Genetic analysis of a child with Meier-Gorlin syndrome due to a variant of ORC6 gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze the genetic characteristics of a child with Meier-Gorlin syndrome (MGS) due to a homozygous variant of the ORC6 gene.@*METHODS@#A child who was admitted to the Children's Hospital Affiliated to Soochow University on March 25, 2019 due to growth retardation was selected as the study subject. Clinical data of the child was collected. Whole exome sequencing was carried out for the child. Candidate variant was validated by Sanger sequencing and bioinformatic analysis.@*RESULTS@#The child, a 8-year-and-3-month-old male, has featured short stature, small ears, bilateral cryptorchidism and patellar dysplasia. His parents were of first cousins. The child was found to harbor a homozygous c.712A>T (p.K238*) missense variant of the ORC6 gene, which may lead to premature termination of protein translation. Sanger sequencing confirmed that both of his parents were heterozygous carriers. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was classified as pathogenic (PVS1_Moderate+PM2_Supporting+PM3+PP3+PP4).@*CONCLUSION@#The homozygous c.712A>T (p.K238*) variant probably underlay the MGS in this child.

Helsmoortel-Van der Aa syndrome due to hotspot mutation of ADNP gene and a literature review / 中华医学遗传学杂志

OBJECTIVE@#To summarize the clinical features and biological characteristics of Helsmoortel Van der Aa syndrome (HVDAS) due to hotspot mutations of the ADNP gene in order to facilitate early diagnosis.@*METHODS@#Clinical data and result of genetic testing for a girl with HVDAS due to hotspot mutation of the ADNP gene was summarized. Related literature was also reviewed.@*RESULTS@#The patient, a 2-year-old girl, had presented with growth retardation, facial dysmorphism, psychomotor and language delay and recurrent respiratory infections. Whole exome sequencing revealed that she has harbored a heterozygous c.2496_2499delTAAA (p.Asn832Lysfs*81) variant of the ADNP gene, which was not found in either of her parents.@*CONCLUSION@#Although the typical features of the HVDAS have included intellectual disability and autism spectrum disorders, growth retardation and premature primary tooth eruption may also be present. In addition, the phenotypic difference among individuals carrying hot spot variants of the ADNP gene was not prominent.

Analysis of gene variation and clinical characteristics of Wiedemann-Steiner syndrome / 中华儿科杂志

Objective: To summarize and analyze the clinical characteristics and gene mutations of 6 patients with Wiedemann-Steiner syndrome (WDSTS). Methods: To review and analyze the clinical data, including general conditions, clinical manifestations, growth hormone, cranial or pituitary gland magnetic resonance imaging (MRI),gene results and other data, 6 cases with WDSTS admitted to the Department of Endocrinology, Genetics and Metabolism of Jiangxi Provincial Children's Hospital and the Department of Child Care of Pingxiang Maternity and Child Care from April 2017 to February 2021 were recruited. Results: Of the 6 patients, 2 were male and 4 were female. The age of the first visit ranged from 1.0 to 11.2 years. All the 6 children presented with growth retardation and mental retardation and they all had typical facial dysmorphism and hypertrichosis (mainly on the back and limbs). Among them, case 5 had a growth hormone deficiency, and case 2 and 4 had abnormalities revealed by cranial MRI. Variations in KMT2A gene were identified in these 6 patients: c.10900+2T>C,c.10837C>T(p.Gln3613*), c.4332G>A(p.E1444E), c.2508dupC(p.W838Lfs*9), c.11695_11696delinsT(p.T3899Sfs*73), c.9915dupA (p.P3306Tfs*22).Among these variations, c.4332G>A, c.11695_11696delinsT and c.9915dupA were novel mutations. Therefore, the final diagnosis of these patients was WDSTS. Conclusions: Patients presented with short stature and mental retardation, typical facial dysmorphism and hypertrichosis should be considered WDSTS. Whole-exome sequencing plays an important role in disease diagnosis and genetic counseling.

