FISH Detects Mosaic Cell Lines in Patients with Turner Syndrome

Many patients with Turner syndrome have phenotypic characteristics at odds with their karyotype, suggesting that they might have a mosaic cell line not detected by . . .

Many patients with Turner syndrome have phenotypic characteristics at odds with their karyotype, suggesting that they might have a mosaic cell line not detected by conventional karyotyping, which studies 20 to 30 cells. These investigators used fluorescence in situ hybridization (FISH), which allows assessment of hundreds of cells for cytogenetic study, to determine the prevalence of mosaicism in women with Turner syndrome. (The American College of Medical Genetics recommends cytogenetic analysis of 30 metaphase cells; such analysis can identify, with a confidence level of 95%, patients with 10% mosaicism.)

Among 53 women with Turner syndrome and a 45,X cell line, karyotyping showed various mosaic complements in 34. The remaining 19 women ha…

Reviewing Author

Sandra Ann Carson, MD