A homozygous mutation in the highly conserved Tyr60 of the mature IGF1 peptide broadens the spectrum of IGF1 deficiency.

BACKGROUND: IGF1 is a key factor in fetal and postnatal growth. To date, only three homozygous IGF1 gene defects leading to complete or partial loss of IGF1 activity have been reported in three short patients born small for gestational age. We describe the fourth patient with severe short stature presenting a novel homozygous IGF1 gene mutation. RESULTS: We report a boy born from consanguineous parents at 40 weeks of gestational age with intrauterine growth restriction and severe postnatal growth failure. Physical examination revealed proportionate short stature, microcephaly, facial dysmorphism, bilateral sensorineural deafness and mild global developmental delay. Basal growth hormone (GH) fluctuated from 0.2 to 29 ng/mL, while IGF1 levels ranged from -1.15 to 2.95 SDS. IGFBP3 was normal-high. SNP array delimited chromosomal regions of homozygosity, including 12q23.2 where IGF1 is located. IGF1 screening by HRM revealed a homozygous missense variant NM_000618.4(IGF1):c.322T>C, p.(Tyr108His). The change of the highly conserved Tyr60 in the mature IGF1 peptide was consistently predicted as pathogenic by multiple bioinformatic tools. Tyr60 has been described to be critical for IGF1 interaction with type 1 IGF receptor (IGF1R). In vitro, HEK293T cells showed a marked reduction of IGF1R phosphorylation after stimulation with serum from the patient as compared to sera from age-matched controls. Mutant IGF1 was also less efficient in inducing cell growth. CONCLUSION: The present report broadens the spectrum of clinical and biochemical presentation of homozygous IGF1 defects and underscores the variability these patients may present depending on the IGF/IGF1R pathway activity.

Establishment of testicular endocrine function impairment during childhood and puberty in boys with Klinefelter syndrome.

OBJECTIVE: To precisely characterize the chronology of testicular endocrine function impairment during childhood and adolescence in patients with Klinefelter syndrome. Design Retrospective chart review. Patients A total of 29 boys with Klinefelter syndrome with up to 12.3 years follow-up. MEASUREMENTS: Clinical features and serum hormone levels were analysed during follow-up. RESULTS: Of the 29 patients, 16 were prepubertal and 13 had already entered puberty at their first visit. Fifteen patients were followed up through late puberty. Before puberty, LH, FSH, testosterone, anti-Müllerian hormone (AMH) and inhibin B were within the expected range in almost all cases. However, levels of the inhibin alpha-subunit precursor Pro-alphaC were in the lowest levels of the normal range in most cases. During puberty, FSH levels increased earlier and more markedly than LH. Inhibin B and AMH declined to abnormally low or undetectable levels in advanced pubertal stages. Although testosterone and Pro-alphaC levels were within the reference ranges in most cases, they were abnormally low for the observed LH values. CONCLUSIONS: In Klinefelter syndrome, a mild Leydig cell dysfunction is present from early childhood in most cases and persists throughout puberty. Sertoli cell function is normal until mid puberty, when a dramatic impairment is observed.

Familial occurrence of the IMAGe association: additional clinical variants and a proposed mode of inheritance.

The IMAGe (intrauterine growth retardation, metaphyseal dysplasia, adrenal hypoplasia congenita, genital anomalies) association (online inheritance in man 300290) is a recently reported disorder comprising intrauterine growth retardation (IUGR), metaphyseal dysplasia, adrenal hypoplasia, and genital anomalies. Four children (three males, one female) from a large pedigree (five generations) were studied. Additional members (n = 10), who died during the neonatal period, were born with IUGR and/or hyperpigmentation and are presumed to have been affected, too. All patients in this series were diagnosed during the newborn period. Minimal clinical features and laboratory findings differ with previously reported patients, suggesting variants in their clinical expression. Adrenal insufficiency was variable within patients. All had severe IUGR and marked postnatal growth failure. Sequence analysis of DNA using an automated cycle from two patients revealed no mutation in the dosage-sensitive sex reversal-adrenal hypoplasia congenita critical region on the X chromosome, gene 1. Analysis of the pedigree showed that the disease is inherited via the maternal line, even in the dead children with suspicion of the disease. Hence, the pattern of inheritance in this family of this unusual disorder might be explained in terms of the genomic imprinting hypothesis with expression through maternal transmission involving an autosomal gene. This transmission may have considerable implications for genetic counseling. Furthermore, pediatric endocrinologists must be aware of the possible occurrence of this life-threatening condition in the offspring of nonaffected women when related to a family member with the association of IUGR, metaphyseal dysplasia, adrenal hypoplasia congenita, genital anomalies.

