RESUMO
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.
Assuntos
Humanos , Hibridização in Situ Fluorescente , Síndrome de DiGeorge , Síndrome da Deleção 22q11 , Endocrinologia , GenéticaRESUMO
El síndrome 47, XXX se debe a un cromosoma extra del par sexual; su incidencia es de 1 en 1000 recién nacidas vivas. Sin embargo, este síndrome no suele sospecharse al nacimiento ni en la infancia. Muchas de estas pacientes son diagnosticadas durante la edad adulta por falla ovárica precoz o esterilidad, debido a la falta de características clínicas específicas .Este trabajo describe cuatro casos de pacientes 47, XXX y su variabilidad fenotípica.
The 47, XXX karyotype has a frequency of 1 in 1000 female newborns. However, this karyotype is not usually suspected at birth or childhood. These patients are usually diagnosed duringadulthood when they develop premature ovarian failure or infertility, because the early phenotype doesn't have anyspecific features. The study describes four cases and the clinical variability of the 47, XXX karyotype.
Assuntos
Humanos , Feminino , Aneuploidia , Doenças Genéticas Ligadas ao Cromossomo X , Fenótipo , Transtornos dos Cromossomos SexuaisRESUMO
The location of 18S and 5S rDNA sites was determined in eight species and populations of the fish genus Triportheus by using fluorescent in situ hybridization (FISH). The males and females of all species had 2n = 52 chromosomes and a ZZ/ZW sex chromosome system. A single 18S rDNA site that was roughly equivalent to an Ag-NOR was detected on the short arms of a submetacentric pair in nearly all species, and up to two additional sites were also observed in some species. In addition, another 18S rDNA cluster was identified in a distal region on the long arms of the W chromosome; this finding corroborated previous evidence that this cluster would be a shared feature amongst Triportheus species. In T. angulatus, a heterozygotic paracentric inversion involving the short arms of one homolog of a metacentric pair was associated with NORs. The 5S rDNA sites were located on the short arms of a single submetacentric chromosomal pair, close to the centromeres, except in T. auritus, which had up to ten 5S rDNA sites. The 18S and 5S rDNA sites were co-localized and adjacent on the short arms of a chromosomal pair in two populations of T. nematurus. Although all Triportheus species have a similar karyotypic macrostructure, the results of this work show that in some species ribosomal genes may serve as species-specific markers when used in conjunction with other putatively synapomorphic features.