RESUMO
Mosaic variegated aneuploidy syndrome (MVA) is a rare autosomal recessive disorder characterized by random chromosome gains and losses. Mutations in BUB1B and CEP57 genes have been involved in MVA. Here we report on a male child with MVA due to c.915_925dupCAATGTTCAGC mutation in the CEP57 gene. Our patient was homozygous for this mutation and he is the first case with rhizomelic shortening of both the upper and lower limbs and mild respiratory insufficiency due to a narrow thorax. It is also the second MVA Mexican family reported with this mutation that lives in the northwestern region of Mexico, suggesting a "local founding effect". Additional cases are needed to better understand the MVA genotype-phenotype relationship.
Assuntos
Transtornos Cromossômicos/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas Nucleares/genética , Transtornos Cromossômicos/patologia , Duplicação Gênica , Homozigoto , Humanos , Lactente , Masculino , MosaicismoRESUMO
Rearrangements of the distal region of 9p are important chromosome imbalances in human beings. Trisomy 9p is the fourth most frequent chromosome anomaly and is a clinically recognizable syndrome. Kleefstra syndrome, previously named 9q subtelomeric deletion syndrome, is either caused by a submicroscopic deletion in 9q34.3 or an intragenic mutation of EHMT1. We report a Mexican male patient with abnormal development, dysmorphism, systemic anomalies and a complex chromosomal rearrangement (CCR). GTG-banding revealed a 46,XY,add(9)(q34.3) karyotype, whereas array analysis resulted in arr[hg19] 9p24.3p23(203,861-11,842,172)×3, 9q34.3(138,959,881-139,753,294)×3, 9q34.3(139,784,913-141,020,389)×1. Array and karyotype analyses were normal in both parents. Partial duplication of 9p is one of the most commonly detected autosomal structural abnormalities in liveborn infants. A microdeletion in 9q34.3 corresponds to Kleefstra syndrome, whereas a microduplication in 9q34.3 shows a great clinical variability. Here, we present a CCR in a patient with multiple congenital anomalies who represents the first case with partial 9p trisomy, partial 9q trisomy and partial 9q monosomy.
Assuntos
Anormalidades Múltiplas/genética , Deleção Cromossômica , Cromossomos Humanos Par 9/genética , Translocação Genética , Trissomia , Pré-Escolar , Bandeamento Cromossômico , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , MasculinoRESUMO
Distal 15q trisomy or tetrasomy is associated with a characteristic phenotype that includes mild to moderate intellectual disability, abnormal behavior, speech impairment, overgrowth, hyperlaxity, long face, prominent nose, puffy cheeks, pointed chin, small ears, and hand anomalies (mainly arachno- and camptodactyly). We present the case of a 13-yr-old girl with the main clinical features of 15q overgrowth syndrome and a 46,XX,dup(15)(q24q26.3)[117]/46,XX[3].ish dup(15)(q24q26.3) (SNPRN+,PML+,subtel++,tel++) de novo karyotype. The findings in this case are consistent with those in the previous distal 15q trisomy cases that presented with overgrowth and mental retardation. Further, the rearranged chromosome had a double set of directly oriented telomeric and subtelomeric sequences.
Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 15 , Transtornos do Crescimento/genética , Deficiência Intelectual/genética , Telômero/química , Adolescente , Feminino , Transtornos do Crescimento/diagnóstico , Humanos , Hibridização in Situ Fluorescente , Deficiência Intelectual/diagnóstico , SíndromeRESUMO
The frequency of chromosomal alterations was compared among four children groups: those with Down syndrome and acute leukemia (DS/AL), those with acute leukemia (AL), those with only Down syndrome (DS) and healthy children (NC). The frequency of acquired chromosome abnormalities was larger in the AL group, followed by the DS/AL. The gaps and isogaps were more frequent in children with only DS. The polymorphisms of the constitutive heterochromatin were larger in the DS/AL group. These findings appear to imply that more genetic changes are necessary to develop AL in the case of healthy children compared to children with DS.
Assuntos
Análise Citogenética/métodos , Síndrome de Down/complicações , Síndrome de Down/genética , Leucemia/complicações , Leucemia/genética , Doença Aguda , Criança , Pré-Escolar , Aberrações Cromossômicas , Síndrome de Down/diagnóstico , Feminino , Humanos , Cariotipagem , Leucemia/diagnóstico , MasculinoRESUMO
El síndrome de Prader-Willi se caracteriza por hipotonía muscular, talla baja, obesidad, infantilismo sexual y retardo mental; se ha reconocido heterogeneidad genética. Se presenta un paciente de seis años de edad con estas características clínicas y con deleción 15q13--pter por translocación 5/15 familiar. Se discuten aspectos clínicos, cromosómicos y de asesoramiento genético.
Assuntos
Humanos , Masculino , Criança , Cromossomos Humanos Par 15/ultraestrutura , Aberrações Cromossômicas/genética , Síndrome de Prader-Willi/genética , Hipogonadismo/genética , Obesidade/genéticaRESUMO
La anemia de Fanconi, entidad autosómica recesiva se caracteriza por pancitopenia, malformaciones congénitas e inestabilidad cromosómica; las manifestaciones clínicas suelen iniciarse a los seis años de edad. Se presenta un paciente de 19 meses de edad cuyo diagnóstico se estableció en fase preanémica. Se discuten aspectos génicos y cromosómicos de la entidad y la importancia de establecer el diagnóstico en etapa temprana.