Preimplantation Prenatal Diagnosis within the Framework of Reproductive Medicine and Rep-roductive Genetics

Overview

Integration of reproductive medicine and reproductive genetics provides the possibility to use preimplantationprenatal genetic diagnosis in earliest genetic prevention also in our country as well as to improve it for the coupleswith reproductive problems and their families. The specialized genetic counselling is recommended to all coupleswith their problems. In 60% it provide better health care and in 40% couples it indicates periconceptional andprenatal genetic prevention. This counselling is obligatory for suggested oocyte donors. Cytogenetic examinationwas performed in both partners with reproductive failure. The aberrations of heterochromosomes represent themajority of chromosome anomalies, detected in 4.6% - 5.6% male and female partners. In males, chromosomeanomalies were disclosed only in males with sperm count lower that 20 x 10 6 /ml from 247 examined. The mostfrequent CFTR mutations are screened in all couples. The 19% of delta F 508 carriers was revealed in males with non obstructive azoospermia or oligospermia with sperm count lower than 1 x 10 6 /ml. In men with severereproductive problems the aneuploidy detection by FISH in sperm is recommended in order to disclose the degreeof chromosome aneuploidy. All methods of reproductive medicine and reproductive genetics including prenataldiagnosis are integrated in one center to prepare implementation of preimplantation genetic diagnosis. The successof oocyte aspiration was in 96% of stimulated cycles. The average of 4.16 embryos for transfer, 95.6% of embryotransfer, 24.5% of clinical gravidities and 16.7% of delivered babies per transfer were achieved. ICSI assured 93%transfer rate per successfully stimulated cycle. Successful FISH analysis of blastomers and sperms after 0.075 MKCl hypotonization made possible detection of aneuploidies of chromosomes X, Y, 13, 18 and 21. The nested PCRand quantitative fluorescent PCR were introduced for gene mutations examination and aneuploidy detection insingle cells. Experimental verification of these methods on embryos unsuitable for kryopreservation or embryonaltransfer is obligatory before the clinical implication of preimplantation diagnosis.

Key words:
reproductive medicine, reproductive genetics, preimplantation genetic diagnosis, chromosomeaberrations, azoospermia, oligospermia, CFTR mutations, FISH, sperms, oocytes, blastomeres, quantitativefluorescent PCR, genetic councelling