Update on new GH-IGF axis genetic defects

ABSTRACT The somatotropic axis is the main hormonal regulator of growth. Growth hormone (GH), also known as somatotropin, and insulin-like growth factor 1 (IGF-1) are the key components of the somatotropic axis. This axis has been studied for a long time and the knowledge of how some molecules could promote or impair hormones production and action has been growing over the last decade. The enhancement of large-scale sequencing techniques has expanded the spectrum of known genes and several other candidate genes that could affect the GH-IGF1-bone pathway. To date, defects in more than forty genes were associated with an impairment of the somatotropic axis. These defects can affect from the secretion of GH to the bioavailability and action of IGF-1. Affected patients present a large heterogeneous group of conditions associated with growth retardation. In this review, we focus on the description of the GH-IGF axis genetic defects reported in the last decade. Arch Endocrinol Metab. 2019;63(6):608-17

Genetic causes of isolated short stature

ABSTRACT Short stature is a common feature, and frequently remains without a specific diagnosis after conventional clinical and laboratorial evaluation. Longitudinal growth is mainly determined by genetic factors, and hundreds of common variants have been associated to height variability among healthy individuals. Although isolated short stature may be caused by the combination of variants, with a deleterious impact on the growth of individuals with polygenic inheritance, recent studies have pointed out some monogenic defects as the cause of the growth disorder observed in nonsyndromic children. The majority of these defects are in genes related to the growth plate cartilage and in the growth hormone (GH) - insulin-like growth factor 1 (IGF-1) axis. Affected patients usually present the mildest spectrum of some forms of skeletal dysplasia, or subtle abnormalities of laboratory tests, suggesting hormonal resistance or insensibility. The lack of specific characteristics, however, does not allow formulation of a definitive diagnosis without the use of broad genetic studies. Thus, molecular genetic studies including panels of genes or exome analysis will become essential in investigating and identifying the causes of isolated short stature in children, with a crucial impact on treatment and follow-up.

Variações no número de cópias cromossômicas submicroscópicas como causa de baixa estatura de início pré-natal / Submicroscopic chromosomal copy number variants as a cause of prenatal onset short stature

A pesquisa de variações no número de cópias (CNVs; copy number variants) cromossômicas tem revelado o importante papel destas alterações genômicas na diversidade populacional e na etiologia de doenças humanas. O modelo de associação de CNVs a doenças envolve deleções e/ou duplicações individualmente raras, mas com segmentos cromossômicos de tamanhos relevantes. Os pacientes com baixa estatura de início pré-natal constituem um grupo heterogêneo com quadros clínicos complexos frequentemente resultantes de alterações genéticas, que, desde o período intrauterino, perturbam os mecanismos e vias de desenvolvimento e crescimento fetais. Assim sendo, aventamos a hipótese de que CNVs raras possam estar entre as causas genéticas de baixa estatura de início prénatal. Para tanto, nosso estudo visou avaliar a presença de deleções ou duplicações submicroscópicas em um grupo selecionado de pacientes nascidos pequenos para idade gestacional (PIG) com baixa estatura persistente sem causa definida. Foram avaliados 51 pacientes nascidos PIG com baixa estatura persistente após o 4º ano de vida que apresentavam dismorfismos, atraso de desenvolvimento neuropsicomotor (DNPM) ou deficiência intelectual, porém sem caracterizar síndromes conhecidas e com cariótipo normal. Amostras de DNA dos pacientes foram submetidas à hibridização genômica comparativa por microarray (aCGH; array comparative genomic hybridization) baseada em oligonucleotídeos na plataforma 60K. Os achados foram comparados com CNVs descritas em bancos de dados de controles normais. Foram identificadas 18 CNVs, ausentes em controles saudáveis, em 17 dos 51 pacientes (33%). As alterações foram avaliadas para classificação de sua patogenicidade de acordo com os seguintes critérios: 1) padrão de herança e segregação familiar; 2) sobreposição a coordenadas genômicas de síndromes conhecidas; 3) sobreposição a CNVs patogênicas descritas em banco de dados; 4) e conteúdo gênico. Quatro CNVs, encontradas em 3 pacientes, foram...

Analysis of chromosomic copy number variants (CNVs) have demonstrated the important role of these genomic imbalances in population diversity and human disease. The model of CNV disease association involves deletions and/or duplications that are individually rare but encompass chromosomal segments of relevant size. Prenatal onset short stature patients constitute a complex group characterized by clinical heterogeneity. The causes of prenatal growth impairment frequently involve genetic changes that disturb the mechanisms and the pathways of fetal growth and development. Thus, we hipothesized that rare CNVs might contribute to the genetic etiology of prenatal onset short stature. In order to evaluate this assumption, our study analyzed the presence of submicroscopic deletions and/or duplications in a selected group of patients born small for gestational age with persistent short stature but without a recognized cause. A total of 51 patients with prenatal and postnatal growth retardation associated with dysmorphic features, developmental delay and/or intellectual disability, but without criteria for known syndromes, were selected. All patients had normal G-banded karyotyping. Array-based comparative genomic hybridization (aCGH) in a whole-genome 60K platform was performed using DNA obtained from all patients. Detected CNVs were compared with CNV data from healthy controls individuals, excluding common copy number polymorphisms. In 17 of the 51 patients screened (33%), 18 rare CNVs were identified. The pathogenicity of CNVs was assessed by considering the following criteria: inheritance and familial segregation; overlap with genomic coordinates for a known genomic imbalance syndrome; overlap with CNVs previously identified in other patients with prenatal onset short stature; and gene content. Four distinct CNVs, found in three patients, were classified as pathogenic: 1) del 22q11.21; 2) dup 10q26.2-26.3 and del 10q26.3; and 3) del 4q28.2-q31.21. Five CNVs, found...

