RESUMO
4p Monosomy and 12p trisomy have been discussed and redefined along with recently reviewed chromosomal syndromes. 12p Trisomy syndrome is characterized by normal or increased birth weight, developmental delay with early hypotonia, psychomotor delay, and typical facial appearance. Most likely, the observed phenotypic variability depends on the type and extent of the associated partial monosomy. Partial deletions of the short arm of one chromosome 4 cause the Wolf-Hirschhorn syndrome (WHS). Affected patients present Greek helmet face, growth and mental retardation, hypotonia, and seizures. The combination of these characteristics constitutes the phenotypic core of WHS. We present a clinical and molecular cytogenetic characterization of a 4-year old mentally retarded girl with macrosomy, facial dysmorphisms, and epilepsy, in whom an unbalanced t(4;12)(p16.3;p13.3) translocation was detected, giving rise to partial 4p monosomy and partial 12p trisomy. Because the patient shows most of the phenotypic characteristics of 12p trisomy, this case could contribute to a better definition of the duplicate critical region that determines the phenotype of the 12p trisomy syndrome.
Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 4/genética , Trissomia/genética , Síndrome de Wolf-Hirschhorn/genética , Pré-Escolar , Bandeamento Cromossômico , Deleção Cromossômica , Cromossomos Artificiais Bacterianos , Epilepsia/genética , Fácies , Feminino , Genótipo , Humanos , Hibridização in Situ Fluorescente , Deficiência Intelectual/genética , Cariotipagem , Sondas Moleculares , Hipotonia Muscular/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Translocação Genética/genéticaRESUMO
The 4q deletion syndrome shows varying phenotype, ranging from severe and complex malformations, unconformable with life, to more specific findings, as genitourinary, gastrointestinal and cardiac malformations, cleft palate,microcephaly, hypertelorism and abnormal ears and limbs. Strabismus, nystagmus, ophthalmoplegia, and optic nerve anomalies have been rarely described in literature. We report an original case of simultaneous deletion and duplication of chromosome 4q, confirmed by SNPs-array analysis of DNA, and characterized by a previously unreported association between optic nerve hypoplasia and progressive external ophthalmoplegia.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 4/genética , Anormalidades Craniofaciais/genética , Duplicação Gênica , Oftalmoplegia Externa Progressiva Crônica/genética , Nervo Óptico/anormalidades , Criança , Anormalidades Craniofaciais/diagnóstico , Humanos , Masculino , Oftalmoplegia Externa Progressiva Crônica/diagnóstico , Polimorfismo de Nucleotídeo ÚnicoAssuntos
Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/diagnóstico por imagem , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/genética , Análise Citogenética , Diagnóstico Pré-Natal/métodos , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Hibridização in Situ Fluorescente , Gravidez , Complicações na Gravidez/diagnósticoRESUMO
We report on a 3-year-old male with developmental delay, autistic behavior, and minor abnormalities consistent with trisomy 8 syndrome whose cytogenetic analysis revealed mosaicism for a supernumerary ring chromosome (SRC). Fluorescence in situ hybridization (FISH) studies, using centromeric and yeast artificial chromosome (YAC) probes, were performed to characterize further the supernumerary chromosome. The ring origin has been detected from the short arm of chromosome 8, resulting in r(8)(p10p23.1). Moreover, uniparental disomy (UPD) using microsatellite analysis was excluded. To our knowledge a total of 25 cases, confirmed by FISH, have been reported with either supernumerary marker or ring chromosome 8. We present a detailed clinical and molecular cytogenetic characterization of this additional case in order to better define the genotype-phenotype correlation.
