Golzio C, Guirchoun J, Ozilou C, Thomas S, Goudefroye G, Morichon-Delvallez N, Vekemans M, Attié-Bitach T, Etchevers HC. Cytogenetic and histological features of a human embryo with homogeneous chromosome 8 trisomy.
Prenat Diagn 2007;
26:1201-5. [PMID:
17075794 DOI:
10.1002/pd.1588]
[Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND
Homogeneous and complete trisomy 8 is extremely rare. With one recent neonatal exception, all reported cases have been mosaic, due to mitotic non-disjunction during early zygotic development. We report a case of chromosome 8 trisomy in a human embryo examined at Carnegie stage 11 (25 days post-fertilization). It presented severe cardiovascular and central nervous system malformations.
METHODS
The unusual bifid heart in this embryo spurred a detailed histological examination, karyotyping of a chorionic villus sample and subsequent FISH on inter-phase nuclei of intra-embryonic sections.
RESULTS
Trophoblast cells had a karyotype of 47,XX, +8. Within the embryo proper, FISH demonstrated that the trisomy 8 was homogeneous in embryonic as well as extra-embryonic tissues. FQ-PCR supports a meiosis I origin of non-disjunction. In sections, the pharyngeal arches (including cardiac outflow tract), forebrain, mesonephros and liver were absent. Somites and yolk sac blood vessels were irregularly shaped.
CONCLUSION
We show that homogeneous, intra-embryonic trisomy 8 is compatible with implantation and early human development. Molecular pathways that may be compromised and their impact on organogenesis are discussed.
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