ANALYSIS OF FETAL NUCLEIC ACIDS IN MATERNAL PLASMA FOR NONINVASIVE PRENATAL DIAGNOSIS OF GENETIC DISEASES AND MONITORING OF PREGNANCY COMPLICATIONS

The presence of fetal DNA and RNA in maternal plasma has been recently demonstrated, this representing a source of fetal genetic material obtained noninvasively. Our main goals will be to set up advanced methodologies for noninvasive prenatal diagnosis of paternally inherited mutations in genetic disorders and to evaluate whether fetal RNA in maternal plasma may represent a useful marker for gene expression profiling of the fetus. Furthermore, we still need to increase our quantitative data about fetal DNA release in pregnancy pathological conditions obtained in the previous projects in order to definitively assess the clinical usefulness of fetal DNA as a predictive or diagnostic marker in pathological pregnancies. For mutation detection, we will evaluate and compare two advanced methodologies: a microchip approach and pyrosequencing. We already proved that both technologies are sufficiently sensitive to be applied to the identification of a paternally inherited fetal allele in maternal plasma. As a model system, tests to detect mutations causing beta-thalassemia will be carried out with both approaches and will be applied to the analysis of maternal plasma in couples at risk for beta-thalassemia. This will be the basis for developing additional assays to identify mutations or polymorphisms in other genetic disorders. We will also explore the feasibility of fetal RNA analysis in maternal plasma in order to evaluate whether this may be a better early predictive marker of the development of feto-placental pathologies than fetal DNA. To this aim we will continue to perform quantitative analysis of both DNA and RNA in maternal plasma collected from pregnancies affected or at risk of developing preclampsia and/or intra uterine growth restriction (IUGR).