Japan. The neonatal period is the optimal time for the diagnosis of central CH, particularly IGSF1 abnormalities, and the introduction of T4 screening should be considered in the future, taking cost-effectiveness into consideration.
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Hipotiroidismo Congénito , Tamizaje Neonatal , Humanos , Hipotiroidismo Congénito/genética , Hipotiroidismo Congénito/diagnóstico , Hipotiroidismo Congénito/sangre , Femenino , Japón/epidemiología , Masculino , Recién Nacido , Lactante , Proteínas de la Membrana/genética , Preescolar , Niño , Inmunoglobulinas/sangre , Inmunoglobulinas/genética , Mutación , TransducinaRESUMEN
Achondroplasia (ACH) is a rare, autosomal dominant skeletal dysplasia characterized by short stature, characteristic facial configuration, and trident hands. Before vosoritide approval in Japan, patients with ACH could start growth hormone (GH) treatment at age 3 years. However, ACH and its treatment in young Japanese children have not been studied. This retrospective, longitudinal, medical records-based cohort study (before vosoritide approval) summarized symptoms, complications, monitoring, surgery/interventions, and height with/without GH in Japanese patients with ACH <5 years. Complications were observed in 89.2% of all 37 patients; 75.7% required surgery or intervention. All patients were monitored by magnetic resonance imaging; 73.0% had foramen magnum stenosis, while 54.1% had Achondroplasia Foramen Magnum Score 3 or 4. Of 28 GH-treated patients, 22 initiating at age 3 years were generally taller after 12 months versus 9 non-GH-treated patients. Mean annual growth velocity significantly increased from age 2 to 3 versus 3 to 4 years in GH-treated patients (4.37 vs. 7.23 cm/year; p = 0.0014), but not in non-GH-treated patients (4.94 vs. 4.20 cm/year). The mean height at age 4 years with/without GH was 83.6/79.8 cm. These results improve our understanding of young patients with ACH in Japan and confirm that early diagnosis of ACH and monitoring of complications help facilitate appropriate interventions.
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Acondroplasia , Humanos , Acondroplasia/tratamiento farmacológico , Acondroplasia/genética , Acondroplasia/patología , Masculino , Femenino , Estudios Retrospectivos , Preescolar , Japón/epidemiología , Lactante , Hormona de Crecimiento Humana/uso terapéutico , Resultado del Tratamiento , Niño , Estatura/efectos de los fármacos , Manejo de la Enfermedad , Registros Médicos , Imagen por Resonancia Magnética , Pueblos del Este de AsiaRESUMEN
INTRODUCTION: The testicular regression syndrome (TRS) is a form of differences of sex development (DSD) in which the testes differentiate and function during early embryonic development, but subsequently regress. The clinical phenotype of TRS often overlaps with that of partial gonadal dysgenesis (PGD). Previous studies have demonstrated a causal association between TRS/PGD and heterozygous missense variants of DHX37. METHODS: We enrolled 11 Japanese 46,XY individuals (from 10 families) with TRS/PGD who exhibited undetected or hypoplastic testes, Müllerian duct regression, and low serum testosterone or anti-Müllerian hormone levels. The subjects underwent targeted sequencing of 36 known causative genes for DSD, PCR-based Sanger sequencing of DHX37, or whole exome sequencing. RESULTS: Previously described pathogenic variants or novel nonsense variants (SRY, NR5A1, and DMRT1) were observed in four out of 10 families. Additionally, we identified two heterozygous rare variants of DHX37 in four families: a previously reported pathogenic variant (c.923G>A, p.Arg308Gln) in three and a novel likely pathogenic variant (c.1882A>C, p.Thr628Pro) in one. The external genitalia of patients with the DHX37 variants varied from female-type to male-type without micropenis. Eighty percent of Japanese patients with TRS/PGD had monogenic disorders including DHX37 variant being the most commonly identified (40%). The external or internal genital phenotype of TRS/PGD overlaps between DHX37 variant carriers and others. CONCLUSIONS: DHX37 variant is one of common genetic causes in Japanese patients with TRS/PGD without Müllerian derivatives. Genetic test is helpful in detecting DHX37-related TRS/PGD, because of the phenotypic diversity of the external genitalia in this disorder.