Molecular characterization in a case of isolated growth hormone deficiency and further prenatal diagnosis of an unborn sibling.

Familial isolated growth hormone deficiency (GHD) type 1 is characterized by an autosomal recessive pattern of inheritance with varying degrees of phenotypic severity. We report a proband, with isolated GHD (IGHD) with very early growth arrest and undetectable levels of GH. Homozygous complete deletion of the GH1 gene was identified by real‑time/quantitative polymerase chain reaction (RT/q‑PCR) and confirmed by an independent molecular genetic method; the multiplex ligation‑dependent probe amplification (MLPA) technique. Prenatal diagnosis was offered for the subsequent pregnancy in the mother of our proband. Identical heterozygous deletion of the GH1 gene was detected in both parents. The fetus had a similar homozygous deletion of the GH1 gene. We thus report a unique case with a confirmed mutation in GH1 gene in the proband followed by prenatal detection of the same mutation in the amniotic fluid which to our knowledge hitherto has not been documented from India.

Hypoparathyroidism-retardation-dysmorphism syndrome.

Congenital hypoparathyroidism, growth retardation and facial dysmorphism is a rare autosomal recessive disorder seen among children born to consanguineous couple of Arab ethnicity. This syndrome is commonly known as Sanjad- Sakati or hypoparathyroidism‑retardation‑dysmorphism syndrome (HRD). We report 13‑year‑old Hindu boy with hypoparathyroidism, tetany, facial dysmorphism and developmental delay, compatible with HRD syndrome.

Mutational analysis of TAC3 and TACR3 genes in patients with idiopathic central pubertal disorders / Análise de mutações nos genes TAC3 e TACR3 em pacientes com distúrbios puberais centrais idiopáticos

OBJECTIVE: To investigate the presence of variants in the TAC3 and TACR3 genes, which encode NKB and its receptor (NK3R), respectively, in a large cohort of patients with idiopathic central pubertal disorders. SUBJECTS AND METHODS: Two hundred and thirty seven patients were studied: 114 with central precocious puberty (CPP), 73 with normosmic isolated hypogonadotropic hypogonadism (IHH), and 50 with constitutional delay of growth and puberty (CDGP). The control group consisted of 150 Brazilian individuals with normal pubertal development. Genomic DNA was extracted from peripheral blood and the entire coding region of both TAC3 and TACR3 genes were amplified and automatically sequenced. RESULTS: We identified one variant (p.A63P) in NKB and four variants, p.G18D, p.L58L (c.172C>T), p.W275* and p.A449S in NK3R, which were absent in the control group. The p.A63P variant was identified in a girl with CPP, and p.A449S in a girl with CDGP. The known p.G18D, p.L58L, and p.W275* variants were identified in three unrelated males with normosmic IHH. CONCLUSION: Rare variants in the TAC3 and TACR3 genes were identified in patients with central pubertal disorders. Loss-of-function variants of TACR3 were associated with the normosmic IHH phenotype. Arq Bras Endocrinol Metab. 2012;56(9):646-52.

OBJETIVO: Investigar a presença de variantes nos genes TAC3 e TACR3, os quais codificam a NKB e seu receptor (NK3R), respectivamente, em uma coorte de pacientes com distúrbios puberais centrais idiopáticos. SUJEITOS E MÉTODOS: Duzentos e trinta e sete pacientes foram estudados: 114 com puberdade precoce central (PPC), 73 com hipogonadismo hipogonadotrófico isolado normósmico (HHI) e 50 com retardo constitucional do crescimento e desenvolvimento (RCCD). O grupo controle consistiu de 150 indivíduos brasileiros que apresentaram desenvolvimento puberal normal. O DNA genômico foi extraído de sangue periférico, e as regiões codificadoras dos genes TAC3 e TACR3 foram amplificadas e sequenciadas automaticamente. RESULTADOS: Uma variante (p.A63P) foi identificada na NKB, e quatro variantes, p.G18D, p.L58L (c.172C>T), p.W275X e p.A449S, foram identificadas no NK3R, as quais foram ausentes no grupo controle. A variante p.A63P foi identificada em uma menina com PPC, e a variante p.A449S, em uma menina com RCCD. As variantes previamente descritas, p.G18D, p.L58L e p.W275X, foram identificadas em três indivíduos com HHI normósmico do sexo masculino não relacionados. CONCLUSÃO: Variantes raras nos genes TAC3 e TACR3 foram identificadas em pacientes com distúrbios puberais centrais idiopáticos. Mutações de perda de função no gene TACR3 foram associadas com o fenótipo de HHI normósmico. Arq Bras Endocrinol Metab. 2012;56(9):646-52.

