Del Xq23 in a Mosaic Turner Female: Molecular and Cytogenetic Studies

• Published in: Annales de génétique Vol. 44; no. 4; pp. 171 - 174
• Main Authors: Mesa-Cornejo, Viviana Matilde, García-Cruz, Diana, Monroy-Jaramillo, Nancy, Vásquez, Ana Isabel, Dávalos, Nory Omayra, Galaviz, Carlos, Kofman, Susana
• Format: Journal Article
• Language: English
• Published: Paris Elsevier SAS 01-10-2001; Société d'édition de l'association d'enseignement médical des hôpitaux de Paris
• Subjects: Adult; Biological and medical sciences; Chromosome aberrations; Chromosome Deletion; Female; gonadal dysgenesis; Humans; Karyotyping; Lymphocytes - blood; Lymphocytes - pathology; Medical genetics; Medical sciences; Metaphase - genetics; Microsatellite Repeats; microsatellites; Mosaicism; Polymerase Chain Reaction - methods; Recombination, Genetic; Turner mosaic; Turner Syndrome - genetics; X Chromosome; Xq23 deletion; microsatellites; X-chromosome; Turner mosaic; gonadal dysgenesis; Xq23 deletion; Human; Recombination; Late; Maternal origin; Family study; Partial deletion; Probability; Chromosome; Marker; Inactivation; Probe; Telomere; Case study; Signal; Fluorescence in situ hybridization; Cytogenetics; Female; Replication; Karyotype
• ISSN: 0003-3995
• DOI: 10.1016/S0003-3995(01)01092-9

We report a Turner patient aged 22 years with a 45,X/46,X,del(X)(q23) karyotype. Late replication studies showed preferential inactivation of the deleted X chromosome; FISH studies with a probe for total human telomeres showed hybridisation signal in the telomeres on both the normal and the deleted X chromosomes. Microsatellite analysis in the proposita and her family permitted us to conclude to the maternal origin of the deleted X chromosome, and to detect using the marker DXS1106 (Xq22) a probable meiotic recombination event above the breakage point suggesting that the deletion occurred underneath this point.
The mild Turner stigmata may be explained by the 45,X cell line, and the gonadal dysgenesis probably by a partial deletion of the gonadal dysgenesis region Xq13-q23 (excluding Xq22).