Preimplantation genetic diagnosis: a challenge for the XXIst century

The embryo preimplantation genetic diagnosis (PID) was proposed to avoid th e birth of genetically abnormal babies without the recourse to medical abor tion as it may occur with prenatal diagnosis (PND). In fact the number, ava ilability and statute of the potential persons submitted to diagnosis by ei ther PID or PND are not comparable. It is why the medical indications for P ID already begin to overstep particularly serious diseases. However PID wil l be limited to few cases till the supervention of certain new biological p rocedures in addition to molecular genetics. These procedures include: (1) increasing production of mature oocytes; (2) use of numerous genetic tests for each resulting embryo; and (3) cellular cloning of << the best >> avail able embryo. By cryopreserving many copies of this elected embryo one can a ssure the birth of a corresponding child despite the low pregnancy rate fro m each embryo transfer. To prevent such a eugenic future scenario, an inter national specific regulation on PID is a matter of urgency. We propose to l imit DNA identification in ex vivo embryos to only one gene, whereas chromo some aneuploidies should be detected without restriction.