Early Huntington disease prenatal diagnosis by maternal semiquantitative fluorescent-PCR

Affected families with Huntington disease (HD) may require a prenatal diagnosis to consider terminating pregnancy when the fetus is affected. The prenatal diagnosis is performed by analyzing by PCR the number of expansions of the (CAG)n repeat at 10–13 weeks of gestation using DNA from chorion villus sample (CVS). Fetal DNA in maternal plasma and serum offers a possible source of fetal genetic material for noninvasive prenatal diagnosis1 in order to avoid the 2% risk of abortion in CVS. Up to now, because of the low amount of fetal DNA in early pregnancies,2 the noninvasive detection of fetal DNA is mainly performed from the second trimester of gestation to determine fetal sex and RhD status.3 The detection of some paternally inherited disorders has been also reported.4,5⇓ However, using real-time PCR, fetal sex determination was achieved from the 7th week of gestation.6 Although this technology would be very useful to diagnose sex-linked disorders, it …