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ABSTRACT
The development of in vitro fertilization techniques (IVF) and the possibility to obtain gametic and embryonic cells useable for the genetic diseases diagnosis determined a widening of the prenatal diagnosis application perspectives, making possible the transfer of the diagnosis age from the ‘post- implantation’ phase to the ‘pre-implantation’ phase.
The pre-implantation genetic diagnosis (PGD) represents a new method, complementary to the pre-natal diagnosis techniques, which allows to identify the presence of hereditary diseases or chromosomal alterations in embryos obtained in vitro from couples with an elevated reproductive risk from the very first development phases and before their transfer in the uterus. Before to have recourse to assisted reproduction technique it is necessary to effect a careful personal and familiar case history, including any genetic analysis in order to mark chromosomal and/or genetic anomalies of the couple who wants to embark in this journey.
The Thesis consists in the seek to develop a technique on the cells, starting from peripheral blood lymphocytes and / or amniocytes in order to acquire the necessary dexterity to apply it on the single blastomeres of embryos before their transfer, avoiding couples who undergo this technique to have recourse to the therapeutic abortion, which is often debilitating from a psychological point of view and not always accepted from the ethic/moral point of view.
The PGD mainly relies on two techniques:
1. The use of the technique of molecular cytogenetics for the estimate of chromosomal anomalies, the fluorescent in situ hybridization (FISH);
2. The use of the molecular genetic techniques for the analysis of the genes responsible for monogenic diseases (PCR).
The FISH technique allows to analyse the fetal chromosomes’s numerical and
structural order, while the PCR technique allows to diagnose some numerical
chromosomal anomalies (13, 18, 21, X, Y) and it is also applied to determine
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