Apolipoprotein E4 influences growth and cognitive responses to micronutrient supplementation in shantytown children from northeast Brazil

OBJECTIVE: Apolipoprotein E4 may benefit children during early periods of life when the body is challenged by infection and nutritional decline. We examined whether apolipoprotein E4 affects intestinal barrier function, improving short-term growth and long-term cognitive outcomes in Brazilian shantytown children. METHODS: A total of 213 Brazilian shantytown children with below-median height-for-age z-scores (HAZ) received 200,000 IU of retinol (every four months), zinc (40 mg twice weekly), or both for one year, with half of each group receiving glutamine supplementation for 10 days. Height-for-age z-scores, weight-for-age z-scores, weight-forheight z-scores, and lactulose:mannitol ratios were assessed during the initial four months of treatment. An average of four years (range 1.4-6.6) later, the children underwent cognitive testing to evaluate non-verbal intelligence, coding, verbal fluency, verbal learning, and delayed verbal learning. Apolipoprotein E4 carriage was determined by PCR analysis for 144 children. RESULTS: Thirty-seven children were apolipoprotein E4(+), with an allele frequency of 13.9 percent. Significant associations were found for vitamin A and glutamine with intestinal barrier function. Apolipoprotein E4(+) children receiving glutamine presented significant positive Pearson correlations between the change in height-for-age z-scores over four months and delayed verbal learning, along with correlated changes over the same period in weight-for-age z-scores and weight-for-height z-scores associated with non-verbal intelligence quotients. There was a significant correlation between vitamin A supplementation of apolipoprotein E4(+) children and improved delta lactulose/mannitol. Apolipoprotein E4(-) children, regardless of intervention, exhibited negative Pearson correlations between the change in lactulose-to-mannitol ratio over four months and verbal learning and non-verbal intelligence. CONCLUSIONS: During development, apolipoprotein E4 may function concomitantly with gut-tropic nutrients to benefit immediate nutritional status, which can translate into better long-term cognitive outcomes.

Avaliação do padrão de crescimento na síndrome de Noonan em pacientes com mutações identificadas nos genes PTPN11, SOS1, RAF1 e KRAS / Growth pattern of patients with Noonan syndrome with identified mutations in PTPN11, SOS1, RAF1 e KRAS genes

A Síndrome de Noonan (SN) é caracterizada por baixa estatura proporcionada de início pós-natal, dismorfismos faciais, cardiopatia congênita e deformidade torácica. A frequência da SN é estimada entre 1:1000 e 1:2500 nascidos vivos, com distribuição semelhante em ambos os sexos. A herança é autossômica dominante com penetrância completa, porém a maioria dos casos é esporádica. Até o momento, mutações em genes da via RAS-MAPK (PTPN11, KRAS, SOS1, RAF1, MEK1, NRAS e SHOC2) foram identificadas em aproximadamente 70% dos pacientes. Uma das principais características fenotípicas da SN é a baixa estatura pós-natal, embora o mecanismo fisiopatológico do déficit de crescimento nesta síndrome ainda não esteja totalmente esclarecido. Estudos que avaliaram o padrão de crescimento linear em crianças com SN foram realizados anteriormente ao conhecimento do diagnóstico molecular dessa síndrome. No presente estudo, avaliamos a frequência de mutação nos genes PTPN11, SOS1, RAF1 e KRAS em 152 pacientes com SN e o padrão de crescimento linear (altura) e ponderal [índice de massa corpórea (IMC)] dos pacientes com mutação identificada. No total, mutações nos genes relacionados foram encontradas em 99 pacientes (65%) do nosso estudo, com predominância do gene PTPN11 (47%), seguido do SOS1 (9%), RAF1 (7%) e KRAS (3%). Foram construídas curvas específicas para SN de Altura e IMC para idade e sexo utilizando o método LMS. Os pacientes com SN apresentaram crescimento pré-natal preservado, porém o comprometimento do crescimento pós-natal foi observado desde o primeiro ano de vida, atingindo uma altura final de -2,5 e -2,2 desvios-padrão da média para população brasileira em homens e mulheres, respectivamente. O prejuízo da altura foi maior nos pacientes com mutação no gene RAF1 em comparação com os genes PTPN11 e SOS1. O IMC dos pacientes com SN apresentou queda de 1 desvio-padrão em relação à média da população brasileira normal. O comprometimento do IMC foi menor...

