Overview
What Is QSTR Trisomy Analysis?
QSTR (Quantitative Short Tandem Repeat) analysis is a molecular method used to rapidly detect the most common chromosomal trisomies from prenatal samples obtained by amniocentesis or chorionic villus sampling (CVS) or buccal swabs . CARIGEN uses quantitative fluorescence PCR (QF-PCR) to assess markers on chromosomes 13, 18, 21, X and Y — detecting the common trisomies and sex chromosome aneuploidies such as Turner syndrome (monosomy X) and Klinefelter syndrome (47,XXY) in a single test. It is used to confirm positive first-trimester or NIPT screens.
- Trisomy 21 (Down Syndrome)
- Trisomy 18 (Edwards Syndrome)
- Trisomy 13 (Patau Syndrome)
- Turner Syndrome (Monosomy X)
- Klinefelter Syndrome (47,XXY)
Sample Requirements
QSTR analysis is performed on amniotic fluid (amniocentesis) or chorionic villus samples (CVS) or buccal swabs — invasive diagnostic procedures performed by a specialist obstetrician. Results in 3–5 business days, compared with up to 14 days for standard cytogenetics. QSTR Plus Screen: J$45,000.
Validated for Diagnostic Use
Unlike NIPT screening, QSTR analysis is performed on fetal cells and is fully validated for in vitro diagnostic use on chorionic villus and amniotic fluid samples, with greater than 99% concordance with standard karyotyping. It can be used as a preliminary test before karyotyping or for final analysis.