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CONTEXT: Adrenal crisis (AC) is a life-threatening complication that occurs during follow-up of patients with adrenal insufficiency (AI). No prospective study has thoroughly investigated AC in children with primary and secondary AI. OBJECTIVE: This work aimed to determine the incidence and risk factors for AC in patients with pediatric-onset AI. METHODS: This multicenter, prospective cohort study conducted in Japan enrolled patients diagnosed with AI at age ≤15 years. The incidence of AC was calculated as events per person-year (PY), and risk factors for AC were assessed using Poisson regression multivariable analysis. RESULTS: The study population comprised 349 patients (164 male, 185 female) with a total follow-up of 961 PY. The median age at enrollment was 14.3 years (interquartile range [IQR] 8.5-21.2 years), and the median follow-up was 2.8 years (IQR 2.2-3.3 years). Of these patients, 213 (61%) had primary AI and 136 (39%) had secondary AI. Forty-one AC events occurred in 31 patients during the study period. The calculated incidence of AC was 4.27 per 100 PY (95% CI, 3.15-5.75). Poisson regression analysis identified younger age at enrollment (relative risk [RR] 0.93; 95% CI, 0.89-0.97) and increased number of infections (RR 1.17; 95% CI, 1.07-1.27) as significant risk factors. Female sex (RR 0.99; 95% CI, 0.53-1.86), primary AI (RR 0.65; 95% CI, 0.30-1.41), or equivalent dosage of hydrocortisone per square meter of body area (RR 1.02; 95% CI, 0.96-1.08) was not a significant risk factor. CONCLUSION: A substantial proportion of patients with pediatric-onset AI experience AC. Younger age and an increased number of infections are independent risk factors for developing AC in these patients.
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Insuficiencia Suprarrenal , Humanos , Masculino , Femenino , Insuficiencia Suprarrenal/epidemiología , Insuficiencia Suprarrenal/etiología , Incidencia , Niño , Factores de Riesgo , Adolescente , Estudios Prospectivos , Japón/epidemiología , Adulto Joven , Preescolar , Estudios de Seguimiento , Edad de Inicio , HidrocortisonaRESUMEN
Hyperphosphatemic familial tumoral calcinosis (HFTC) is a rare, inherited autosomal recessive disorder caused by fibroblast growth factor-23 (FGF23), N-acetylgalactosaminyltransferase 3 (GALNT3), or Klotho (KL) gene variants. Here, we report the case of a Japanese boy who presented with a mass in his left elbow at the age of three. Laboratory test results of the patient revealed normocalcemia (10.3 mg/dL) and hyperphosphatemia (8.7 mg/dL); however, despite hyperphosphatemia, serum intact FGF23 level was low, renal tubular reabsorption of phosphate (TRP) level was inappropriately increased, and 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) level was inappropriately normal. Genetic analysis revealed maternal uniparental disomy (UPD) of chromosome 2, which included a novel GALNT3 variant (c.1780-1G>C). Reverse transcription-polymerase chain reaction (RT-PCR) analysis of GALNT3 mRNA confirmed that this variant resulted in the destruction of exon 11. We resected the mass when the patient was five years old, owing to its gradual enlargement. No relapse or new pathological lesions were observed four years after tumor resection. This is the first case report of a Japanese patient with HFTC associated with a novel GALNT3 variant, as well as the first case of HFTC caused by maternal UPD of chromosome 2 that includes the GALNT3 variant.
