RESUMO
Two unrelated children were found to have de novo opposite imbalances for distal 14q. One had a 46,XY, del(14)(q24q32) karyotype and exhibited, like three other patients with similar deletions, a distinctive facial appearance including round face, frontal hypertrichosis, thick eyebrows, horizontal narrow palpebral fissures, a short bulbous nose with a flat root, and mild micrognathia. The other had a 46,XX, dir dup(14)(q22----q32) karyotype and stigmata common to patients with comparable duplications, namely high forehead, sparse eyebrows, prominent overlip, gingival hypertrophy, and overriding fingers. Therefore, it is concluded that each of these imbalances originates a distinct syndrome.
Assuntos
Aberrações Cromossômicas/genética , Deleção Cromossômica , Cromossomos Humanos Par 14 , Família Multigênica/genética , Transtornos Cromossômicos , Face/patologia , Feminino , Humanos , Lactente , Recém-Nascido , Cariotipagem , Masculino , Fenótipo , SíndromeRESUMO
An azoospermic male with a 46,X,t(Y;19)(q12;q13) karyotype is described. The comparison with 12 similar cases reveals that the Y breakpoints are usually on the long arm whereas the autosomal ones seem to be at random. Since a premeiotic origin is inconsistent with the arrest at diakinesis seen in those cases with meiotic studies, we postulate that a balanced t(Y;A) arises either via a chromatid exchange in the meiotic interphase or through a chromosome exchange in spermiogenesis or at the one cell stage of the zygote.