Noonan Syndrome (NS) is characterized by distinctive facial features, short stature and congenital heart defects. The estimated prevalence is 1:1000 to 1:2500 live births, affecting equally both sexes. It is an autosomal dominant disorder with complete penetrance, but most cases are sporadic. To date, mutations in the RAS/MAPK pathway genes (PTPN11, KRAS, SOS1, RAF1, MEK1, NRAS and SHOC2) were identified in approximately 70% of patients. One of the cardinal signs of NS is proportional postnatal short stature although the physiopathological mechanism of growth impairment remains unclear. The current knowledge about the natural history of growth associated with NS was described before molecular diagnosis era. In this study, we performed PTPN11, SOS1, RAF1, and KRAS mutation analysis in a cohort of 152 NS patients and studied the natural linear (height) and ponderal growth [body mass index (BMI)] of NS patients with related mutations. Mutations in NS-causative genes were found in 99 patients (65%) of our cohort. The most common mutated gene was PTPN11 (47%), followed by SOS1 (9%), RAF1 (7%) and KRAS (3%). Sex-specific percentile curves for height and BMI were constructed using the LMS method. NS patients had birth weight and length within normal ranges but the postnatal growth impairment was observed during the first year of life, reaching a final height of -2.3 and -2.2 standard deviations from the mean for Brazilian healthy men and women, respectively. Postnatal growth impairment was higher in RAF1 mutation patients than in patients with SOS1 and PTPN11 mutations. BMI values in NS patients were lower in comparison with normal Brazilian population. BMI values were higher in patients with RAF1 mutations than in patients with other genotypes. Patients with mutations in PTPN11 and SOS1 genes were more likely to have pulmonary valve stenosis, whereas hypertrophic cardiomyopathy was more common in patients with mutations in the gene RAF1...

Displasia espóndilo-epifisiaria asociada a cráneo-sinostosis, cataratas, paladar hendido y retardo mental: Reporte de un caso / Spondylo-epiphyseal dysplasia associated with craniosynostosis, cleft palate and mental retardation: A case report

Las displasias esqueléticas son un grupo muy heterogéneo de trastornos que se caracterizan por una alteración en la organización del tejido óseo, lo que causa una distorsión en su patrón de crecimiento y desarrollo. En 1998, se descibió el caso de cuatro hermanos japoneses, tres varones y una hembra que presentaban una displasia espóndilo-epifisiaria, no descrita anteriormente, asociada con cráneo-sinostosis, cataratas, paladar hendido y retardo mental de diferente grado. Se planteó una probable herencia autosómica recesiva, debido a que las alteraciones afectaban a ambos sexos y los padres eran fenotípicamente sanos, aunque con discreto retardo mental; sin embargo, no fue posible descartar un mosaicismo germinal. El caso que se presenta, trata de un paciente con signos clínicos y radiológicos que coinciden con los previamente descritos. Es producto de padres consanguíneos en la segunda generación, lo cual se sumaría a la presunción ya postulada, de una probable mutación de herencia autosómica recesiva. La presente comunicación, representa el segundo reporte en la literatura, del quinto caso descrito y el segundo grupo familiar con la afección mencionada.

Skeletal dysplasias are a heterogeneous group of disorders characterized by an alteration of the organization of osseous tissue causing a distortion on the growth and development pattern of bones. In 1998, four Japanese sibs were described by the first time, three males and one female who presented a previously undescribed spondylo-epiphyseal dysplasia associated with craniosynostosis, cataracts, cleft palate and different grades of mental retardation. A probable autosomic recessive inheritance was suggested, but a germinal mosaicism could not be discarded. This is a case report of a patient with clinical and radiological findings similar to the ones previously described, born to second degree consanguineous parents. This supports the postulated presumption of a mutation with an autosomic recesive inheritance. The present comunication represents the fifth case reported in the literature and the second familiar group affected.