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Mutations in transport and Golgi organization 2 homolog (TANGO2) have recently been described as a cause of an autosomal recessive syndrome characterized by episodes of metabolic crisis associated with rhabdomyolysis, cardiac arrhythmias, and neurodegeneration. Herein, we report a case of a one-and-a-half-year-old Japanese girl, born to nonconsanguineous parents, who presented with metabolic crisis characterized by hypoglycemia with hypoketonemia, rhabdomyolysis, lactic acidosis, and prolonged corrected QT interval (QTc) at the age of 6 months. Acylcarnitine analysis during the episode of crisis showed prominent elevation of C14:1, suggesting very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. In addition, worsening rhabdomyolysis was observed after intravenous administration of L-carnitine. VLCAD deficiency was initially suspected; however, the enzyme activity in lymphocytes was only mildly decreased at the gene carrier level, and no mutation in the VLCAD gene (ADADVL) was detected. Subsequently, acylcarnitine analysis was nonspecific at 17-h fasting and almost normal during the stable phase. Eventually, a trio whole-exome sequencing revealed a compound heterozygous variant of two novel variants in the TANGO2 gene, a missense variant, and a deletion of exon 7. This is the first case of TANGO2 deficiency in Asians. Our case suggests that elevated C14:1 may be seen in severe metabolic crises and that the use of L-carnitine should be avoided during metabolic crises.
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Type 1 insulin-like growth factor receptor (IGF1R) plays an important role in normal fetal and postnatal growth. Over 30 pathogenic variants of IGF1R have been identified in patients with short stature. Yet, 20 years after the first report, a variety of phenotypes remain poorly defined. We analyzed the genetic and clinical data and responses to GH therapy in 11 patients using results from questionnaires. Eight of the 11 patients have already been reported in previous articles, and all of the identified mutations were heterozygous. The patients exhibited various phenotypes. At least two patients did not meet the criteria for GH treatment for small for gestational age (SGA) short stature, and two more patients showed lower serum IGF1 levels. Nine of the 11 patients had thin upper lips. Five patients with heterozygous IGF1R treated with GH exhibited similar height gains to those reported in previous Japanese studies on SGA short stature, which also led to extremely high serum IGF1 levels. Patients with short stature due to IGF1R mutations exhibit various phenotypes. Their presentation at diagnosis may be indistinguishable from common short stature. More specific clinical scoring that considers elevated IGF1 levels after GH treatment is needed to better detect IGF1R mutations.
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Complete androgen insensitivity syndrome (CAIS) is caused by mutations in the androgen receptor gene. Patients with this syndrome have a 46,XY karyotype, male gonads, and normal female external genitalia. While the pre-pubertal risk of developing gonadal tumors is low in these patients, it increases with age. Most gonadal tumors arise from germ cells; stromal cell tumors are uncommon. Herein, we report a CAIS patient with a feminizing Sertoli cell tumor. The patient presented at 8 yr of age with breast enlargement and growth acceleration, concomitant with elevated serum estradiol levels and suppressed serum gonadotropin levels; these findings were inconsistent with CAIS. The patient underwent gonadectomy at 10 yr of age, and histology demonstrated presence of a non-malignant Sertoli cell tumor in the right gonad. We conclude that this is the first reported case of CAIS with accelerated onset of puberty resulting from a Sertoli cell tumor.
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Background: Biochemically monitoring 21-hydroxylase deficiency (21-OHD) is challenging. Serum/blood 17-hydroxyprogesterone (17OHP) measurements are normally used for this purpose. Urinary pregnanetriol (PT), a urinary metabolite of 17OHP, may also be used. Based on auxological data, we previously reported that the optimal first morning PT value fell in the range of 2.2-3.3 mg/gCr (95% confidence interval of the mean) and 0.59-6.0 mg/gCr (10th - 90th percentile) for monitoring 21-OHD treatment. No report thus far has directly compared the first morning urinary PT value with the 17OHP value at various times during the day. Objective: To explore the correlation between the first morning urinary PT value before glucocorticoid administration and the serum/blood 17OHP value at three time points, namely, before and two and four hours after glucocorticoid administration. Design: This was a prospective study done at two children's hospitals. Methods: In total, 25 patients with 21-OHD aged 3-25 years were recruited. Their urinary PT levels and 17OHP levels were measured for three days within a total period of one week. The first morning PT value was collected on all three days. Dried blood spots and serum were used to measure 17OHP. Results: The range for the first morning PT value for all the samples (n=69) was 0.10-56.1 mg/gCr. A significant, positive correlation was found between the first morning PT and 17OHP values before medication (r=0.87, p<0.01), and weaker correlation was observed between the first morning PT and 17OHP values after medication. Conclusions: The first morning PT correlated more significantly with 17OHP before the morning medication. Measuring the first morning PT value may be more practical and useful for monitoring 21-OHD biochemically.
