SIMULTANEOUS DETECTION OF CHROMOSOME-X, CHROMOSOME-Y, CHROMOSOME-13, CHROMOSOME-18, AND CHROMOSOME-21 BY FLUORESCENCE IN-SITU HYBRIDIZATIONIN BLASTOMERES OBTAINED FROM PREIMPLANTATION EMBRYOS

Purpose. Simultaneous fluorescence in situ hybridization (FISH) was us ed in a preimplantation generic diagnosis program to determine which e mbryos were normal for chromosomes X, Y, 13, 18, and 21. Methods: Sing le blastomeres, were disrupted and attached to glass slides using acet ic acid and ethanol. Using a ratio mixture of chromosome enumeration D NA probes in combination with locus-specific identifier DNA probes, FI SH was performed for the identification of chromosomes X, Y, 13, 18, a nd 21. Results: Fourteen couples enrolled in IVF produced 134 embryos for biopsy. Blastomeres subjected to five-color FISH revealed that 22% of embryos were normal for chromosomes X, Y, 13, 18, and 21. In addit ion, 52% were abnormal and no results could be detected for 25%. Twelv e couples underwent embryo transfer two couples did not receive embryo s due to lack of any normal embryos, and three couples became pregnant . Conclusions: The simultaneous detection of five-color FISH is a feas ible method to detect aneuploidy in preimplantation embryos from women of advanced maternal age.