Embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development.

Balanced chromosomal rearrangements represent one of the most common forms of genetic abnormality affecting approximately 1 in every 500 (0.2%) individuals. Difficulties processing the abnormal chromosomes during meiosis lead to an elevated risk of chromosomally abnormal gametes, resulting in high r...

Full description

Saved in:
Bibliographic Details
Main Authors: Samer Alfarawati, Elpida Fragouli, Pere Colls, Dagan Wells
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2012-01-01
Series:PLoS Genetics
Online Access:https://journals.plos.org/plosgenetics/article/file?id=10.1371/journal.pgen.1003025&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849720247656906752
author Samer Alfarawati
Elpida Fragouli
Pere Colls
Dagan Wells
author_facet Samer Alfarawati
Elpida Fragouli
Pere Colls
Dagan Wells
author_sort Samer Alfarawati
collection DOAJ
description Balanced chromosomal rearrangements represent one of the most common forms of genetic abnormality affecting approximately 1 in every 500 (0.2%) individuals. Difficulties processing the abnormal chromosomes during meiosis lead to an elevated risk of chromosomally abnormal gametes, resulting in high rates of miscarriage and/or children with congenital abnormalities. It has also been suggested that the presence of chromosome rearrangements may also cause an increase in aneuploidy affecting structurally normal chromosomes, due to disruption of chromosome alignment on the spindle or disturbance of other factors related to meiotic chromosome segregation. The existence of such a phenomenon (an inter-chromosomal effect--ICE) remains controversial, with different studies presenting contradictory data. The current investigation aimed to demonstrate conclusively whether an ICE truly exists. For this purpose a comprehensive chromosome screening technique, optimized for analysis of minute amounts of tissue, was applied to a unique collection of samples consisting of 283 oocytes and early embryos derived from 44 patients carrying chromosome rearrangements. A further 5,078 oocytes and embryos, derived from chromosomally normal individuals of identical age, provided a robust control group for comparative analysis. A highly significant (P = 0.0002) increase in the rate of malsegregation affecting structurally normal chromosomes was observed in association with Robertsonian translocations. Surprisingly, the ICE was clearly detected in early embryos from female carriers, but not in oocytes, indicating the possibility of mitotic rather than the previously suggested meiotic origin. These findings have implications for our understanding of genetic stability during preimplantation development and are of clinical relevance for patients carrying a Robertsonian translocation. The results are also pertinent to other situations when cellular mechanisms for maintaining genetic fidelity are relaxed and chromosome rearrangements are present (e.g. in tumors displaying chromosomal instability).
format Article
id doaj-art-3964a4bbbe004e7195b46c1a2b71508d
institution DOAJ
issn 1553-7390
1553-7404
language English
publishDate 2012-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Genetics
spelling doaj-art-3964a4bbbe004e7195b46c1a2b71508d2025-08-20T03:11:58ZengPublic Library of Science (PLoS)PLoS Genetics1553-73901553-74042012-01-01810e100302510.1371/journal.pgen.1003025Embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development.Samer AlfarawatiElpida FragouliPere CollsDagan WellsBalanced chromosomal rearrangements represent one of the most common forms of genetic abnormality affecting approximately 1 in every 500 (0.2%) individuals. Difficulties processing the abnormal chromosomes during meiosis lead to an elevated risk of chromosomally abnormal gametes, resulting in high rates of miscarriage and/or children with congenital abnormalities. It has also been suggested that the presence of chromosome rearrangements may also cause an increase in aneuploidy affecting structurally normal chromosomes, due to disruption of chromosome alignment on the spindle or disturbance of other factors related to meiotic chromosome segregation. The existence of such a phenomenon (an inter-chromosomal effect--ICE) remains controversial, with different studies presenting contradictory data. The current investigation aimed to demonstrate conclusively whether an ICE truly exists. For this purpose a comprehensive chromosome screening technique, optimized for analysis of minute amounts of tissue, was applied to a unique collection of samples consisting of 283 oocytes and early embryos derived from 44 patients carrying chromosome rearrangements. A further 5,078 oocytes and embryos, derived from chromosomally normal individuals of identical age, provided a robust control group for comparative analysis. A highly significant (P = 0.0002) increase in the rate of malsegregation affecting structurally normal chromosomes was observed in association with Robertsonian translocations. Surprisingly, the ICE was clearly detected in early embryos from female carriers, but not in oocytes, indicating the possibility of mitotic rather than the previously suggested meiotic origin. These findings have implications for our understanding of genetic stability during preimplantation development and are of clinical relevance for patients carrying a Robertsonian translocation. The results are also pertinent to other situations when cellular mechanisms for maintaining genetic fidelity are relaxed and chromosome rearrangements are present (e.g. in tumors displaying chromosomal instability).https://journals.plos.org/plosgenetics/article/file?id=10.1371/journal.pgen.1003025&type=printable
spellingShingle Samer Alfarawati
Elpida Fragouli
Pere Colls
Dagan Wells
Embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development.
PLoS Genetics
title Embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development.
title_full Embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development.
title_fullStr Embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development.
title_full_unstemmed Embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development.
title_short Embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development.
title_sort embryos of robertsonian translocation carriers exhibit a mitotic interchromosomal effect that enhances genetic instability during early development
url https://journals.plos.org/plosgenetics/article/file?id=10.1371/journal.pgen.1003025&type=printable
work_keys_str_mv AT sameralfarawati embryosofrobertsoniantranslocationcarriersexhibitamitoticinterchromosomaleffectthatenhancesgeneticinstabilityduringearlydevelopment
AT elpidafragouli embryosofrobertsoniantranslocationcarriersexhibitamitoticinterchromosomaleffectthatenhancesgeneticinstabilityduringearlydevelopment
AT perecolls embryosofrobertsoniantranslocationcarriersexhibitamitoticinterchromosomaleffectthatenhancesgeneticinstabilityduringearlydevelopment
AT daganwells embryosofrobertsoniantranslocationcarriersexhibitamitoticinterchromosomaleffectthatenhancesgeneticinstabilityduringearlydevelopment