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Hiperplasia Suprarrenal Congénita , Pregnanotriol , 17-alfa-Hidroxiprogesterona/uso terapéutico , Adolescente , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Adulto , Niño , Preescolar , Humanos , Pregnanotriol/uso terapéutico , Pregnanotriol/orina , Estudios Prospectivos , Adulto JovenRESUMEN
CONTEXT: Lipoid congenital adrenal hyperplasia (LCAH) is caused by mutations in STAR. Classic (CLCAH) and nonclassic (NCLCAH) forms were reported as total and partial deficiencies, respectively, of adrenal and gonadal steroid hormones. The rarity of LCAH has precluded large-scale epidemiological and clinical investigations. OBJECTIVE: To determine the epidemiological and clinical characteristics of 2 forms of LCAH. DESIGN: A multicenter cross-sectional cohort study in Japan on December 1, 2017. PARTICIPANTS: Fifty-seven patients with LCAH (median age, 23.7 years; range, 0.0-47.5 years). MAIN OUTCOME MEASURES: Patient demographics, STAR genotype, Quigley grade, endocrinological and imaging data, treatment, and prognosis. RESULTS: Fifty-three and 4 patients fulfilled definite and probable diagnostic criteria for LCAH, respectively. When NCLCAH was defined as either Quigley grade 1 in XY karyotype, no episode of salt losing or requirement of fludrocortisone, or onset of primary adrenal insufficiency (PAI) at 1 year or older, patients were divided into groups of 43 patients with CLCAH (75.4%), 11 with NCLCAH (19.3%), and 3 with unclassified LCAH (5.3%). All of the patients with CLCAH and 7/11 NCLCAH (63.6%) were treated with fludrocortisone. CLCAH was diagnosed at a significantly younger age than NCLCAH (median, 0.0 vs 4.0 years). STAR-Arg272Cys or -Met225Thr was identified only in NCLCAH (8/11, 72.7%). CONCLUSIONS: We demonstrated the relative proportions and clinical and molecular characteristics of NCLCAH and CLCAH in Japan. These criteria for NCLCAH correspond to all previously published cases and our cases whose masculinization of the external genitalia, ability of mineralocorticoid production, and onset of PAI were described.
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Hiperplasia Suprarrenal Congénita/diagnóstico , Trastorno del Desarrollo Sexual 46,XY/diagnóstico , Fludrocortisona/uso terapéutico , Mineralocorticoides/uso terapéutico , Mutación , Fenotipo , Fosfoproteínas/genética , Adolescente , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Hiperplasia Suprarrenal Congénita/genética , Adulto , Niño , Preescolar , Estudios Transversales , Trastorno del Desarrollo Sexual 46,XY/tratamiento farmacológico , Trastorno del Desarrollo Sexual 46,XY/genética , Femenino , Humanos , Lactante , Recién Nacido , Japón , Persona de Mediana Edad , Pronóstico , Adulto JovenRESUMEN
BACKGROUND: There are no randomized controlled trials examining the effect of walking on childhood obesity. METHODS: A randomized controlled trial was conducted between August 2014 and April 2015 in Japan. Elementary school children aged 6 to 12 years with a percentage overweight (%OW) of ≥20% were recruited. One hundred and ninety children wanted to participate in the program, and all were accepted. After viewing a video that promoted physical activity through walking, participants were randomly assigned to three groups: walking (≥10 000 steps on school holidays), limiting screen time (<90 min on weekdays and <150 min on school holidays), and a control group (no intervention). The primary outcome was a decrease in %OW after 3 months' intervention. Per protocol analysis was performed using 156 participants who fulfilled the inclusion criteria of a %OW ≥20%. RESULTS: The mean %OW was 35 ± 7% before intervention. The mean reduction in %OW after intervention in the walking (n = 59), limiting ST (n = 46), and control (n = 51) groups were -4.06 ± 4.84, -1.97 ± 4.62, and -1.81 ± 3.64 percentage points, respectively. Reduction in %OW was significantly larger in the walking group than in the control group: adjusted mean difference, -2.18 percentage points (95% confidence interval, -3.85 to -0.52), P = 0.002. The intervention in children also had favorable effects on the lifestyles of their parents. The intention-to-treat analysis of all 190 participants showed comparable results. CONCLUSION: Promoting physical activity through walking on school holidays may be an additional strategy for treating elementary school children with obesity.