Síndrome de Dubowitz: a propósito de un caso / Dubowitz Syndrome: a case presentation

El Síndrome de Dubowitz es un raro trastorno autosómico recesivo caracterizado por retraso del crecimiento pre y postnatal, rasgos dismórficos faciales, ptosis palpebral, retraso del desarrollo psicomotor, del lenguaje y conducta hiperactiva, discrepancia de miembros inferiores, hiperpigmentación de la piel, eczema, microcefalia, sindactilia, clinodactilia de los quintos dedos, hiperelasticidad de articulaciones, cifoescoliosis y otras anomalías como múltiples caries dentales, hipospadias, cirptorquidia, inmunodeficiencia y neoplasias. El propósito de este reporte de caso es describir un paciente pediátrico con este síndrome, especialmente asociado a infecciones respiratorias a repetición y crisis epilépticas recurrentes.

The Dubowitz Syndrome is a rare recessive autosomic disorder characterized by pre-and postnatal growth retardation, face dismorfic characteristics, palpebral ptosis, delay of psychomotor development, language and hyperactive conduct, discrepancy of inferior members, hyper pigmentation of the skin, eczematous, microcephaly, syndactylism, clinodactily of the fifth fingers, hyperelasticity of joints, kyphoscoliosis and other anomalies like multiple dental caries, hypospadias, cirptorquidia, immunodeficiency and neoplasias. The intention of this case report is to describe a pediatric patient with this syndrome, especially associated to repetitive respiratory infections and epileptic appellants’ crises.

Avances en el diagnóstico de las alteraciones del eje somatotrófico que causan retardo del crecimiento / An update on the diagnosis of growth hormone axis disturbances that cause stunting

Human growth is a complex process regulated by several genes, most of which are unknown. Recently, our knowledge regarding the etiology of genetically determined causes of short stature has greatly increased, so molecular analysis is becoming essential for the diagnosis of growth retardation. The advances in our understanding of the molecular mechanisms involved in the function of the somatotrophic axis have resulted in a dramatic enhancement of our ability to diagnose and treat growth disorders. We hope that in the next few years improved methods for identifying specific abnormalities which cause short stature will expand our ability to diagnose other causes of growth retardation, and reduce the proportion of patients with "idiopathic" short stature.

Características cranianas, faciais e dentárias em indivíduos acondroplásicos / Craniofacial and dental features in achondroplastic individuals

A acondroplasia é a forma mais comum de nanismo por encurtamento dos membros. É uma síndrome hereditária de caráter autossômico dominante, que também pode ser causada por novas mutações genéticas. A formação óssea endocondral é defeituosa e leva a alterações craniofaciais e dentárias típicas. Os pacientes acometidos apresentam macroencefalia, calota craniana volumosa, base do crânio encurtada, nariz em sela e estreitamento de vias aéreas, além de retrognatia maxilar, discrepância entre arcos dentários e maloclusões acentuadas. O presente artigo tem como objetivo apresentar as características craniofaciais e dentárias de pacientes acondroplásicos, por meio de revisão de literatura.

Achondroplasia is the most common hereditary form of dwarfism. The syndrome is inherited in an autosomal dominant manner but it can also be a result of a new gene mutation. The defective endochondral bone formation causes typical craniofacial and dental features such as enlarged calvarium, short posterior cranial base, depressed nasal bridge, short upper airway, retrognathic maxilla and malocclusion. The aim of the present article is to introduce the craniofacial and dental features of achondroplastic patients, by reviewing the literature.

Isocromosoma 18q en mosaico: caso clínico / Mosaic Isochromosome 18q: case-report

Background: The Isochromosome 18q and chromosome 18 short arm deletion (18p-) constitute structural anomalies that are reported with certain frequency in the literature. However, the association of both abnormalities in a patient is very uncommon. Objective: Description of a clinical case of Isochromosome 18 with emphasys in the few phenotypic manifestations. Case-report: Female infant 18 months-old, with short stature, minor dysmorphic features and a slight psychomotor developmental delay, whose chromosomal study in peripheral blood showed a chromosomal mosaicism with two cell lines: chromosome 18 long arm isochromosome and deletion of chromosome 18 short arm. The chromosomal analysis of both parents did not show numerical neither morphological alterations. Discussion: This case illustrates the importance of requesting a karyotype in patients with small stature, dysmorphic features and/or malformations. The patient clinical features are compared with other similar cases described in the literature. The coexistence of both structural abnormalities (mosaicism) is extremely uncommon.

Introducción: El Isocromoma 18q y la deleción del brazo corto del cromosoma 18 (18p-), son anomalías estructurales que se reportan con cierta frecuencia en la literatura. Sin embargo, la asociación de ambas alteraciones en una misma paciente es muy infrecuente. Objetivo: Descripción de un caso clínico de Isocromosoma 18 con énfasis en la escasas manifestaciones fenotípicas. Caso Clínico: Lactante femenino de 18 meses de edad portador de talla baja, dismorfias menores y un leve retraso del desarrollo sicomotor, cuyo estudio cromosómico en sangre periférica mostró un mosaico compuesto por un isocromosoma del brazo largo del cromosoma 18 y otro cromosoma 18 con deleción del brazo p. El análisis cromosómico de ambos padres no mostró alteraciones numéricas ni morfológicas. Discusión: Este caso ilustra la importancia de solicitar un cariograma en pacientes con talla baja, dismorfias y/o malformaciones. Se describen las malformaciones encontradas y se compara con otros casos similares descritos en la literatura. La alteración estructural en mosaico reportada es sumamente infrecuente.

