A normal birth following preimplantation genetic diagnosis by FISH determination in the carriers of der(15)t(Y;15)(Yq12;15p11) translocations: two case reports.

PURPOSE: To investigate the clinical application of fluorescence in situ hybridization (FISH) for assessing chromosome disorders of embryos in preimplantation diagnosis of carriers with der(15)t(Y;15)(q12;p11) translocations.

METHODS

Multicolor FISH was performed using directly-labelled DNA probes, chromosome X with one (DXZ1, Xp11.1-q11.1), but Y with two (DYZ3, Yp11.1-q11.1 and DYZ1, Yq12). Normal embryos were transferred on day 6 at blastocyst stage.

RESULTS

Couple A: Three of 6 biopsied embryos were normal. Two normal blastocysts were transferred, but no pregnancy was achieved. Couple B: Three of 6 biopsied embryos were normal. Two normal blastocysts were transferred. A normal male infant weighing 3,230 g was born by cesarean section on the 39th week of gestation. All of the remaining nonreplaced embryos showed mosaic or der(15).

CONCLUSION

Embryos from carries of der(15)t(Y;15)(q12;p11) translocation showed a high frequency of chromosome abnormalities. PGD is a valuable screen tool for those couples to treat their infertility and break the transmission of der(15) chromosome for their offspring.