Abstract |
The presence of an isochromosome Xq in Klinefelter syndrome (KS) is an apparently rare condition. In all cases reported so far, patients showed the classic phenotype. We here describe a case of isochromosome Xq [47,X,i(Xq),Y] in a non-mosaic KS patient. The patient exhibited a normal androgenized phenotype, normal testes and normal cognitive abilities. Semen analysis revealed a medium oligozoospermia (5 x 10(6) spermatozoa/ml). After the patient underwent intracytoplasmic sperm injection, he generated two cytogenetically healthy normal females. Fluorescence in situ hybridization analysis showed the presence of a dicentric Xq chromosome that did not show the presence of residual Xp arm up to the 57,820,478 bp position (Xp 1.1) of X chromosome sequence. Preferential inactivation of Xq isochromosome was demonstrated by bromodeoxyuridine replication analysis and transcriptional silencing by DNA methylation at the HUMARA locus. Furthermore, we demonstrated by quantitative RT-PCR an active XIST RNA expression in blood lymphocytes from Klinefelter patients, comparable to that observed in control females and over 30,000-fold greater than in control males. In conclusion, this qRT-PCR approach could be useful for screening of prepuberty males and for diagnosis or exclusion of cryptic Klinefelter mosaics.
|
Authors | M Stabile, T Angelino, F Caiazzo, P Olivieri, N De Marchi, L De Petrocellis, P Orlando |
Journal | Molecular human reproduction
(Mol Hum Reprod)
Vol. 14
Issue 11
Pg. 635-40
(Nov 2008)
ISSN: 1460-2407 [Electronic] England |
PMID | 18854511
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
|
Chemical References |
- RNA, Long Noncoding
- RNA, Untranslated
- XIST non-coding RNA
|
Topics |
- Adult
- Chromosomes, Human, X
(genetics)
- Female
- Fertility
(genetics)
- Gene Expression Regulation
(genetics)
- Humans
- Klinefelter Syndrome
(blood, complications, genetics)
- Male
- Oligospermia
(blood, etiology, genetics)
- RNA, Long Noncoding
- RNA, Untranslated
(blood, genetics)
- Reverse Transcriptase Polymerase Chain Reaction
|