Estudo do gene do fator de crescimento insulina-símile 1 (IGF1) e de receptor (IGF1R) em crianças nascidas pequenas para a idade gestacional / Study of insuline-like growth factor gene (IGF1) and its receptor in children born small for gestational age

Crianças nascidas pequenas para a idade gestacional (PIG) apresentam maior risco de permanecerem com baixa estatura na vida adulta. Os fatores de crescimento insulina-símile 1 e 2 (IGF-1 e IGF-2) são os principais fatores endócrinos determinantes do crescimento fetal. Na vida pós-natal o GH, principal hormônio promotor de crescimento, exerce a maior parte de seus efeitos por meio do IGF-1. A grande maioria das ações conhecidas do IGF-1 e IGF-2 são mediadas via receptor tirosina quinase conhecido como receptor tipo 1 de IGFs (IGF-1R). Os objetivos deste trabalho foram estudar os genes IGF1 e IGF1R em crianças nascidas pequenas para a idade gestacional que não recuperaram o crescimento na vida pós-natal. Foram selecionados 145 pacientes nascidos PIG, 72 sem catch up e 73 com catch up. Em 54 PIG sem catch up foi estudado toda a seqüência codificadora do gene IGF1 por meio de PCR e seqüenciamento direto, nos demais PIG sem catch up e nos 73 PIG com catch up foi estudado apenas o exon 6 do IGF-1 por PCR e seqüenciamento direto para avaliação de um polimorfismo encontrado nesta região. Nos pacientes que apresentavam concentração sérica de IGF-1 e IGFBP-3 acima da média para idade e sexo e seqüência do IGF1 normal (n=23) foi realizada coleta de sangue periférico com posterior separação de leucócitos mononucleares pelo gradiente de ficoll seguido por extração de RNA pelo método de Trizol® Posteriormente, a partir do RNA, sintetizamos o cDNA (DNA complementar) utilizando primers randômicos. Foi realizado PCR e seqüenciamento direto do cDNA, além de análise da expressão do IGF1R por PCR em tempo real. Nenhuma mutação foi encontrada no gene IGF1. Entretanto um locus altamente polimórfico foi encontrada na região 3' não traduzida do exon 6 deste gene, região esta envolvida no processo de poliadenilação. A freqüência das variantes alélicas foi semelhante em PIG com e sem catch-up e em controles nascidos AIG. Analisando o fenótipo de pacientes PIG...

Children born small for gestational age (SGA) have a higher risk of remaining short in adulthood. The insulin-like growth factors 1 and 2 (IGF-1 and IGF-2) are the main factors determining endocrine fetal growth. GH is the main promoter of linear growth in the postnatal life, exerting its effects mostly through the IGF-1. The vast majority of known actions of IGF-1 and IGF-2 are mediated by the insulin-like growth factor type 1 receptor (IGF-1R), a member of the tyrosine kinase receptors family. The aim of this study was to investigate IGF1 and IGF1R genes mutations in children born small for gestational age without catch up growth in postnatal life. We selected 145 patients born SGA, 72 without catch-up and 73 with catch up. The whole coding region of the IGF1 gene was sequenced in 54 patients without catchup. In the other SGA children without catch-up and in 73 SGA with catch-up, only the exon 6 of IGF1 was sequenced to assess the influence of allelic variants present in this region. In patients with normal IGF1 sequence and IGF-1 and IGFBP-3 serum levels above the mean for age and sex (n = 23) total RNA was extracted from peripheral blood lymphocytes followed by cDNA synthesis with random primers. The IGF1R cDNA was amplified using specific primers followed by direct sequencing. IGF1R expression was analyzed by real-time PCR. No mutations were found in the IGF1 gene. However a highly polymorphic sequence was identified in the upstream core polyadenylation signal (UCPAS) located in IGF1 3' UTR at exon 6. The frequency of the identified allelic variants was similar in SGA children with and without catch-up and in controls. Furthermore, children homozygous for the wild-type allele and those carrying the allelic variants in homozygous or heterozygous state presented similar weight and length at birth, as well as serum IGF-1 levels and postnatal growth features. Two novel nonconservative allelic variants were identified in IGF1R in 23 SGA children...

