[Prerequisites for preimplantation genetic diagnosis (PGD in carriers of mutations responsible for hereditary cancers].

BACKGROUNDS

Carriers of hereditary mutations in cancer susceptibility genes represent a limited but high-risk population characterized by a high probability of cancer development, frequently with its manifestation in early age and with a 50% chance of pathogenic allele inheritance by offspring. In case of monogenic disorders, preimplantation genetic diagnosis (PGD) could be used for characterization of the DNA region affected by pathogenic mutation in the early stages of an embryo created by in vitro fertilization (IVF). Therefore, the transfer of unaffected embryos could be performed based on the results of PGD genotyping, enabling the development of offspring not carrying the pathogenic alteration.

AIM

Here we present the consensus of the collaborative group of the Society for Medical Genetics, the Czech Society for Oncology and other professionals for use of PGD in the Czech Republic for carriers of mutations in cancer susceptibility genes. We address the conditions, prerequisites, and limits of practical application of this method. We also point out specific issues of ovarian hyperstimulation in carriers of mutations in BRCA1, BRCA2, and p53, anticipating the increased risk of hormonally dependent breast and ovarian cancers development.

CONCLUSIONS

We assume that a narrow but non-negligible subgroup of cancer susceptibility gene mutation carriers may benefit from PGD.They are mainly individuals deciding to undergo IVF and PGD recruited from mutation carriers with extreme concerns about transmitting the mutation to their children. The PGD in these individuals should be managed by a closely cooperating multidisciplinary team of professionals responsible for indication of PGD, giving complete information regarding the IVF and PGD procedures including their limits, evaluating individual risks and performing instrumental and laboratory procedures with respect to up-to-date good laboratory and clinical practice.