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Ejercicio Físico , Obesidad Infantil/terapia , Caminata , Índice de Masa Corporal , Niño , Femenino , Vacaciones y Feriados , Humanos , Japón , Estilo de Vida , Masculino , Sobrepeso/terapia , Padres , Instituciones Académicas , Tiempo de Pantalla , Resultado del TratamientoRESUMEN
BACKGROUND: Congenital hypogonadotropic hypogonadism (CHH) is classified as Kallmann syndrome (KS) with anosmia/hyposmia or normosmic (n)CHH. Here, we investigated the genetic causes and phenotype-genotype correlations in Japanese patients with CHH. METHODS: We enrolled 22 Japanese patients with CHH from 21 families (18 patients with KS and 4 with nCHH) and analyzed 27 genes implicated in CHH by next-generation and Sanger sequencing. RESULTS: We detected 12 potentially pathogenic mutations in 11 families, with three having a mutation in ANOS1 (X-linked recessive); three and four having a mutation in FGFR1 and CHD7, respectively (autosomal dominant); and one having two TACR3 mutations (autosomal recessive). Among four patients with KS carrying a CHD7 mutation, one had perceptive deafness and two had a cleft lip/palate. CONCLUSIONS: The frequency of CHH genes in the Japanese was compatible with previous reports, except that CHD7 mutations might be more common. Furthermore, partial phenotype-genotype correlations were demonstrated in our cohort.
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Hipogonadismo/diagnóstico , Síndrome de Kallmann/diagnóstico , Mutación , Adolescente , Niño , Preescolar , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Proteínas de la Matriz Extracelular/genética , Femenino , Humanos , Hipogonadismo/genética , Lactante , Síndrome de Kallmann/genética , Masculino , Proteínas del Tejido Nervioso/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Adulto JovenRESUMEN
The etiology of idiopathic short stature (ISS) and Leri-Weill dyschondrosteosis (LWD) in European patients is known to include SHOX mutations and copy-number variations (CNVs) involving SHOX and/or the highly evolutionarily conserved non-coding DNA elements (CNEs) flanking the gene. However, the frequency and types of SHOX abnormalities in non-European patients and the clinical importance of mutations in the CNEs remains to be clarified. Here, we performed systematic molecular analyses of SHOX for 328 Japanese patients with ISS or LWD. SHOX abnormalities accounted for 3.8% of ISS and 50% of LWD cases. CNVs around SHOX were identified in 16 cases, although the ~47 kb deletion frequently reported in European patients was absent in our cases. Probably damaging mutations and benign/silent substitutions were detected in four cases, respectively. Although CNE-linked substitutions were detected in 15 cases, most of them affected poorly conserved nucleotides and were shared by unaffected individuals. These results suggest that the frequency and mutation spectrum of SHOX abnormalities are comparable between Asian and European patients, with the exception of a European-specific downstream deletion. Furthermore, this study highlights the clinical importance and genetic heterogeneity of the SHOX-flanking CNVs, and indicates a limited clinical significance of point mutations in the CNEs.
