Turner syndrome seen sooner with new test

Turner syndrome (TS) is a relatively common genetic condition in females in which some or all of the X chromosome is deleted, causing stunted growth and heart and kidney problems. TS can be diagnosed with a karyotype (above), but these are labor intensive and impractical as a routine test, so the disorder often goes undetected until girls reach 10 years of age.

In the March issue of the Journal of Clinical Endocrinology & Metabolism, Scott A. Rivkees, M.D., professor of pediatrics, and colleagues describe a genetic test for TS that is quicker, less expensive, and more amenable to large-scale use than karyotyping. The new screen, which analyzes variations in DNA at 18 sites on the X chromosome, diagnosed TS with almost perfect accuracy in 132 females without TS and 74 females known to have TS based on prior karyotype analyses.

The team notes that very short girls could be tested early for TS, enabling intervention with growth hormone and treatments for organ defects. “If broadly used in the clinical setting at young ages, this test can prevent the delayed recognition of TS,” Rivkees says.