Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-10T16:32:42.196Z Has data issue: false hasContentIssue false

Absence of Genomic Imprinting at the DiGeorge Locus

Published online by Cambridge University Press:  01 August 2014

D. Theophile
Affiliation:
Laboratoire d'Histologie-Embryologie et de Cytogénétique, Hopital Necker-Enfants-Malades, Paris, France
D. Bérubé
Affiliation:
Laboratoire d'Histologie-Embryologie et de Cytogénétique, Hopital Necker-Enfants-Malades, Paris, France
J. Augé
Affiliation:
Laboratoire d'Histologie-Embryologie et de Cytogénétique, Hopital Necker-Enfants-Malades, Paris, France
M. Vekemans*
Affiliation:
Laboratoire d'Histologie-Embryologie et de Cytogénétique, Hopital Necker-Enfants-Malades, Paris, France
*
Laboratoire Histologie-Embryologie Cytogenetique, Hopital Necker, 149, rue de Sevres F-75015 Paris, France

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Fluorescence in situ hybridization (FISH) has been used to visualize specific genomic DNA sequences in interphase nuclei. Timing of replication can be measured by FISH to interphase nuclei: nuclei with a sequence that has not replicated reveal two single signals (G1), whereas those in which the sequence has replicated show two signal doublets (G2). Asynchronous nuclei show a single signal on one allele and a double hybridization dot on the other homologue. In general, most sequences replicate synchronously on the two homologues, with only 10% of nuclei showing an asynchronous hybridization pattern. However, for the sequences known about to be imprinted, approximately 30% of nuclei reveal asynchronous replication. Little is known whether or not the proximal region of chromosome 22, involved in the DiGeorge syndrome [1], is imprinted. We have, therefore, examined the replication timing pattern of the DiGeorge critical region (DGCR).

Type
Research Article
Copyright
Copyright © The International Society for Twin Studies 1996

References

REFERENCES

1. Halford, S, Wilson, D, Daw, S, Roberts, C, Wadey, R, Kamath, S, Wickremasinghe, A, Burn, J, Goodship, J, Mattei, M, Moormon, A, Scambler, P: Isolation of a gene expressed during early embryogenesis from the region of 22q11 commonly deleted in DiGeorge syndrome. Hum Mol Genet 1993; 2: 15771582.Google Scholar
2. Kitsberg, D, Seilig, S, Brandeis, M, Simon, I, Koshet, I, Driscoll, D, Nicholls, R, Cedar, H: Allelespecific replication timing of imprinted gene regions. Nature 1993; 364: 459463.Google Scholar