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Enanismo/diagnóstico , Enanismo/genética , Estudios de Asociación Genética , Variación Genética , Trastornos del Crecimiento/diagnóstico , Trastornos del Crecimiento/genética , Proteínas de Homeodominio/genética , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Adolescente , Niño , Preescolar , Estudios de Cohortes , Variaciones en el Número de Copia de ADN , Femenino , Heterogeneidad Genética , Humanos , Lactante , Japón , Masculino , Mutación , Fenotipo , Análisis de Secuencia de ADN , Proteína de la Caja Homeótica de Baja Estatura , SíndromeRESUMEN
Selenocysteine (Sec) insertion sequence-binding protein 2 (SBP2) is essential for the biosynthesis of Sec-containing proteins, termed selenoproteins. Subjects with mutations in the SBP2 gene have decreased levels of several selenoproteins, resulting in a complex phenotype. Selenoproteins play a significant role in antioxidative defense, and deficiencies in these proteins can lead to increased oxidative stress. However, lipid peroxidation and the effects of antioxidants in subjects with SBP2 gene mutations have not been studied. In the present study, we evaluated the lipid peroxidation products in the blood of a subject (the proband) with mutations in the SBP2 gene. We found that the proband had higher levels of free radical-mediated lipid peroxidation products, such as 7ß-hydroxycholesterol, than the control subjects. Treatment of the proband with vitamin E (α-tocopherol acetate, 100 mg/day), a lipid-soluble antioxidant, for 2 years reduced lipid peroxidation product levels to those of control subjects. Withdrawal of vitamin E treatment for 7 months resulted in an increase in lipid peroxidation products. Collectively, these results clearly indicate that free radical-mediated oxidative stress is increased in the subject with SBP2 gene mutations and that vitamin E treatment effectively inhibits the generation of lipid peroxidation products.
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Antioxidantes/uso terapéutico , Peroxidación de Lípido/efectos de los fármacos , Proteínas de Unión al ARN/genética , Vitamina E/uso terapéutico , Adolescente , Antioxidantes/farmacología , Estudios de Casos y Controles , Niño , Femenino , Humanos , Recuento de Leucocitos , Masculino , Enfermedades Metabólicas/tratamiento farmacológico , Mutación Missense , Selenoproteínas/sangre , Vitamina E/farmacologíaRESUMEN
Pseudoautosomal region 1 (PAR1) contains SHOX, in addition to seven highly conserved non-coding DNA elements (CNEs) with cis-regulatory activity. Microdeletions involving SHOX exons 1-6a and/or the CNEs result in idiopathic short stature (ISS) and Leri-Weill dyschondrosteosis (LWD). Here, we report six rare copy-number variations (CNVs) in PAR1 identified through copy-number analyzes of 245 ISS/LWD patients and 15 unaffected individuals. The six CNVs consisted of three microduplications encompassing SHOX and some of the CNEs, two microduplications in the SHOX 3'-region affecting one or four of the downstream CNEs, and a microdeletion involving SHOX exon 6b and its neighboring CNE. The amplified DNA fragments of two SHOX-containing duplications were detected at chromosomal regions adjacent to the original positions. The breakpoints of a SHOX-containing duplication resided within Alu repeats. A microduplication encompassing four downstream CNEs was identified in an unaffected father-daughter pair, whereas the other five CNVs were detected in ISS patients. These results suggest that microduplications involving SHOX cause ISS by disrupting the cis-regulatory machinery of this gene and that at least some of microduplications in PAR1 arise from Alu-mediated non-allelic homologous recombination. The pathogenicity of other rare PAR1-linked CNVs, such as CNE-containing microduplications and exon 6b-flanking microdeletions, merits further investigation.