Conseqüências em longo prazo da deficiência do hormônio de crescimento / Long time consequences of the growth hormone deficiency

Este artigo descreve as conseqüências puras, em longo prazo, da deficiência isolada e vitalícia do hormônio de crescimento (GH) porque usa um modelo único de resistência ao hormônio liberador do GH (GHRH), em virtude da mutação homozigótica no gene do receptor do GHRH, em uma centena de indivíduos acometidos. Elas incluem baixa estatura grave com estatura final entre -9,6 a -5,2 desvios-padrão abaixo da média, com redução proporcional das dimensões ósseas, redução do volume da adenohipófise corrigido para o volume craniano e da tireóide, do útero, do baço e da massa ventricular esquerda, todos corrigidos para a superfície corporal, em contraste com o tamanho de pâncreas e fígado, maior que o de controles, quando igualmente corrigidos. As alterações características da composição corporal incluem redução acentuada da quantidade de massa magra (kg) e aumento do percentual de gordura com depósito predominante no abdome. Nos aspectos metabólicos são encontrados aumento de colesterol total e LDL, redução de insulina e do índice de resistência à insulina homeostasis model assessment, acompanhados de aumento da proteína C reativa de alta sensibilidade e da elevação da pressão arterial sistólica nos adultos, embora sem evidências de aterosclerose precoce. Outros achados incluem resistência óssea menor, embora acima do limiar de fraturas, puberdade atrasada, fertilidade normal, paridade diminuída, climatério antecipado e qualidade de vida normal.

This article describes the long time consequences of the isolated and lifetime growth hormone (GH) deficiency using a single model of GH releasing hormone resistance (GHRH) due to a homozygous mutation in the GHRH receptor gene, in a hundred of subjects. These consequences include severe short stature with final height between -9.6 and -5.2 standard deviations below of the mean, with proportional reductions of the bone dimensions; reduction of the anterior pituitary corrected to cranial volume and the thyroid, the uterus, the spleen and left ventricular mass volume, all corrected to body surface, in contrast of pancreas and liver size, bigger than in controls, when equally corrected. Body composition features included marked reduction in the amount of fat free mass (kg) and increase of fat mass percentage, with predominant abdominal deposit. In the metabolic aspects, we find increase in the total cholesterol and LDL cholesterol; reduction of the insulin and the insulin resistance assessed by Homeostasis model assessment; increase of ultra sensitive C reactive protein and systolic body pressure in adults, although without evidences of premature atherosclerosis. Other findings include smaller bone resistance, although above of the threshold of fractures, delayed puberty, normal fertility, small parity, anticipated climacteric and normal quality of life.

Deficiencia somatotrófica en niños: características clínicas y bioquímicas según la etiología en 75 casos / Somatotrophic deficiency in children: report of 75 cases

Somatotrophic deficiency (SDMT) can be due to a deficiency of growth hormone releasing hormone(GHRH), growth hormone (GH) or insulin like growth factor I (IGF-I). Although its clinical features have been thoroughly described, the diagnosis is still controversial. Now there is an effective treatment with GH or IGF-I for these patients. AIM: To analyze the main clinical, etiological and laboratory characteristics of 75 SD patients (44 males), aged 9.4 + 4.5 years, with severe growth retardation. The diagnosis was confirmed by the lack of response to two GH stimulation tests (Clonidine, Glugagon or Insulin) and low levels of IGF-I or insulin-like growth factor binding protein- 3 (IGFBP-3). RESULTS: In 34 patients (46 percent), the cause of DSMT was considered idiopathic (DSMT-I), in 31 (41 percent) there was an organic cause (DSMT-O), most commonly caused by malformations or pituitary tumors and in 10 (13 percent), it was genetic (DSMT-G) (three patients with Laron's Syndrome, five with mutations of GH gene and 2 with probable mutations of Prop-1 and Pit-1 genes). IGF-1 levels, were significantly lower in DSMT-O and DSMT-G thanin DSMT-I (21.2 +/- 46.1, 23.4 +/-30.3 ng/mL and 50.2 +/- 48.3 ng/mL, respectively). The lowest height score corresponded to DSMT-G, compared to DSMT-O and DSMT (­5.7 +/- 0.9, -4.0 +/- 1.6 and ­4.3 +/- 1.2 DS, respectively) CONCLUSIONS: The high percentage of organic and genetic etiologies in our patients can be due to the systematic search of these diseases. DSMT-G (Laron, mutations in GH and Pit-1 genes) had the most severe growth retardation.