| Author | Moraes, Lucia M. | |
| Author | Cardoso, Leila C. A. | |
| Author | Moura, Vera L. S. | |
| Author | Moreira, Miguel A. M. | |
| Author | Menezes, Albert N. | |
| Author | Llerena Junior, Juan Clinton | |
| Author | Seuánez, Héctor N. | |
| Access date | 2015-05-05T14:47:54Z | |
| Available date | 2015-05-05T14:47:54Z | |
| Document date | 2009 | |
| Citation | MORAES, Lucia M. et al. Detailed analysis of x chromosome inactivation in a 49,xxxxx pentasomy. Molecular Cytogenetics, v. 2, n. 20, p. 1-13, 2009. | pt_BR |
| ISSN | 1755-8166 | |
| URI | https://www.arca.fiocruz.br/handle/icict/10237 | |
| Language | eng | pt_BR |
| Publisher | BioMed Central | pt_BR |
| Rights | open access | pt_BR |
| Title | Detailed analysis of X chromosome inactivation in a 49,XXXXX pentasomy | pt_BR |
| Type | Article | pt_BR |
| DOI | 10.1186/1755-8166-2-20 | pt_BR |
| Abstract | Pentasomy X (49,XXXXX) has been associated with a severe clinical condition, presumably resulting from failure or disruption of X chromosome inactivation. Here we report that some human X chromosomes from a patient with 49,XXXXX pentasomy were functionally active following isolation in inter-specific (human-rodent) cell hybrids. A comparison with cytogenetic and molecular findings provided evidence that more than one active X chromosome was likely to be present in the cells of this patient, accounting for her abnormal phenotype. Results: 5-bromodeoxyuridine (BrdU)-pulsed cultures showed different patterns among late replicating X chromosomes suggesting that their replication was asynchronic and likely to result in irregular inactivation. Genotyping of the proband and her mother identified four maternal and one paternal X chromosomes in the proband. It also identified the paternal X chromosome haplotype (P), indicating that origin of this X pentasomy resulted from two maternal, meiotic nondisjunctions. Analysis of the HUMANDREC region of the androgen receptor (AR) gene in the patient's mother showed a skewed inactivation pattern, while a similar analysis in the proband showed an active paternal X chromosome and preferentially inactivated X chromosomes carrying the 173 AR allele. Analyses of 33 cell hybrid cell lines selected in medium containing hypoxanthine, aminopterin and thymidine (HAT) allowed for the identification of three maternal X haplotypes (M1, M2 and MR) and showed that X chromosomes with the M1, M2 and P haplotypes were functionally active. In 27 cell hybrids in which more than one X haplotype were detected, analysis of X inactivation patterns provided evidence of preferential inactivation. Conclusion: Our findings indicated that 12% of X chromosomes with the M1 haplotype, 43.5% of X chromosomes with the M2 haplotype, and 100% of the paternal X chromosome (with the P haplotype) were likely to be functionally active in the proband's cells, a finding indicating that disruption of X inactivation was associated to her severe phenotype. | pt_BR |
| Affilliation | Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Genética Médica. Rio de Janeiro, RJ, Brasil. | pt_BR |
| Affilliation | Instituto Nacional de Câncer. Divisão Genética. Rio de Janeiro, RJ, Brasil. / Universidade Federal do Rio de Janeiro. Departamento de Genética. Rio de Janeiro, RJ, Brasil. | pt_BR |
| Affilliation | Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Genética Médica. Rio de Janeiro, RJ, Brasil. | pt_BR |
| Affilliation | Instituto Nacional de Câncer. Divisão Genética. Rio de Janeiro, RJ, Brasil. | pt_BR |
| Affilliation | Instituto Nacional de Câncer. Divisão Genética. Rio de Janeiro, RJ, Brasil. / Universidade Federal do Rio de Janeiro. Departamento de Genética. Rio de Janeiro, RJ, Brasil. | pt_BR |
| Affilliation | Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Genética Médica. Rio de Janeiro, RJ, Brasil. | pt_BR |
| Affilliation | Instituto Nacional de Câncer. Divisão Genética. Rio de Janeiro, RJ, Brasil. / Universidade Federal do Rio de Janeiro. Departamento de Genética. Rio de Janeiro, RJ, Brasil. | pt_BR |
| Subject | X chromosome | pt_BR |
| Subject | Pentasomy X (49,XXXXX) | pt_BR |
| Subject | Cytogenetic | pt_BR |
| DeCS | Cromossomos | pt_BR |
| DeCS | Células | pt_BR |
| DeCS | Células Híbridas | pt_BR |
