Two Cases of Klinefelter Syndrome Identified by Quantitative Fluorescence PCR (QF-PCR) Method

Abstract

Chromosomal aneuploidy is a common cause of genetic abnormality in humans and leading cause of pregnancy loss and congenital birth defects. Pregnancies with chromosomal aneuploidies that survive to term include trisomy 13, 18, and 21 as well as sex chromosome anuploidies with an extra X of Y chromosome. Cytogenetic analysis of metaphase chromosome either by G-banding or fluorescent in situ hybridization (FISH) have been the standard methods for identifying aneuploidies and balanced translocation. However 1-2 weeks are required for the completion of the test as the fetal cells require several days of in vitro culture. Quantitative fluorescence PCR (QF-PCR) offers a suitable alternative for the diagnosis of chromosomal aneuploides thereby reducing the need of cell culture. QF-PCR analysis includes amplification of chromosome specific short tandem repeats (STRs) and non-polymorphic markers followed by capillary electrophoresis. The main advantage of QF-PCR is its speed, accuracy, ease of automation and allow large number of samples to be investigated at a time. This study reports the successful identification of two cases of Klinefelter syndrome from DNA extracted from peripheral blood and amniotic fluid.