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Variaciones en el Número de Copia de ADN , Trastornos del Crecimiento/genética , Proteínas de Homeodominio/genética , Región de Flanqueo 3'/genética , Región de Flanqueo 5'/genética , Estudios de Casos y Controles , Niño , Preescolar , Enanismo/genética , Femenino , Duplicación de Gen , Frecuencia de los Genes , Humanos , Lactante , Masculino , Persona de Mediana Edad , Osteocondrodisplasias/genética , Eliminación de Secuencia , Proteína de la Caja Homeótica de Baja Estatura , Adulto JovenRESUMEN
OBJECTIVE: The type I insulin-like growth factor I receptor (IGF1R) plays an important role in growth. We aimed to evaluate the detailed mechanism underlying the effect of IGF1R on human growth. PATIENTS AND METHODS: We have performed sequence analysis of IGF1R in 55 patients with SGA short stature in Japan, since 2004, and identified novel heterozygous nonsense mutations in 2 patients: an 8-year-old Japanese boy (case 1), with a birthweight of 2228 g (-3·3 SDS) and height of 46 cm (-2·1 SDS), and a 3-year-old Japanese girl (case 2), with a birthweight of 2110 g (-3·0 SDS) and height of 44·3 cm (-2·8 SDS). Both patients had a short stature (-3·2 SDS, -3·1 SDS). We determined the protein expression of mutated IGF1R, assessed the effect of the endoplasmic reticulum-associated degradation (ERAD) pathway on mutated IGF1R, assessed the dominant-negative effect of IGF1R and performed quantitative RT-PCR analysis of IGF1R mRNA expression in whole blood cells. RESULTS: Two novel heterozygous nonsense mutations (case 1: p.Q1250X and case 2: p.W1249X) were identified. Although these mutations did not affect blood IGF1R mRNA levels, they significantly decreased the expression of IGF1R protein in transiently transfected cells. Treatment with the proteasome inhibitor MG132 showed significantly increased IGF1R protein. CONCLUSIONS: Heterozygous nonsense mutations affecting the C-terminal region (p.Q1250X, p.W1249X) of IGF1R decreased the expression of IGF1R through the ERAD pathway. Our study revealed the importance of the C-terminal region and the dosage of this receptor for growth.
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Codón sin Sentido/genética , Enanismo/genética , Degradación Asociada con el Retículo Endoplásmico/genética , Receptor IGF Tipo 1/genética , Estatura/genética , Estatura/fisiología , Niño , Preescolar , Femenino , Retardo del Crecimiento Fetal/genética , Heterocigoto , Humanos , Japón , Masculino , MutaciónRESUMEN
OBJECTIVES: Mutations in the dual oxidase 2 gene (DUOX2) is the most common genetic cause of congenital hypothyroidism (CH) in Japan. All previously described DUOX2 mutation-carrying families have followed autosomal recessive inheritance. We report a nonconsanguineous Japanese family harbouring biallelic DUOX2 mutations, which presented an apparently dominant inheritance of nonautoimmune hypothyroidism. DESIGN AND METHODS: The proband and her two sisters had been diagnosed as having CH on newborn screening and were treated with levothyroxine. Their mother had subclinical hypothyroidism. We sequenced DUOX2 in the proband and her family members. Pathogenicity of the identified novel mutation (p.Y1347C) was verified in vitro. RESULTS: We found that the proband and her sisters were compound heterozygous for a novel DUOX2 mutation p.Y1347C and a previously reported functional variant p.H678R. Unexpectedly, we found that the mother was homozygous for p.H678R. Expression experiments showed that the p.Y1347C mutant had reduced H2 O2 -producing activity, although there was no significant difference in the level of protein expression or localization, between wild type and p.Y1347C. CONCLUSIONS: We report a DUOX2 mutation-carrying pedigree presenting pseudodominant inheritance of nonautoimmune hypothyroidism. We speculate that the relatively high frequency of DUOX2 mutations could lead to pseudodominant inheritance in Japan.
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Hipotiroidismo Congénito/genética , Genes Dominantes , Patrón de Herencia/genética , Mutación Missense , NADPH Oxidasas/genética , Alelos , Hipotiroidismo Congénito/metabolismo , Análisis Mutacional de ADN , Oxidasas Duales , Salud de la Familia , Femenino , Genotipo , Humanos , Immunoblotting , Masculino , Microscopía Fluorescente , NADPH Oxidasas/metabolismo , LinajeRESUMEN
OBJECTIVE: Arboleda et al. have recently shown that IMAGe (intra-uterine growth restriction, metaphyseal dysplasia, adrenal hypoplasia congenita and genital abnormalities) syndrome is caused by gain-of-function mutations of maternally expressed gene CDKN1C on chromosome 11p15.5. However, there is no other report describing clinical findings in patients with molecularly studied IMAGe syndrome. Here, we report clinical and molecular findings in Japanese patients. PATIENTS: We studied a 46,XX patient aged 8·5 years (case 1) and two 46,XY patients aged 16·5 and 15·0 years (cases 2 and 3). RESULTS: Clinical studies revealed not only IMAGe syndrome-compatible phenotypes in cases 1-3, but also hitherto undescribed findings including relative macrocephaly and apparently normal pituitary-gonadal endocrine function in cases 1-3, familial glucocorticoid deficiency (FGD)-like adrenal phenotype and the history of oligohydramnios in case 2, and arachnodactyly in case 3. Sequence analysis of CDKN1C, pyrosequencing-based methylation analysis of KvDMR1 and high-density oligonucleotide array comparative genome hybridization analysis for chromosome 11p15.5 were performed, showing an identical de novo and maternally inherited CDKN1C gain-of-function mutation (p.Asp274Asn) in cases 1 and 2, respectively, and no demonstrable abnormality in case 3. CONCLUSIONS: The results of cases 1 and 2 with CDKN1C mutation would argue the following: [1] relative macrocephaly is consistent with maternal expression of CDKN1C in most tissues and biparental expression of CDKN1C in the foetal brain; [2] FGD-like phenotype can result from CDKN1C mutation; and [3] genital abnormalities may primarily be ascribed to placental dysfunction. Furthermore, lack of CDKN1C mutation in case 3 implies genetic heterogeneity in IMAGe syndrome.
