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PMID: 6885068 Published · ppublish English Journal Article Research Support, Non-U.S. Gov't

Carrier detection and X-inactivation studies in the fragile X syndrome. Cytogenetic studies in 63 obligate and potential carriers of the fragile X.

Human genetics ·Vol. 64 ·No. 3 ·1983-00-00 ·Pages 240-5

Nielsen KB, Tommerup N, Poulsen H, Jacobsen P, Beck B, Mikkelsen M

Abstract

Cytogenetic investigations by three different lymphocyte culture methods in 63 obligate and potential carriers of the fragile X [fra(X)] are reported. A difference was observed between normal and retarded carriers in the manifestation of the fra(X). An inverse relationship between percentage positive cells and age was demonstrated in normal carriers, whereas retarded carriers generally showed higher percentages at all ages. X-inactivation studies in retarded carriers compared with normal carriers showed a tendency towards a skewed inactivation pattern with an excess of early replicating fra(X) in both groups when carriers expressing high percentages of fra(X) positive cells were compared. In normal carriers with low percentage expression the tendency was apparently reversed. The relationship between the replication pattern of the fragile X and the mental status of the individual is more complicated than suggested by previous studies.

MeSH Terms

Adolescent Adult Age Factors Aged Cell Division Cells, Cultured Child Child, Preschool Chromosome Banding Dosage Compensation, Genetic Female Fragile X Syndrome/genetics Gene Expression Regulation Genetic Carrier Screening Humans Lymphocytes/ultrastructure Male Middle Aged Risk Sex Chromosome Aberrations/genetics

Authors & Affiliations

6 authors, click to expand affiliations / ORCID

Nielsen K B

Tommerup N

Poulsen H

Jacobsen P

Beck B

Mikkelsen M

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24 references, click to expand

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Article Info

Journal

Human genetics

Abbr.

Hum Genet

ISSN

0340-6717

DOI

10.1007/BF00279401

Published

1983-00-00

Pages

240-5

Language

English

Region

Germany

NLM ID

7613873

Subset

External Links

PubMed source DOI: 10.1007/BF00279401 View journal details

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Carrier detection and X-inactivation studies in the fragile X syndrome. Cytogenetic studies in 63 obligate and potential carriers of the fragile X.

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