Aplicación de Hibridación In Situ Fluorescente (FISH) en pacientes con sospecha clínica de Síndrome de Deleción 22q11. 2 (SD22q11. 2) / Applying Fluorescent in situ hy-bridiza on (FISH) in patients with suspected clinical signs of 22q11. 2 dele on syndrome (DS22q11. 2)

El SD22q11.2 está asociado a síndromes de DiGeorge, velocardiofacial, facioconotruncal y Cayler, reconocidos con la misma etiología: microdeleción 22q11.2. El fenotipo es variable y presenta cardiopatía conotruncal (CC), dismorfias faciales, anomalías palatinas, inmunodeficiencias y trastornos del neurodesarrollo. Las manifestaciones endocrinológicas que predominan son talla baja, hipocalcemia neonatal asociada a hipoparatiroidismo y disfunción tiroidea. El 90% de los afectados presenta una deleción típica de 3-Mb, mientras que el resto tiene deleciones de menor tamaño o deleción localizada más distal a la región crítica . El objetivo del trabajo es identificar en una cohorte de 63 pacientes con sospecha clínica de SD22q11.2, la presencia de la microdeleción 22q11.2 empleando como método diagnóstico la técnica de FISH y describir brevemente las características clínicas más prevalentes que presentan los pacientes con resultado de FISH positivo y negativo. La microdeleción 22q11.2 se identificó en el 38% (24/63) de los pacientes estudiados. Las características clínicas más prevalentes en este grupo fueron las cardiopatías congénitas conotruncales (95,6%), microcefalia (50%), inmunodeficiencias (50%), hipocalcemia (48,8%), anomalías del paladar (45,8%), retraso del desarrollo y déficit cognitivo (41,5%). En nuestro hospital, el algoritmo diagnóstico para la detección de la microdeleción 22q11.2 es el cariotipo de alta resolución y el estudio por la técnica de FISH.

DS22q11.2 is associated with a wide spectrum of clinical disorders (DiGeorge, velocardiofacial, facioconotrunal and Cayler syndromes) known to arise from the same etiology 22q11.2 microdeletion The phenotype is variable and includes conotruncal cardiac defect (CCD), facial phenotype, palate anomalies, inmunodeficiency and developmental disorders. The endocrine manifestations are short stature (ST), neonatal hypocalcemia due to hypoparathyroidism, and thyroid dysfunction. In 90% of patients with 22q11.1 deletion a common 3-Mb deletion has been found, whereas the rest of cases share a smaller deletion or more distal atypical deletions. The aim of the present study was to identify the 22q11.2 microdeletion by FISH in 63 patients from the Genetic and Endocrinology Division between 2002 and 2017 who had more than one clinical feature of DS22q11. 2. High resolution karyotype and fluorescent in situ hybridization (FISH) were performed with different commercial probes. The 22q11.2 microdeletion was demonstrated in 24/63 patients (38%). The more relevant clinical features in this group were: conotruncal cardiac defect (95.6%), microcephaly (50%), immunodeficiency (50%), hypocalcaemia (48.8%) palate anomalies (45.8%), development delay and cognitive deficit (41.5%). In our hospital, the diagnostic algorithm for the detection of the 22q11.2 microdeletion is the high resolution karyotype and the study by the FISH technique.

Síndrome de Turner: variaciones en la constitución cromosómica y sus efectos en la expresión fenotípica / Turner Syndrome: variations in the chromosomal constitution and its effects on the phenotypic expression

El Síndrome de Turner es un desorden cromosómico causado por haploinsuficiencia completa o parcial de uno de los cromosomas sexuales. Incidencia 1: 2500 recién nacidas vivas. Clínicamente las pacientes presentan talla baja, un espectro amplio de anomalías somáticas y disgenesia gonadal. Desde el año 1968 hasta el presente se estudiaron clínica y citogenéticamente 630 niñas con fenotipo de Turner, sin ambigüedad genital y con cariotipos anormales, quienes consultaron en la División de Endocrinología del Hospital de Niños "Ricardo Gutiérrez". Se realizó cariotipo en sangre, al inicio con metodología estándar, luego con diferentes bandeos convencionales y de alta resolución. En casos especiales se aplicó la técnica FISH y el análisis molecular de los cromosomas X e Y. El número de metafases analizadas también varió con el tiempo, permitiendo evidenciar más de una línea celular. En casos de alta sospecha clínica, la lectura de 100 metafases permitió poner en evidencia mosaicismos bajos conteniendo la línea 45,X. En nuestra serie la monosomía de cromosoma sexual 45, X fue la más frecuente siguiendo los mosaicos numéricos y estructurales de uno de los cromosomas sexuales. Los diferentes hallazgos cromosómicos nos han permitido establecer una correlación fenotipo-cariotipo en regiones específicas de los cromosomas sexuales

