Electronic Resource
A complete duplication of X chromosome resulting in a tricentric isochromosome originated by centromere repositioning
| العنوان: | A complete duplication of X chromosome resulting in a tricentric isochromosome originated by centromere repositioning |
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| المؤلفون: | Villa, N, Conconi, D, Gambel Benussi, D, Tornese, G, Crosti, F, Sala, E, Dalpra', L, Pecile, V, VILLA, NICOLETTA, CONCONI, DONATELLA, CROSTI, FRANCESCA, SALA, ELENA MARIA, DALPRA', LEDA, Pecile, V. |
| بيانات النشر: | BioMed Central Ltd. 2017 |
| نوع الوثيقة: | Electronic Resource |
| مستخلص: | Background: Neocentromeres are rare and considered chromosomal aberrations, because a non-centromeric region evolves in an active centromere by mutation. The literature reported several structural anomalies of X chromosome and they influence the female reproductive capacity or are associated to Turner syndrome in the presence of monosomy X cell line. Case presentation: We report a case of chromosome X complex rearrangement found in a prenatal diagnosis. The fetal karyotype showed a mosaicism with a 45,X cell line and a 46 chromosomes second line with a big marker, instead of a sex chromosome. The marker morphology and fluorescence in situ hybridization (FISH) characterization allowed us to identify a tricentric X chromosome constituted by two complete X chromosome fused at the p arms telomere and an active neocentromere in the middle, at the union of the two Xp arms, where usually are the telomeric regions. FISH also showed the presence of a paracentric inversion of both Xp arms. Furthermore, fragility figures were found in 56% of metaphases from peripheral blood lymphocytes culture at birth: a shorter marker chromosome and an apparently acentric fragment frequently lost. Conclusions: At our knowledge, this is the first isochromosome of an entire non-acrocentric chromosome. The neocentromere is constituted by canonical sequences but localized in an unusual position and the original centromeres are inactivated. We speculated that marker chromosome was the result of a double rearrangement: firstly, a paracentric inversion which involved the Xp arm, shifting a part of the centromere at the p end and subsequently a duplication of the entire X chromosome, which gave rise to an isochromosome. It is possible to suppose that the first event could be a result of a non-allelic homologous recombination mediated by inverted low-copy repeats. As expected, our case shows a Turner phenotype with mild facial features and no major skeletal deformity, normal psychomotor development a |
| مصطلحات الفهرس: | Chromosome complex rearrangement, Telomeric-centromeric X rearrangement, Genetics (clinical), info:eu-repo/semantics/article |
| URL: | info:eu-repo/semantics/altIdentifier/pmid/28630649 info:eu-repo/semantics/altIdentifier/wos/WOS:000403290600001 volume:10 issue:1 journal:MOLECULAR CYTOGENETICS |
| الاتاحة: | Open access content. Open access content |
| ملاحظة: | English |
| Other Numbers: | ITBAO oai:boa.unimib.it:10281/161028 10.1186/s13039-017-0323-7 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85020705645 1308921536 |
| المصدر المساهم: | BICOCCA OPEN ARCH From OAIster®, provided by the OCLC Cooperative. |
| رقم الانضمام: | edsoai.on1308921536 |
| قاعدة البيانات: | OAIster |
| الوصف غير متاح. |