Asunto(s)
Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/genética , Retardo del Crecimiento Fetal/diagnóstico , Retardo del Crecimiento Fetal/genética , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Anomalías Urogenitales/diagnóstico , Anomalías Urogenitales/genética , Adolescente , Niño , Cromosomas Humanos Par 11 , Hibridación Genómica Comparativa , Inhibidor p57 de las Quinasas Dependientes de la Ciclina/genética , Metilación de ADN , Exones , Femenino , Humanos , Japón , Cariotipificación , Masculino , Mutación , FenotipoRESUMEN
We performed a physical examination and ultrasonography of the thyroid gland in 24 patients who had received hematopoietic stem cell transplantation with a total-body irradiation (TBI)-containing regimen during childhood. When ultrasonography revealed thyroid nodules larger than 1 cm in diameter, fine-needle aspiration biopsies were performed. Of 5 patients with palpable masses and thyroid nodules larger than 1 cm, adenomatous goiter was diagnosed in 4 cases and thyroid cancer in 1. Of the remaining 19 patients in whom no palpable mass was detected in the physical examination, 5 had thyroid nodules (including 1 adenomatous goiter), 6 had cystic lesions, and 8 exhibited no abnormalities on ultrasonography. No significant differences in sex, age at transplantation, interval between transplantation and evaluation, primary disease, preconditioning regimen, status at transplantation, stem cell source, chronic graft-versus-host disease, hypogonadism, or hypothyroidism were observed between patients with and without nodules. Individuals who received hematopoietic stem cell transplantation with a TBI-containing regimen are at risk of secondary thyroid cancer due to radiotherapy and require regular clinical evaluations of the thyroid gland by palpation, and ultrasonography should be incorporated into these checkups.
Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Neoplasias Inducidas por Radiación/patología , Neoplasias de la Tiroides/etiología , Irradiación Corporal Total/efectos adversos , Adolescente , Biopsia con Aguja Fina/métodos , Niño , Preescolar , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Lactante , Masculino , Neoplasias de la Tiroides/patologíaRESUMEN
In many countries, methimazole (MMI) therapy is the first-line treatment in children with Graves' disease (GD). The rate of side effects of antithyroid drugs (ATDs) in children has been reported to range between 6% and 35%. Of these side effects, polyarthritis is uncommon but serious, and can also develop as a part of the antineutrophil cytoplasmic antibody-associated vasculitis that is induced by ATDs. Here, we describe two GD girl patients aged 15 years and 11 years who developed polyarthritis. The onset of polyarthritis in these patients was 24 days and 28 days after the initiation of MMI therapy, respectively. MMI was suspected of causing the polyarthritis in the two patients and was withdrawn. The symptoms of polyarthritis disappeared rapidly following cessation of treatment. Subsequently, one patient was treated with 131I therapy and the other patient was subjected to thyroidectomy. Although it rarely occurs in pediatric GD patients, severe polyarthritis is a serious side effect of MMI and is an indication for prompt cessation of treatment.