Turner Syndrome is a common chromosomal disorder caused by total or partial haploinsufficiency of one of the sex chromosomes. Incidence: 1: 2500. Clinically is characterized by short stature, several typical somatic features, and gonadal dysgenesis. This is a retrospective study involving 630 girls with Turner phenotype and abnormal karyotype, evaluated at the Endocrinology Division of Children´s Hospital "Ricardo Gutiérrez" between 1968 and 2018. The karyotype was done in leucocytes from peripheral blood and the metaphases were analyzed at the beginning with standard methodology and then with different banding techniques, standard and high resolution. In special cases, the FISH technique and the molecular analysis of the X and Y chromosomes were applied. The number of metaphases analyzed also changed with time, allowing the finding of more than one cellular line. In cases where the clinical suspicion was strong, the analysis of 100 metaphases allowed us to put in evidence low mosaicisms containing the 45,X line. In our study the monosomy of sexual chromosome 45, X was the most frequent following the numerical and structural mosaics of one of the sex chromosomes. The different chromosomal constitutions have contributed to establish in our patients phenotype-karyotype correlation with specific regions of the sex chromosomes

Trisomy of the short stature homeobox-containing gene (SHOX) due to duplication/deletion of the X chomosome: clinical implications on the stature.

BACKGROUND: The karyotypes of 2 patients with abnormal stature and different phenotypes revealed one similar structural abnormality in the X chromosome by conventional cytogenetic studies and fluorescence in situ hybridization analysis (FISH). FISH strongly suggested the presence of two copies of the SHOX gene in the der(X) chromosome. PATIENTS AND RESULTS: Patient 1 is a teenager girl with tall stature, behavioral disturbances and normal pubertal development. The abnormal X chromosome was present in all cells studied. Parent's karyotypes were normal. Patient 2 is a girl with gonadal dysgenesis, mild Turner syndrome phenotype and short stature. The karyotype was a mosaic 45,X/46,X,r(X) and der(X) chromosome presented in most metaphases of the cell lines. Parent's karyotypes were normal. Nearly all duplication of Xp and partial deletion of the long arm (Xq) from Xq27 or Xq21 to Xqter, in cases 1 and 2, respectively, were observed. In both patients, duplication of Xp translocated to deleted Xq occurred leading to a triplication of the pseudoautosomal region 1 (PAR1) where the SHOX gene is located (Xp22.3). CONCLUSIONS: We propose that in some cases of trisomy for the SHOX gene, the effect of overdosage per se may affect the stature, even in patients with preserved ovarian function (case 1), and that estrogen deprivation may not always be a contributor for tall stature (case 2).

Síndrome de Rokitansky (agenesia úterovaginal): aspectos clínicos, diagnósticos y terapéuticos / Rokitansky syndrome(uterine vaginal agenesis): clinical, diagnostic and therapeutic aspects

RESUMEN. Introducción. El síndrome de Rokitansky es unaanomalía grave del tracto reproductivo femenino,con ausencia de menarca e imposibilidad deembarazo.Objetivo. Analizar las características clínicas, diagnósticas,terapéuticas y evolutivas de un grupo deadolescentes afectadas.Material y métodos. Nueve adolescentes (15,2 ± 1,5años) que consultaron por ausencia de menarca odolor pelviano se evaluaron mediante examen físico,ecografía ginecológica, resonancia nuclear magnéticaabdominopelviana, cariotipo, dosajes hormonalesy laparoscopia. El diagnóstico final fue desíndrome de RokitanskyResultados. Todas las pacientes tuvieron caracteressexuales secundarios normales. Tres presentaronanomalías renales y tres anomalías esqueléticas.La ecografía mostró útero ausente, rudimentarioo asimétrico, este último con hematómetra evidenciadopor resonancia nuclear magnética. Lalaparoscopia detectó anomalías tubarias u ováricasen seis casos. Mediante estos estudios, cinco denuestras pacientes se clasificaron como pertenecientesa la forma B (atípica) del síndrome. Dospacientes tuvieron cariotipos anormales: 46, X, del(X) (q22q24) y 46,XX, t (3;22) (q13.3, q 12.1), ambassin insuficiencia ovárica. Seis pacientes tuvieronconcentraciones hormonales normales, una presentóhiperplasia suprarrenal congénita de formano clásica, confirmada por estudio molecular y otramostró alteraciones compatibles con síndrome depoliquistosis ovárica. En seis pacientes se efectuóplástica de vagina con resultado satisfactorio